# Vampire vs Me 262



## bigZ (Jan 19, 2008)

How do you think the Vampire would perform against the 262?


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## delcyros (Jan 20, 2008)

bigZ said:


> How do you think the Vampire would perform against the 262?



Which Vampire? Which Me-262? If contemporary, than the Vampire MK I is more or less equal to the Me-262A in almost every respect, with the exception of better maneuverability, worser gunsight, worser stall speed behavior and worser high speed behavior. The post war Vampire F IV has an advantage of acceleration and climb, but here, nobody knows what the Me-262 would receive as advantages as her development ended (The czech buildt Avia S92 was continuing the production on the base of captured tooling devices).

An Oberammergau document dating from feb. 1945 shows different stages of "improvements" of the serial production Me-262A. The most basic improvement is given below in comparison to the calibrated, average speed test of 120+ serial Me-262 performed in january 1945. It does show only slight improvements of the canopy, the controlls and surface treatment, all to be implemented in serial production along with the Jumo-004D4 in april 1945 (the graph is for Jumo-004B3, about 3.5% less avaiable thrust). There is some evidence that a few of these improved Me-262A reached an advanced stage in assembling to receive Werknummern. None of those came into combat. The graph is based on the performances of the V-9 high speed prototype, modified to these improvements in 1944.


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## bigZ (Jan 20, 2008)

Thanks delcyros. I thought the maneuverability of the Vampire would be better. But surely the Vampire had a Gyro gunsight giving it the edge talking contempory.


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## Soren (Jan 20, 2008)

Maneuverability would only be better at low speeds, at high speeds the Me-262 has the edge.


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## delcyros (Jan 20, 2008)

There is nothing wrong with the maneuverability of the Vampire. It outrolls the -262 at most speeds, was cleared for full acrobatics and turned very well. 

Charackteristics of maneuverability:
Low wingload, mass concentrated, finely balanced ailerons. Light Stick (very sensitive), good roll charackteristics through the entire speed regime.
Elevator very sensitive, pulling to hard will give no stall warnings. Pilots have to be careful, not to enter unintended spins, esspeccially at lower speeds.
Rudder not very sensitive, demanded coarse movement to be of much consequence.
The aeroplane was agile within the 600-800km/h speed range at low level. At lower speeds, however, steep turns required coarse use of rudder to maintain height, and it was uncomfortably simple to stall in relatively shallow turns.

Stall charackteristics:
The stall was likely to be accompanied by quite sharp wing-drop, but a surprising amount of aileron control existed right down to the stall, albeit with marked control buffet. One was advised to recover quickly while use of the most effective elevator could be maintained. Though by no means dangerous, the spin could be embarrassing owing to blanking of the diminutive rudders and the necessity to use coarse elevator control resulted in the aircraft pointing at terra firma for an uncomfortable length of time while speed built up!

Engine handling:
Pilots experienced in pistonengine handling had to learn to anticipate speed demands earlier as the power response from the Goblin was considerably slower, and any rapid throttle movement might cause engine surge, flame out or, at worst, a burst compressor (this is very typical for early generation jet engines, altough this belongs to planes with Goblin II not H1A. I suppose the charackteristic for the earlier engine is not better). In this regard, there is little difference between Jumo-004 and Goblin.

High speed handling:
At the upper end of the speed range, the Vampire behaved in singular fashion with the onset of compressibility, and from M=0.71 up to 0.76 the aircraft displayed increasing porpoising and wing buffet until at M0.79 the aircraft would suddenly "break" up or down with the likelihood of a wing drop, giving the sensation of an "incipient" flick roll.

The Vampire MK IV was not equipped with a gyro gunsight. It featured a normal reflector gunsight type.


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## Soren (Jan 20, 2008)

Delcyros the Vampire wasn't anywhere near as forgiving as the Me-262, and at high speed it was at a disadvantage to the Me-262. 

You can read about the aerodynamics of the a/c at NASA's website:
ch11-2


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## delcyros (Jan 21, 2008)

The NASA page doesn´t tell You anything about the Vampires maneuverability. The Me-262 certainly cannot outmanouvre a Vampire for most of the speed range, except the extreme slow and extreme fast ranges.


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## bigZ (Jan 21, 2008)

Appreciate the incite guys. Was their a reason for not fitting a Gyro Gunsight for the Vampire?


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## delcyros (Jan 21, 2008)

I don´t know for sure but I suppose it has something to do with avaiability and priorities perhaps? In the net, the early Vampire appears to be consistently noted for having reflector type gunsights:



> The aircraft was armed with four Hispano Mark V 20 millimeter cannon in the bottom of the nose, with a maximum of 150 rounds per gun. They were aimed by a reflector-type gunsight. There was a gun camera in the nose.



[1.0] Vampire Variants

MK 4E gyro gunsights have been refitted by the late 40´s as standart equipment.


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## Soren (Jan 22, 2008)

delcyros said:


> The NASA page doesn´t tell You anything about the Vampires maneuverability. The Me-262 certainly cannot outmanouvre a Vampire for most of the speed range, except the extreme slow and extreme fast ranges.




It can out-turn the Vampire at all speeds, but not out-roll it. And roll rate is an important aspect, esp. as speed increases and turn performance is restricted by the airframe pilot. Roll rate becomes very decisive here.


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## delcyros (Jan 25, 2008)

Have you ever flown a Vampire? Or for that matter a Me-262? I cannot say to have done either but You claim it will outturn them without having any proof for this claim. It´s pure speculation.
Have you turn charts on your hand to proof Your claim? I doubt so.
And if you come to an physical aproach,


> "to do this, you will need engineering drawings, which will have to be digitized, a good meshing program, unsteady and steady CFD programs -- I suggest VSAERO, FLIDYN, and USAERO from Analytical Methods, Inc -- and a structures program, such as ANSYS(I'm basically a fluids guy image). After some training (I suggest at least a BS in aerodynamics, in addition to specialized training in the different programs), a couple of cycles, to make sure that you're getting decent matches with reliable flight test data, you can write a paper and submit to the AIAA Journal of Aircraft or one of the equivalent publications, respond to the referees' comments, and have your name blazoned in ink. It will, of course, make absolutely no difference in anybody's opinion."


 -emc 

Sustained turn performance is in relationship of power avaiable and power required for preventing a stall. The Me-262´s wing does provide less lift and has less powerload than the Vampire´s. It cannot outturn the Vampire over the whole speed regime on a sustained turn base.


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## fly boy (Jan 25, 2008)

i would go for 262 even though you have to slowly thottle up or down


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## B-17engineer (Jan 25, 2008)

i say 262


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## Soren (Jan 25, 2008)

Delcyros,

The Me-262's wing doesn't provide less lift, it infact provides approx. 25% more lift pr. area than the Vampire's wing. So unless you're suggesting that the Vampire has a 25% larger wing area your argument just doesn't hold water.

And as to power-loading, well again the Me-262 holds a clear advantage with 17.6 kN vs the Vampire's 9.3 kN. (Hence the Me-262 much superior performance)

So like I said the Me-262 easily out-turns the Vampire through the entire speed regime.


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## delcyros (Jan 25, 2008)

> The Me-262's wing doesn't provide less lift, it infact provides approx. 25% more lift pr. area than the Vampire's wing. So unless you're suggesting that the Vampire has a 25% larger wing area your argument just doesn't hold water.


No,I suggest to look into the Vampire´s airfoil and it´s properties. It features EC1240/0640 airfoils, with a 14% thickness at the root and 9% at the wingtip. Corrected for the reynolds number this yields a *good 18% better Cl-max* than the Me-262´s semi-symetrical 12% at the wingroots and 6% the wingtips. And this Cl-max is reached at more comfortable angle´s of attack, too. Wingload for the Vampire is 175 Kg/m^2 (corrected for airfoil and max CL: 136.7Kg/m^2). Me-262 wingload is 294,9Kg/m^2 (corrected for airfoil and max CL: 268.1 Kg/m^2 and 214,4Kg/m^2 with full span LE-slats deployed, respectively). So basically, yes, the Vampires wing does provide more lift effectively.



> And as to power-loading, well again the Me-262 holds a clear advantage with 17.6 kN vs the Vampire's 9.3 kN. (Hence the Me-262 much superior performance)


Uhh, wait a minute. Two Jumo-004B4 will yield 3.923lbs/1.780Kp thrust, that´s not 17.6KN! The Vampire I has a H-1A delivering 2.770 lbs of thrust (=~2.600lbs/1.180Kp if we factor in air intake / exhoust losses). The problem is that the Vampire I weights 3.899Kg normal while the Me-262A weights 6000Kg normal (both without external loads and hardpoints/droptanks). The resulting thrust/weight ratios are 0.303 for the Vampire and 0.297 for the Me-262, not much to tell between both. If anyone, than the Me-262 does NOT hold the advantage in powerload.

It is not necessary to overexaggerate the Me-262´s abilities. It has advantages over the Vampire but turning performance most likely is not one of them.


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## Soren (Jan 26, 2008)

For crying out loud Delcyros! Are you just making up stuff as you go along ? 

The Jumo 004B's max output is 8.8kN (1,980 lbft), and the Me-262 has two of them !

The max output of the Vampire FB.1's Goblin 1 is 9.3 kN (2,100 lbft)!

You can see the different thrust figures available to the different De Havilland a/c here:
de Havilland data

The Me-262's empty weight is 3,800 kg, the Vampire's empty weight is 3,300 kg, so thats a power-loading of 215 kg/kN vs 314 kg/kN respectively. It's no wonder that the Me-262 is considerably faster at 870 km/h, and climbs faster at 3,900 ft/min, despite being a larger a/c. (The Vampire FB.5 with a 13.8 kN engine climbs at 4,500 ft/min and isn't even as fast at 866 km/h)

And as to the airfoils, again you seem to just be making up stuff and then base your wild claims on it.

The official airfoil thickness ratio of the Me-262 is 11% at the root and 9% at the tips. The airfoil design used was the NACA 00011-0.825-35 NACA 00009-1.1-40.

The Vampire's airfoil thickness ratio is 14% at the root and 9% at the tip, not hat different from the Me-262. The airfoil type used was the EC1240/0640 EC1240/0640.

And as to your CLmax figures, well they are based solely on thickness ratio, which is ridiculous cause you can't even begin to figure out CLmax by just using thickness ratios for crying out loud! First of all there's no std. increase in Clmax with an increase in thickness ratio, infact Clmax may drop with an increase in thickness ratio depending on the airfoil type, so you can forget that those ridiculous Clmax figures you posted !

For example a NACA 23000 series airfoil (Known for its high CLmax figures) of 9 - 16% thickness ratio has a CLmax of 1.58 to 1.64 ! That's a lot more than usual. But as the thickness ratio increases to 18% the CLmax actually starts to drop. 

So like I said the Me-262 holds a lift advantage of ~25% pr. surface area, giving it a lower lift-loading, and it also holds a good advantage in power to weight ratio.

(3,800 kg / 21.7)*0.75 = 131.33 kg/m^2
(3,300 kg / 24.3) = 135.8 kg/m^2


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## Glider (Jan 26, 2008)

I notice from the De Haviland web site that the F1 was fitted with the 2,100lb engine and later the 3,100lb engine. The extra 1,000lb would make all the difference to the performance.
What isn't clear is when the switch was made.


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## red admiral (Jan 26, 2008)

The H.1 was initially tested at 2300lbf which was then increased to 2700lbf in the Goblin I and 3000lbf in the Goblin II and then 3100lbf in the Goblin III.

I have no idea where Soren's stats on the Vampire come from, and the use of empty weights more or less completely nullifies the discussion. Using empty weight gives the Me 262 a massive advantage in as it completely overlooks the much higher fuel consumption of the 2x004s compared to the single Goblin. Combat weight (mid between empty-max) shoudl be used.

The Me 262 climbs much slower at 3900ft/m against 4500ft/min and the speed differential is an entire 4mph in favour of the Me 262. Vampire FB.5 had slightly more thrust but put on weight through extra equipment postwar.


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## Soren (Jan 26, 2008)

red admiral,

Try actually reading my post before jumping to conclusions. I linked my source on the Goblin engines. 

The Vampire FB.5 is the one which climbs at 4,500 ft/min and has a top speed of 866 km/h, NOT the Vampire Mk.I which is the only version which saw service in 45. Do you even know when the different versions saw service??

Also there's nothing wrong with using empty weights, esp. since it's only natural that a more powerful a/c consumes more fuel. Also the use of the Jumo 004D would've not only decreased fuel consumption but also increased power to 10.3 kN.


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## Glider (Jan 27, 2008)

I have found out that the 3,100lb thrust version of the Goblin was fitted to the 41st Vampire mk1 onwards. 
The Mk1 with the larger engine would I have thought been a pretty hot plane to fly without the extra weight added to the Mk3 let alone the Mk 5.

Re the different engine powers, All I can say is that the incremental jumps in power are likely to have happened during development, but the chances of those differing versions were fitted into production aircraft over such a short time period is small.


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## delcyros (Jan 28, 2008)

Soren said:


> The Jumo 004B's max output is 8.8kN (1,980 lbft), and the Me-262 has two of them !
> The max output of the Vampire FB.1's Goblin 1 is 9.3 kN (2,100 lbft)!



Actually, the Jumo-004B3/4 were the only models rated to 890 Kp thrust, the B-2 was limited to 840 Kp and the B-0/B-1 rated to 820 Kp, respectively. By 1945, the vast majority of engines were Jumo-004B3/4. Only the Spider-Cap prototype hat 2.100 lbs rated H-1A´s, The Vampire F-I (there was no FB-I) was serially equipped with Goblin-I rated to 2.700 to 2.770 lbs, while using a more sophisticated mark rated to 3.100 lbs installed from the 41st serial plane onwards.



> The Me-262's empty weight is 3,800 kg, the Vampire's empty weight is 3,300 kg, so thats a power-loading of 215 kg/kN vs 314 kg/kN respectively. It's no wonder that the Me-262 is considerably faster at 870 km/h, and climbs faster at 3,900 ft/min, despite being a larger a/c. (The Vampire FB.5 with a 13.8 kN engine climbs at 4,500 ft/min and isn't even as fast at 866 km/h)


You are comparing apples with oranges. The FB-5 is a heavier fighter-bomber variant and in this condition (no fuel, no ammo, no loads) neither plane will be able to take off. Comparisons are usually placed at normal (full combat load), occassionally at overloaded fighter configuration in order to reflect operational conditions, both of which place the Me-262 at a slight disadvantage.



> And as to the airfoils, again you seem to just be making up stuff and then base your wild claims on it.
> 
> The official airfoil thickness ratio of the Me-262 is 11% at the root and 9% at the tips. The airfoil design used was the NACA 00011-0.825-35 NACA 00009-1.1-40.
> 
> The Vampire's airfoil thickness ratio is 14% at the root and 9% at the tip, not hat different from the Me-262. The airfoil type used was the EC1240/0640 EC1240/0640.


No claims, just proofs. Unlike You, I have access to the profiles in question. And your data don´t contradict mine (NACA 00011 is semi-symetrical).



> And as to your CLmax figures, well they are based solely on thickness ratio, which is ridiculous cause you can't even begin to figure out CLmax by just using thickness ratios for crying out loud! First of all there's no std. increase in Clmax with an increase in thickness ratio, infact Clmax may drop with an increase in thickness ratio depending on the airfoil type, so you can forget that those ridiculous Clmax figures you posted !


No. My Cl-max figures do come from drag/lift profiles, provided by profile software. Thickness ratio is not the decisive aspect in airfoil performances. If you have access to ordinates of the profiles (to be obtained in the net) and Mark Drelas or other software (profile 2.0 is excellent) You will find my values for Cl-max substantiated. Don´t forget to use the profile for the correct reynold-numbers! Each airfoil has different profiles for different RE-numbers.



> For example a NACA 23000 series airfoil (Known for its high CLmax figures) of 9 - 16% thickness ratio has a CLmax of 1.58 to 1.64 ! That's a lot more than usual. But as the thickness ratio increases to 18% the CLmax actually starts to drop.


That´s pretty irrelevant as neither the Me-262 nor the Vampire had this airfoil.



> So like I said the Me-262 holds a lift advantage of ~25% pr. surface area, giving it a lower lift-loading, and it also holds a good advantage in power to weight ratio. (3,800 kg / 21.7)*0.75 = 131.33 kg/m^2
> (3,300 kg / 24.3) = 135.8 kg/m^2


 Disagreed. You are free to verify this on Your own, my friend. Assuming that both planes have the SAME AIRFOIL is a substantial and in this case basic error.



> The H.1 was initially tested at 2300lbf which was then increased to 2700lbf in the Goblin I and 3000lbf in the Goblin II and then 3100lbf in the Goblin III.


Yes. Agreed 100%.



> The Vampire FB.5 is the one which climbs at 4,500 ft/min and has a top speed of 866 km/h, NOT the Vampire Mk.I which is the only version which saw service in 45. Do you even know when the different versions saw service??


There is only a slight difference in speed and performance between Vampire FIII and Vampire FB-V. The Vampire F-I using Goblin-I (2700lbs) is slightly lower rated but in no ways inferior as pointed out above at any condition other than "almost empty".



> Also there's nothing wrong with using empty weights, esp. since it's only natural that a more powerful a/c consumes more fuel. Also the use of the Jumo 004D would've not only decreased fuel consumption but also increased power to 10.3 kN.


 Anthony Kay rates the Jumo-004D4 (of which none ever equipped Me-262A´s to see combat) with 930Kp thrust (9.1KN). The Jumo-004E without reheat was rated to 1000 Kp (9.8KN) thrust, but this engine, too was about to be produced.


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## DerAdlerIstGelandet (Jan 28, 2008)

Soren instead of telling people they are full of ****, post some sources to back up your facts. Then there is no arguement...


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## Glider (Jan 28, 2008)

I have found some stats on the Vampire F1 which people may want to compare to the 262.
de Havilland D.H.100 Vampire - History, Specifications and Pictures - World Military Aircraft

Its seems to be more than a match in most areas.


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## Soren (Jan 28, 2008)

DerAdlerIstGelandet said:


> Soren instead of telling people they are full of ****, post some sources to back up your facts. Then there is no arguement...



I never said he was full of ****, I was questioning his info as assumptions as he seems to be posting about something which he has limited knowledge on.

Also I did post sources Adler, you just overlooked them. On the other hand Delcyros has posted no sources for his info on the Me262 or Vampire.

The Jumo 004B's out-put is 8.8kN, that's fact, Delcyros just wants to slither around this.

Delcyros,

I'd like to see the results from the drag/lift profile software in the form of screenshots please. I'm esp. interested since Foilsim VSAERO is showing very different results from yours!

Also the root thickness ratio of the Me262's wing is 11% and the tip 9%.

Look here for more information on airfoils:
The Incomplete Guide to Airfoil Usage

This isn't a battle of points, you don't loose face being wrong.


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## DerAdlerIstGelandet (Jan 29, 2008)

Soren said:


> I never said he was full of ****, I was questioning his info as assumptions as he seems to be posting about something which he has limited knowledge on.



Soren it is a term used here in the United States. It does not litterally mean you said he was full of ****.


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## Soren (Jan 29, 2008)

I know, but it came across abit harsh Adler, that's all. (I do the same frequently, it's a bad habbit, I'm a very straight forward person) Things easily get interpreted incorrectly on forum boards. You cleared up what you meant, all is good.


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## delcyros (Feb 12, 2008)

I am pretty sure, I could file screenshot the whole day long and wouldn´t change Your mind, Soren. 
The design Clmax of Vampire and Me-262 aren´t the same. 
Please check the NACA report 647, avaiable online for the Cl-max of the NACA 0009 and 0012 airfoils for the following condition (full scale AR: 6.0 models tested at standart atmossheres for 100 mp/h).

The Vampire´s EC 1240/0640 airfoil is investigated in R. M No° 2678
(11084, 11191) A.R.C. Technical Report and compared with the NACA 0012. Bottom line is that the NACA 0012 (AR=6)has a CLmax of 1.40 and Reynoldsnumber of 5.0 mill. at Mach=0.1 compared to Clmax =1.26 at R= 5.0 mill. and AR=6 for the NACA 0009. The Cl-max figure of all airfoils drops while engaging higher Mach fractions until about Mach=0.4 where above mentioned report starts to compare the NACA 0012 (remember, it is better than the NACA 0009 in Cl-max by 11.1%) with different other airfoils. You can deduct the logic from this approach: The NACA 0009 has a lower Cl-max than the NACA 0012, which itselfe finds to be little different from the EC 1240/640.

Could one of the moderators resize the images, please? Thanks in advance.


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## Soren (Feb 12, 2008)

Just post the screenshots Delcyros.

Just posting the CLmax figures for the NACA 0009 - 18 series airfoils solves nothing.


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## Seawitch (Feb 12, 2008)

Only a very few 262's out gunned the Vampire


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## delcyros (Feb 12, 2008)

I will submit screenshots of the airfoils and their respective RE-functions as soon as I receive a permission to do so. Some of the software involved requires this.
However, You can see easily that the NACA 0009 does not provide as much lift as a NACA0012 or the Vampire´s EC1240/0640 under identic conditions from the charts above. It is approx. 11.1% short of this in between Mach= 0.1 and Mach = 0.4. Of course, both planes do have different conditions, actually. The aspect ratio is different as is the planform and the reynolds number or the smallest chordlength (which in our cases define the max. Cl due to lift distribution over span by absence of geometric wing twists). To adress these aspects, I used 3d models of the wings in question in order to derive the correct RE-numbers for each section. The models are generated with rds-student (see isometric viewings below, not identic in scale!). 
The critical max. permissable reynolds number for the Vampire wing is 42% higher than for the Me-262 (the shortest airfoil sections at the tips respectively), translating into the aforementioned netto advances of the Vampire. These do define the max. permissable (= flyable) Cl-max. The higher Cl-max of the wingroot sections is only of theoretical interest, it´s use would not be possible for any controlled flightregime (that´s why You have LE-slats usually at the outer wings or a geometric twist to offset the drop in lift distribution towards the wingtips) as it provokes a wingtip stall.
One of the key results from the above mentioned RAF paper is that Cl-max figures of otherwise identic wings ARE NOT BEHAVING like solids. THEY CHANGE with REYNOLDS NUMBERS, MACH FRACTIONS and ASPECT RATIO. While a Cl-max of ~1.25 is possible at Mach 0.1 for a given wing with NACA 0009, the Cl-max at Mach 0.4 is below 0.8 for the same wing! A plane which enjois a lower stall speed benefits from higher possible Cl-figures. Fortunately for us, the Me-262´s stall speed is 175 Km/h (109 mp/h) while the Vampire´s is reported to be 109 mp/h, too. The advantages of the very thin Me-262 wing are coming handy at higher Mach fractions than Mach =0.5 and are substantial at Mach= 0.7. So define maneuvering speed in the first place!


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## Soren (Feb 12, 2008)

Delcyros,

The Me-262's wing has a 11% thickness ratio at the root and 9% at the tip. 

You have shown no CLmax info about the Vampires airfoil yet.


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## delcyros (Feb 12, 2008)

I have already included Your wingroot / wingtip figures.

The Vampire´s wing is also included. See above. For those who understand to read the graph, which is indeed complicated to read, the Vampire´s EC 1240 /0640 appears to have a Cl-max of about 0.75 at Mach= 0.4 are given above in the RAF paper, which concluded them to be little indifferent from the NACA 0012, which in turn is found to be better than the NACA 0009. Note that very low Reynolds numbers have been used for this! It is not before Mach = 0.5 that the graphs for NACA0009 and 0012 close again (another NACA technical report which I have filed down here somewhere) and at Mach = 0.7 the NACA 0009 is superior to the NACA 0012, which has a Cl-max of 0.6 at Mach = 0.7, compared to Cl-max ? 0.8 for the Vampires EC 1240/0640 at Mach = 0.7, which is about the same ballpark of the NACA 0009 for this Mach fraction. The Me-262 wing offers less drag and correspondingly less lift, too.


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## Soren (Feb 13, 2008)

Delcyros,

The chart is easy to read, you just later added report on the EC1240 without me noticing it, and from it you can also see that the NACA 0012 EC1240 have VERY similar CL figures at the different Reynolds numbers.

Also keep in mind that these tests were done with a wing of different planform and with a considerably lower AR, and as we all know CLmax increases with increased AR. The AR of ME-262's wing is 7.23.


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## drgondog (Feb 13, 2008)

Soren said:


> Delcyros,
> 
> The chart is easy to read, you just later added report on the EC1240 without me noticing it, and from it you can also see that the NACA 0012 EC1240 have VERY similar CL figures at the different Reynolds numbers.
> 
> Also keep in mind that these tests were done with a wing of different planform and with a considerably lower AR, and as we all know CLmax increases with increased AR. The AR of ME-262's wing is 7.23.



Induced drag decreases with AR increases all things equal on the airfoil. 

Soren, I think CLmax on these charts usually refer to the two dimensional airfoil (only) for the reason that AR is another (separate) design variable for airfoil data as presented. Maybe I misread what was presented? I didn't see the AR reference in the charts.


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## Evil_Merlin (Feb 13, 2008)

Wow... you know all this bickering back and forth.

the Me-262 had a huge advantage over the Vamp. Experienced pilots who knew how to fly it.

End of story.


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## drgondog (Feb 13, 2008)

Evil_Merlin said:


> Wow... you know all this bickering back and forth.
> 
> the Me-262 had a huge advantage over the Vamp. Experienced pilots who knew how to fly it.
> 
> End of story.



The two engaging in the debate above are bringing facts and opinions sometimes on facts to the table. 

What did you just bring?


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## DerAdlerIstGelandet (Feb 13, 2008)

drgondog said:


> The two engaging in the debate above are bringing facts and opinions sometimes on facts to the table.
> 
> What did you just bring?



A wise man has spoken...


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## Evil_Merlin (Feb 13, 2008)

drgondog said:


> The two engaging in the debate above are bringing facts and opinions sometimes on facts to the table.
> 
> What did you just bring?





So are you honestly saying that the experience that the Me-262 pilots had flying the tempermental machine isn't an advantage?

PS: it also means I'm not stupid enough to get involved in a conversation that involves nearly as much opinion as it does factual data.


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## drgondog (Feb 13, 2008)

Evil_Merlin said:


> So are you honestly saying that the experience that the Me-262 pilots had flying the tempermental machine isn't an advantage?
> 
> PS: it also means I'm not stupid enough to get involved in a conversation that involves nearly as much opinion as it does factual data.



EM - I don't assume you are stupid or ill informed. Just curious what your fact base was to determine that the advantage of a 262 was so great as to arrive at your conclusion?


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## drgondog (Feb 13, 2008)

Evil_Merlin said:


> So are you honestly saying that the experience that the Me-262 pilots had flying the tempermental machine isn't an advantage?
> 
> PS: it also means I'm not stupid enough to get involved in a conversation that involves nearly as much opinion as it does factual data.




EM - The only point I might have been making to you is that you did exactly that (involved in conversation that involves as much opinion as data)?

Further, if you meant advantage that experienced 262 pilots had over 262 pilots that had no experience in the 262, then yes - it is reasonable to make that assumption or express that opinion. But pilot skill prior to Me 262 time a huge factor.

Ditto - advantage of experienced Vampire pilots probably better than Vampire pilots that no experience in the Vampire, then same as above. 

So, what is your thesis? That experienced 262 pilots had an advantage over inexperienced Vampire pilots? Or that experienced Me 262 pilots had an advantage over experienced Vampire pilots? Interesting but where are your facts? And how do you factor in prior experience and flight time?

Moving more into subjective opinion - where the answer could be 'it depends' on;

the quality of the time before transitioning into either a/c, the amount of time each had in the a/c (325 'better than 293'?? 5000 better than 3600?), and the quality of the pilots, and the tactical situation (fuel status, who sees whom first, altitude, airspeed in the engagement, etc)

A lot of these dialogues bring opinion, fact based opinion and simple 'I like it" statements - don't confuse me with facts!

So, help us out here. how did you arrive at "End of Story" for your conclusions?


----------



## Soren (Feb 13, 2008)

drgondog said:


> Induced drag decreases with AR increases all things equal on the airfoil.



Yes induced drag is decreased and CLmax in increased, increasing the L/D ratio, that is the effect an increase in AR has.



> Soren, I think CLmax on these charts usually refer to the two dimensional airfoil (only) for the reason that AR is another (separate) design variable for airfoil data as presented. Maybe I misread what was presented? I didn't see the AR reference in the charts.



The tests refer to wings with an AR of 6.


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## Soren (Feb 14, 2008)

With similar CLmax figures let me demonstrate just how important wing AR is;

L/D ratio = Cl / Cd

Cd = Cd0 + Cdi

Cd0 = {Negligable as it always lies in the 0.02 -0.025 area}

Cdi = (Cl^2)/(pi*AR*e)

So for the comparison we assume a Clmax of 1.3 for both and Cd0 of 0.02 for both, now note the difference wing AR alone has on the L/D ratio one of the most crucial factors to high turn performance. (The higher the L/D ratio the better)

*Wing with AR of 8*

(1.3^2)/(pi*8*.85) = 0.0791093688

0.0791093688 + 0.02

Cd = 0.0991093688

1.3 / 0.0991093688 = 13.1168225

L/D ratio = 13.11

*Wing with AR of 6*

(1.3^2)/(pi*6*.85) = 0.105479158

0.105479158 + 0.02

Cd = 0.125479158

1.3 / 0.125479158 = 10.3602863

L/D ratio = 10.36
_______________________________

L/D ratio Differential: *35.9 %*

Additionally two graphs showing the difference in L/Dmax between a wing with an AR of 4 vs a wing with an AR of 9:

*AR 4*






*AR 9*


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## delcyros (Feb 14, 2008)

> The chart is easy to read, you just later added report on the EC1240 without me noticing it, and from it you can also see that the NACA 0012 EC1240 have VERY similar CL figures at the different Reynolds numbers.


Sorry for doing so but it took time to fully compile this post. However, there is not the information You seem to get from the charts. NACA 0012 and EC1240 have comparable Cl-max figures. But not at different reynold numbers (tests are for same reynold numbers) instead they show similar Clmax at different Mach fractions. Key aspect is that the NACA 0012 has better Cl-max than the Me-262´s basic airfoil at lower speeds (US&german tests. at RE= 5.000.000 and Mach = 0.1, the Cl-max is 1.40 for the NACA 0012 and 1.26 for the NACA 0009). The EC 1240 is comparable to the NACA 0012 and thus better than the Me-262´s airfoil at low speeds. It appears that the influence of the reynolds number is largest at low speeds and lowers towards Mach= 0.5. So the RAF test is reasonable for higher speeds.




> Also keep in mind that these tests were done with a wing of different planform and with a considerably lower AR, and as we all know CLmax increases with increased AR. The AR of ME-262's wing is 7.23.



*aspect ratio= span^2 / wingarea* (for tapered wings)

..and the aspect ratio of the tapered Vampire I wing is 7.08, not much different from the Me-262´s wing (actually 7.21). Note that the computations I use for Cl-approximation is three dimensional (lattice vortex method) and include planform, aspect ratio and other variables, already. This method is not two dimensional! The difference in aspect ratio between Vampire and Me-262 is tiny (ca. 1.9%).


To bring the discussion back on track, our early dispute was whether or not the Me-262 turns as good or better than the Vampire MK I. Soren´s thesis that the LE-slats help to turn the tide for the Me-262 has been questioned by myselfe. It appears that the Me-262´s wing has a lower Cl-max than the Vampire´s wing at maneuvering speeds. This is partly offsetted by the use of LE-slats. It also appears that the wingload for the Me-262 is much higher at combat weight and thrust to weight ratio are in the same ballpark for both planes (slight advantage for the Vampire at combat weight).


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## Arsenal VG-33 (Feb 14, 2008)

When I was a kid, I had a model of the Mistral, the French built version of the Vampire. I vaguely recall on the assembly sheet, the short aircraft history mentioning something about the Vampire/Mistral being capable of carrier takeoff/landing (or could be easily modified to do so). Anyone else heard of this? If it were true, that would be an advantage over the 262.


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## Soren (Feb 14, 2008)

Delcyros,

Why do you keep talking about the Me-262's wing tip ?? What does that have to do with anything ?? 

The wing tip always has the lowest Clmax critical AoA, hence the use of wing twist (Wash out) and slats on outer wing sections. 

The Me-262's wing root thickness ratio is 11% from where it gradually decreases along the span to 9% at the wing tip. The Vampire's wing thickness ratio decreases more sharply starting at 14% and ending at 9%. 

The automatic LE slats on the Me-262 help increase the lift critical AoA by 25%.

Furthermore I completely understand the charts and it is clearly illustrated that the CL figures are VERY similar between both airfoils at the different Reynolds numbers and speeds.


As to the Aspect Ratio of the wings, well you totally blew it there Delcyros! 

The Aspect Ratio of a wing is calculated likewise: (Span * Span) / Wing Area, very true.


Me-262: A = 21.7 m^2 Span = 12.51 m
DH Vampire. A = 24.34 m^2 Span = 11.58 m

So the Me-262's wing's AR is *7.23*, and the Vampire's is *5.5* !

Actually I'm quite surprised you could ever screw that up Delcyros as just by looking at the two wings it should've been very clear to you that the ARs are VERY different!


----------



## delcyros (Feb 14, 2008)

Soren said:


> Delcyros,
> 
> Why do you keep talking about the Me-262's wing tip ?? What does that have to do with anything ??
> 
> ...



Any meaningful discussion HAS to include the outer wings, not just the wingtips. You don´t want to have a stall there (...and the plane would enter a spin) so the reynolds number for the outer wing sections are non neglectable factors for lattice vortex analysis. The Me-262´s reynolds numbers for each section are ranging from 1.48 mill (wingroots) to about 0.8 mill., resulting in a mean, actual Cl-max in the range of in between 1.03 and 1.05 for Mach 0.1. without and around CL-max=1.29 with LE slats deployed (note that the actual Cl-max is lower as the maneuvering speed is higher than Mach=0.1 and thus the Cl-max is lower, too). In comparison the Cl-max of the EC 1240 under it´s re limitations is 1.19. THIS HAS SUBSTANTIAL IMPORTANCE FOR THE DISCUSSION. THE LE-SLATS DO NOT GIVE A 25% ADVANTAGE TO THE ME-262 (for each m^2 wingarea) BUT ONLY AN 8.2% ADVANTAGE. At 6.400 Kg combat weight, the Me-262´s wingload is 295 Kg/m^2 (adjusted for Cl-max of 1.29 at fully deployed LE-slats = 228 Kg/m^2) opposed to 259 Kg/m^2 at 5.430 Kg combat weight of the Vampire MK I (adjusted for Cl-max of 1.19 = 217 Kg/m^2). So despite LE-slats, the Me-262 has a higher, lift adjusted wingload. These results are derived from FORTRAN, Profill 2.20, Xwing and Mr. Ranis vortex software and adjusted for EC 1240/0640 (14% wingroot, 9 % wingtips) and NACA 0009 (11% wingroot and 9% wingtips) and their respective planforms.

*span^2* is the mathematical expression of *span * span*. Your ar calculation of the Vampire I is based on wrong facts.

RCAF.com : The Aircraft : deHavilland VAMPIRE

Vampire *MK I*:
span: 12.19m; wing area: 20.99m^2
aspect ratio: 7.08 (12,19^2 = 148,5961 / 20,99 = 7.07937...)


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## Soren (Feb 14, 2008)

I believe you're the one relying on incorrect data Delcyros. Just from looking at the a/c it's exceedingly clear that the AR of the Vampire's wing isn't even close to 7, the wing would be ALLOT more slender if that were the case.

All the sources I have indicate a Span of 11.58m and a wing area of 24.34 m^2.

Vampire

Now as to your CL estimates, well they're just as screwed up. You're simply not correctly reading the charts you yourself presented Delcyros, cause they clearly illustrate the high similarity in Cl between both airfoils at all speeds Reynolds numbers.


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## delcyros (Feb 15, 2008)

Soren said:


> I believe you're the one relying on incorrect data Delcyros. Just from looking at the a/c it's exceedingly clear that the AR of the Vampire's wing isn't even close to 7, the wing would be ALLOT more slender if that were the case.
> 
> All the sources I have indicate a Span of 11.58m and a wing area of 24.34 m^2.
> 
> Vampire



Bottom line is that Your source relate to the Vampire FB V, not our Vampire F MK I. I quote from Your link:



> Applies to:
> 
> 
> *de Havilland Vampire FB.5*
> ...



For the F MK I use the reference, I listed above.




> Now as to your CL estimates, well they're just as screwed up. You're simply not correctly reading the charts you yourself presented Delcyros, cause they clearly illustrate the high similarity in Cl between both airfoils at all speeds Reynolds numbers.


No, they don´t.


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## Graeme (Feb 15, 2008)

Arsenal VG-33 said:


> I vaguely recall on the assembly sheet, the short aircraft history mentioning something about the Vampire/Mistral being capable of carrier takeoff/landing (or could be easily modified to do so). Anyone else heard of this? If it were true, that would be an advantage over the 262.



I'm unaware of the Mistral being carrier capable, but as you know the Aquilon (Venom) certainly was, but now we're talking early 50's. However the FAA produced the Sea Vampire (F 20 and F 21) at the end of the war. The F 21 was used in trials on HMS Warrior involving undercarriageless landings on rubber matting. Eric Brown landed a modified Vampire on HMS Ocean on 3 December 1945...


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## Soren (Feb 15, 2008)

For crying out loud ! 

Delcyros, the only difference between the FB.5 and FB.1's wing is that one has square wing tips and the other has rounded wing tips, span and wing area is similar!

The site you reference simply by mistake misplaced the numbers 2 6 in the wing area specification, writing 226 sq.ft. instead of the true 262 sq.ft. and then converted that into metric getting 20.99 m^2 instead of the true 24.34 m^2.

The real specs for the Mk.I and onwards are:

Wing span: 11.58 m
Wing area: 24.34 m^2

Look at every other site for this, and if you're still not convinced then look at the profile of the different Vampire marks and compare them, and furthermore try comparing them to the Me-262's profile. That should be more than enough for anyone to realize that the AR's of both a/c are VERY different! 

Bottom line, the Vampire's wing is not even close to having an AR of 7!


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## Soren (Feb 15, 2008)

*Vampire Mk.I top profile:*





*Me-262 top profile:*





Should be endlessly simple and easy to note the big difference in AR between the two a/c's wings!


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## delcyros (Feb 16, 2008)

Soren said:


> Delcyros, the only difference between the FB.5 and FB.1's wing is that one has square wing tips and the other has rounded wing tips, span and wing area is similar!





No. The FB V has basically a F MK III wing with clipped wingtips, which has different properties with regards to planform in order to allow a larger internal fuel capacity. This new wing (originally with rounded tips in the Vampire F MK III) was first tested on a modified Vampire MK I in june 1945. Altough I have little geometric datas on the differences between old new wing, I am not in the position to proof them. Since You have casted them in doubt, it´s Your task. Note that IF the planforms were identic between FB V and F I wing, than the clipped wingtips would have made a LARGER wingarea for the unclipped FI wing necessary (in between 272 and 274 ft^2, ca. 25.2-25.3m^2). 226 ft^2 therefore hardly is a typo from 27x ft^2, my friend. It is not credible to use the shorter wingspan of the clipped MK V wings for MK I performance estimations, too.

de Havilland D.H. 100 Vampire I — Canada Aviation Museum
RCAF.com : The Aircraft : deHavilland VAMPIRE
Comox Air Force Museum Vampire

Btw, the max. overloaded fighter weight seems to be only 4.754 Kg without external stores! So even if You are right with the wingarea -from what I have been not convinced- the aspect ratio would be more like 5.8 to 5.9, but the wingload at overloaded fighter configuration drops from 259 Kg/m^2 of my original estimation (20.99m^2 wingarea and 5430 Kg MTOW) to only 188 Kg/m^2 (25.26 m^2 wingarea and 4.754 Kg MTOW). My lattice vortex computations would need to be redone for such a wing and I expect a Cl-max in the range of in between 1.13 and 1.16 for such a wing, which would end up the adjusted lift corrected wingload to only 165 Kg/m^2. Congratulations, Soren! You have found a way to show that the lift adjusted wingload of "Your" Vampire is even far lower than that of mine! It will turn rings around a Me-262 anytime!

BTW, comparing pictures from swept and unswept planes with regards to aspect ratio is given false impressions. although the aspect ratio as such is only a secondary indicator. The wingspan is the crucial component of the performance. This is because an airplane derives its lift from a roughly cylindrical tube of air that is affected by the craft as it moves, and the diameter of that cylindrical tube is equal to the wingspan. A swept back wing with thin chord has a notably lower aspect ratio than would the same wing have if it would be unswept.


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## Soren (Feb 16, 2008)

Nope, you don't fool me mr. spin doctor.

I don't buy your Cl estmations either, as the Cl of both wings are very similar as both have similar LE sweep Cl figures for the airfoils under similar conditions.

Also you can choose to ignore the facts about wing span and area if you like but then you're just making stuff up from then on. 

Finally let me ask you; Do you have any idea how the wing on the Vampire would look like if it had an AR of 7 ??!

Please play a little more with that program of yours to get an idea of how AR affects the shape of a wing and then compare the profile you get with the real thing, that should open your eyes.

Still can't believe you can't even see it with your own eyes from just looking and comparing shapes, geeez... even the FW190 Bf-109 have more slender wings!


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## Elvis (Feb 17, 2008)

Aw, screw that!

THIS plane could beat either of those two, hands down!






GO AMERICA!

(looks like the one my Dad took pictures of at Itami)







Elvis


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## DerAdlerIstGelandet (Feb 17, 2008)

Elvis said:


> Aw, screw that!
> 
> THIS plane could beat either of those two, hands down!
> 
> ...



Can you prove it? Back it up with facts please...

(You see Soren, I jump on other people too )


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## Soren (Feb 17, 2008)

Oh I know Adler, I know. I just like complaining


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## Elvis (Feb 17, 2008)

DerAdlerIstGelandet said:


> Can you prove it? Back it up with facts please...
> 
> (You see Soren, I jump on other people too )


Let me put it to you this way, how would the 262 or the Vampire fare against a Mig-15?
First Mig downing is attributed to an F-80.



elvis


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## Soren (Feb 17, 2008)

Yeah and a few were shot down by prop fighters as-well, so your point is ?

The P-80A was clearly inferior to the Me-262.


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## DerAdlerIstGelandet (Feb 17, 2008)

Elvis said:


> Let me put it to you this way, how would the 262 or the Vampire fare against a Mig-15?
> First Mig downing is attributed to an F-80.
> 
> 
> ...



That is not a very good arguement. That is nothing more than speculation. Lets hear some facts....


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## Seawitch (Feb 17, 2008)

Elvis said:


> Aw, screw that!
> 
> THIS plane could beat either of those two, hands down!
> 
> ...


This is a Bell XP59 Airacomet?
Then no, I just don't think so! 
What is it?


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## Elvis (Feb 17, 2008)

Seawitch said:


> This is a Bell XP59 Airacomet?
> Then no, I just don't think so!
> What is it?


Lockheed F-80 Shooting Star (might be a P-80, I don't know the age of the photo).
America's first operational jet fighter.

...and to the rest of you guys...I WAS JOKING

 



Elvis


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## kool kitty89 (Apr 9, 2008)

Delcyros, I'm pretty sure the 226 ft2 figure is a typo. The F.I's wing should be close to the 262 ft2 figure. (and the wing tips would have added very little, plus the wing was generally different, thinner iirc, which may have mean slightly lower area of same size wing) I think the F.III and later models modified wing (which was designed to carry more fuel and under wing tanks) was a bit thicker for this reason, though I'm not sure. 9either way the wing was pretty close in overall properties)

According to: de Havilland D.H.100 Vampire - History, Specifications and Pictures - World Military Aircraft
and de Havilland Vampire and Sea Vampire (1946 - 1969) military aircraft - Vic Flintham

The max speed is ~540 mph, but (though one lists the 2,700 lbf Goblin I) I think this applies to the 3,000-3,100 lbf Goblin II powered version. (of all later F.I's) I'd expect the original F.I to be somewhere around 520-530 mph.

Even if the Me 262 had a 25% higher max CL, lift loading would still be much better for the Vampire with it's much lower wing loading.

For the F.I:
Base Series Designation: de Havilland D.H.100 Vampire
Classification Type: Fighter
Contractor: de Havilland - UK - View All
Country of Origin: United Kingdom
Initial Year of Service: 1946
Crew / Passengers: 1
Production Total: 95* - View Totals Page

*Sometimes an estimate when actual production numbers
are not available. A value of 0 indicative of NA.

DIMENSIONS:

Length: 30.74 ft | 9.37 m
Wingspan/Width: 40.03 ft | 12.20 m
Height: 8.83 ft | 2.69 m
Empty Weight: 6,380 lbs | 2,894 kg
MTOW: 10,494 lbs | 4,760 kg


PERFORMANCE:

Engine(s): 1 x de Havilland Goblin 1 turbojet engine generating 3,100lbs of thrust. - Compare Stats

Max Speed: 539 mph | 868 km/h | 469 kts
Max Range: 730 miles | 1,175 km
Service Ceiling: 41,010 ft | 12,500 m | 7.8 miles
Climb Rate: 4,300 ft/min (1,312 m/min)

ARMAMENT:

External Hardpoints: 2
Armament:
4 x 20mm cannons

Up to a maximum of 2,000lbs of external ordnance. 



Now if we compare both a/c with max (clean) weight (full internal fuel and ammo) and their empty weights we have 3,800 6,400 kg for the Me 262A-1a and 2,894 4,760kg for the Vampire F.I (I believe the MTOW is w/out the 2,000 lbs Bombs, otherwise the fuel load would be too low to make sense)

For Soren's sake lets start with the empty weight comparison: wing loading: 175.1 kg/m2 /1.25(25%+ for slats)= 140.1 for the 262A-1a; 118.9 kg/m2 for Vampire F.I (with 262 ft2 figure).

And for thrust/weight: (empty) 262A-1a: .468 (for 2x 890 kp B-3 engines)
and .415 for the F.I Vampire (assuming thrust of 2,650 with some intake losses, there would be negligible exhaust losses due to the short jet pipe that was facilitated by the pod mounted engine twin boom design)


The loaded weight figures are more in favor of the Vampire due to the proportionally lower fuel load carried, though range was still similar due to the more fuel efficient engine. (SFC: 1.15 lbs/lbf hr for Goblin I opposed to 1.44 lbs/lbf hr for the 004B, a 25% greater specific fuel consumption, though this would have significantly improved with the 004D and E)


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## SoD Stitch (Apr 9, 2008)

Elvis said:


> Lockheed F-80 Shooting Star (might be a P-80, I don't know the age of the photo).
> America's first operational jet fighter.
> 
> ...and to the rest of you guys...I WAS JOKING
> ...



I'm pretty sure that's a P-80; IIRC, the F-80 had tip tanks installed.


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## kool kitty89 (Apr 10, 2008)

Firstly all P-80's were redesignated F-80's when the USAF was formed. (as were all other pursuit a/c in USAF service, ie F-51, F-47)

The P-80 had tip tanks too, basicly the same assortment as well, one thing was the Fletcher centerline tip tanks (mounted on the end of the wing tip insteas of under the tip) required a modified squared off wing tip with slightly reduced span. The first tanks to be used were the normal Lockeed tanks basically the same 150/165 us gal tanks as those of the P-38, though the P-80 couldn't hold the largest (300 gal) tanks for the P-38. The P-80A/B only used the Lockheed tanks iirc. (it was the Lockheed tanks that actuall reduced drag, increased lift, and improved roll rate when fitted)

The P-80C was modified to use several other larger capacity tanks (from JoeB's site):


> The F-80C bore the brunt of Shooting Star combat in Korea, most of the F-80As and B's either remaining stateside or going on duty in Europe. In service, many P-80C aircraft were fitted with two additional wing pylons, and provision for the mounting of sixteen 5-inch rockets were made. Service modifications included the use of either 265 US gallon under-tip tanks (sometimes named "Misawa" tanks after the air base in Japan where they were first introduced) or 230 US-gallon centerline tip tanks. When the latter type of tanks were carried, the wingtips were squared off, reducing the span to 38 feet 9 inches.




The "centerline" drop tanks are the Fletcher tanks usualy seen on pictures of F-80C's (the same tank was used as the F-84's tip tank) and are usualy present on T-33's as well, being bolted to the wings. (not dropable)

They are demonstrated here on these P-80A, B's and the T-33: 















But you are correct in thinking it's not an F-80, that is in fact a picture of the "Gray Ghost" which was the second P-80 prototype and the first XP-80A (the XP-80 "Green Hornet" was a completly different aircraft, being much smaller and powered by an early 2,400 lbf Goblin/Halford H-1 engine, the XP-80A was a redesign of the majority of the a/c with a new company model number and used the larger GE I-40 engine which was to become the J33). This was closely followed by the unpainted third prototype (2nd XP-80A) the "Silver Ghost." It was the XP-80A which would become the production P-80.


But this is all off topic...  And the P-80 vs Me 262 topic has been discussed ad nauseum. (in that case Soren's argument did prove correct)


----------



## Elvis (Apr 12, 2008)

Elvis said:


>





kool kitty89 said:


> that is in fact a picture of the "Gray Ghost" which was the second P-80 prototype and the first XP-80A (the XP-80 "Green Hornet" was a completly different aircraft, being much smaller and powered by an early 2,400 lbf Goblin/Halford H-1 engine, the XP-80A was a redesign of the majority of the a/c with a new company model number and used the larger GE I-40 engine which was to become the J33). This was closely followed by the unpainted third prototype (2nd XP-80A) the "Silver Ghost." It was the XP-80A which would become the production P-80.
> 
> 
> But this is all off topic...  And the P-80 vs Me 262 topic has been discussed ad nauseum. (in that case Soren's argument did prove correct)


I'll have to see if I can find the pics again, but if the pic I posted is the second prototype, then I think that's the one my dad took pictures of, while he was stationed at Itami.
The colour of the fuselage appears simlar, as best as I can remember.
It used to sit on the tarmac, under guard, surrounded by rope and stantions (think, as in "theatre ropes", if that makes sense).
Dad said the guards would let people walk right up to it, take pictures, gawk at it all day...as long as you stayed outside the ropes.
The pilots who flew it had a lot of fun with the 51's. 




Elvis


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## kool kitty89 (Apr 13, 2008)

The image is on wikipedia's P-80 page. 





When did your dad take pictures of it?

According to wikipedia The "Gray Ghost" was lost on a test flight on 20 March 1945.


The Lockheed insignia is a dead giveaway for its prototype status.


----------



## kool kitty89 (Apr 15, 2008)

Here's the profile of the 3 types of tanks the F-80C carried:


----------



## Elvis (Apr 16, 2008)

kool kitty89 said:


> The image is on wikipedia's P-80 page.
> 
> 
> 
> ...



KK,

First off, take anything you read on Wikipedia with a grain of salt, since the contents _can_ be altered by anyone.
However, supposing for the moment that the date you stated is correct (and I'm not saying its not, just that it should be research _past_ Wikipedia in order to verify it), then the plane my dad took pictures of was not the Grey Ghost.
Dad was sent to Itami in June of '46, so that plane would've already crashed.
From what I can remember, that is what it looked like, though.




Elvis


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## FLYBOYJ (Apr 16, 2008)

That picture is over Muroc (now Edwards)


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## FLYBOYJ (Apr 16, 2008)

Here's what it look like a few years later and closer to today...


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## Graeme (Apr 16, 2008)

Loss of the Gray Ghost


----------



## Soren (Apr 16, 2008)

That's fake (the picture that is)


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## FLYBOYJ (Apr 16, 2008)

Yep although Tony LeVier had that happen to him just south of Edwards - that's probably what it looked like!

"Revision" - I clicked on the link and it was about that incident! I got to know Tony in the late 1980s - his consulting office was next door to my ex-wife's office.


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## FLYBOYJ (Apr 16, 2008)

Graeme said:


> Loss of the Gray Ghost



Hey Graeme - net site.

BTW in the story, Highway 6 is now known as Sierra Highway. At one time it was the only road from Los Angeles to Edwards. Rosemond is now a small community right next to Edwards.

BTW Tony told me the turbine disk came apart and they actually found it in the town of Lancaster, about 20 miles to the south.


----------



## Graeme (Apr 16, 2008)

FLYBOYJ said:


> Hey Graeme - net site.



Photo and story from this site Joe...

The X-Hunters - XP-80A


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## FLYBOYJ (Apr 16, 2008)

I meant "Great Site."


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## kool kitty89 (Apr 16, 2008)

Elvis said:


> KK,
> 
> First off, take anything you read on Wikipedia with a grain of salt, since the contents _can_ be altered by anyone.
> However, supposing for the moment that the date you stated is correct (and I'm not saying its not, just that it should be research _past_ Wikipedia in order to verify it), then the plane my dad took pictures of was not the Grey Ghost.
> ...



Well was it Gray like that? But most of the early P-80s had this pearl-gray finish, including all YP-80A's and early production P-80A's some of the XP-80A prototypes were bare metal (ie Silver ghost) as well. (and the XP-80 was dark green, "Green Hornet")

Do you remember if it had the Lockheed insignia on the nose? (I think only the prototypes had this, not YP's)


----------



## Soren (Apr 17, 2008)

> First off, take anything you read on Wikipedia with a grain of salt, since the contents can be altered by anyone.



It can't be altered by anyone. But still it is a very good idea to take some of it with a grain of salt, esp. if no sources are listed.


----------



## comiso90 (Apr 17, 2008)

BBC NEWS | Technology | Wikipedia survives research test

The free online resource Wikipedia is about as accurate on science as the Encyclopedia Britannica, a study shows.

The British journal Nature examined a range of scientific entries on both works of reference and found few differences in accuracy.

Wikipedia is produced by volunteers, who add entries and edit any page.

But it has been criticised for the correctness of entries, most recently over the biography of prominent US journalist John Seigenthaler.

Open approach

Wikipedia was founded in 2001 and has since grown to more than 1.8 million articles in 200 languages. Some 800,000 entries are in English.

It is based on wikis, open-source software which lets anyone fiddle with a webpage, anyone reading a subject entry can disagree, edit, add, delete, or replace the entry.


We're very pleased with the results and we're hoping it will focus people's attention on the overall level of our work, which is pretty good
Jimmy Wales, Wikipedia founder
It relies on 13,000 volunteer contributors, many of whom are experts in a particular field, to edit previously submitted articles.

In order to test its reliability, Nature conducted a peer review of scientific entries on Wikipedia and the well-established Encyclopedia Britannica.

The reviewers were asked to check for errors, but were not told about the source of the information.

"Only eight serious errors, such as misinterpretations of important concepts, were detected in the pairs of articles reviewed, four from each encyclopedia," reported Nature.

"But reviewers also found many factual errors, omissions or misleading statements: 162 and 123 in Wikipedia and Britannica, respectively."

Wikipedia founder Jimmy Wales welcomed the study.

"We're hoping it will focus people's attention on the overall level of our work, which is pretty good," he said.

Writing style

Nature said its reviewers found that Wikipedia entries were often poorly structured and confused.

The Encyclopedia Britannica declined to comment directly on the findings; but a spokesman highlighted the quality of the entries on the free resource.

"But it is not the case that errors creep in on an occasional basis or that a couple of articles are poorly written," Tom Panelas, director of corporate communications is quoted as saying in Nature.

"There are lots of articles in that condition. They need a good editor."

Wikipedia came under fire earlier this month from prominent US journalist John Seigenthaler.

The founding editorial director of USA Today attacked a Wikipedia entry that incorrectly named him as a suspect in the assassinations of president John F Kennedy and his brother, Robert.

The false information was the work of Tennessean Brian Chase, who said he was trying to trick a co-worker.

Wikipedia has responded to the criticisms by tightening up procedures.

Next month it plans to begin testing a new mechanism for reviewing the accuracy of its articles.


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## Elvis (Apr 17, 2008)

kool kitty89 said:


> Well was it Gray like that? But most of the early P-80s had this pearl-gray finish, including all YP-80A's and early production P-80A's some of the XP-80A prototypes were bare metal (ie Silver ghost) as well. (and the XP-80 was dark green, "Green Hornet")
> 
> Do you remember if it had the Lockheed insignia on the nose? (I think only the prototypes had this, not YP's)



KK,

I'm thinking it was probably an early production model.
Yeah, colour looks the same as I remember...of course, we are talking about B&W photo's here. 



Elvis


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## Old Wizard (Apr 18, 2008)

This is interesting:
http://www.dreamtimeentertainment.com/onesheets/Coverup46.PDF


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## kool kitty89 (Apr 18, 2008)

Not completely accurate though, particularly on the dates...

It would be interesting to see actual data on the P-80/262 comparison though. And the often given example (with no source cited) appears to be with the XP-80, very different from the XP-80A and subsequent YP-80A's and production P-80A's. (the XP-80 was a different type, quite a bit smaller, and powered by a ~2,400 lbf British Halford H-1 engine, top speed being just over 500 mph)

As for the dates, it says the 262 is a "1938" a/c opposed to the "1946" P-80 and P-84. This is fairly correct on the P-84 though, but even in this case it's flawed as the XP-84 project started in 1944 and the first prototype completed in late 1945, flying at the beginning of 1946.

The P-80 and Me 262 dates were even further off, with the original development of what was to become the 262 starting in 1939 but changing many times through the first jet only flight of the V2 prototype in 1942. (still in tail dragger configuration)
The XP-80 program was initiated in 1943 after Lockheed had received data for the XP-59B (single engined Airacomet) and the Halford H-1, creating a much superior design to the XP-59B. The XP-80 powered by the Halford H.1B (Goblin) and was completed and began ground trials in late 1943. It flew at the beginning of 1944. But even before the XP-80 L-140 design had been tested the larger L-141 powered by the I-40 (J33) had been proposed and eventually became the XP-80A which flew in mid 1944.

Lockheed XP-80 Shooting Star
Lockheed XP-80A Shooting Star


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## Elvis (Apr 18, 2008)

kool kitty89 said:


> The XP-80 program was initiated in 1943 after Lockheed had received data for the XP-59B (single engined Airacomet)


I thought the P-59 was a twin engined aircraft?

...or is this a mis-statement...



militaryfactory.com said:


> Despite the fact that these were, in fact, two turbojet engines, the P-59 still did not contend well in head-to-head match-ups with the propeller-driven, piston-powered North American P-51 Mustangs.



I, too would like to see a comparison of P-80/ME-262 flight/combat performance stats.
Maybe we could limit it to first production models.
Maybe we need to start a new thread?



Elvis


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## kool kitty89 (Apr 19, 2008)

The XP-59B (Note: not P-59B, which was a slightly improved P-59A) was a parallel design by Bell for a single engined jet fighter. As Bell had their hands full, the prliminary stusy of the XP-59B design and this eventually led to the P-80 program, im combination with info on the Halford H.1B (goblin) turbojet.


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## kool kitty89 (Apr 19, 2008)

Bell P-59 Airacomet



> Although the Airacomet never saw service in its originally-intended role as a fighter aircraft, it nevertheless provided the USAAF with valuable orientation experience in the use of jet aircraft and furnished a nucleus of trained jet pilots.
> 
> The Airacomet was to have one other major impact on aviation history, one that is not generally recognized. Bell engineers undertook some initial work on a single-engined version of the Airacomet, which was designated XP-59B (not to be confused with the P-59B). It had a low-mounted wing and was to be powered by a single General Electric I-16 turbojet engine housed in the rear fuselage with an air inlet at the wing roots and an exhaust in the tail. However, the Buffalo plant was so busy with other projects that in late 1942 the USAAF transferred the preliminary drawings of the single-engined XP-59B to Lockheed, where it became the inspiration of the famed P-80 Shooting Star.


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## Elvis (Apr 19, 2008)

KoolKitty89, 

Thanks for link. I see what you're getting at now.



Elvis


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## johnbr (Apr 20, 2008)

I have all ways wondered whey the UK or the USA did not put there jet engine's on the me 262.For they had the MetroVick f2 axial engine.


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## kool kitty89 (Apr 21, 2008)

Or the Westinghouse J34 engines, developed from the J30 which flew on the FH Phantom prototype shortly before the War's end. (in late January 1945) The J34 was 25" diameter, 119" length, some 3,000 lbs thrust on early models and weighed some 1,100-1,200 lbs. It was in testing in 1945 and first flown in 1946 iirc.


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## Elvis (Apr 22, 2008)

johnbr said:


> I have all ways wondered whey the UK or the USA did not put there jet engine's on the me 262.For they had the MetroVick f2 axial engine.


I think the mentality at the time was seeing what the Germans had developed and then see if we (we=all allied nations studying this "machinery") could use that to our advantage.
That would be different from what you're saying and may not have occurred to anyone, simply because of the direction of thinking at that time.
What I always wondered about was why the swept wing/stabilizers concept wasn't tested on the P/F-80, as a means of improving its performance?
Maybe hindsight is 20/20, but that seems like one of the first things I would've explored, upon deconstruction of the ME-262.




Elvis


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## kool kitty89 (Apr 22, 2008)

For the re-engined Me 262, I was thinking for experimental purposes for testing the airframe. Plus for safety reasons for the unreliable 004's and small amount of spares.

And on a swept wing P-80: Lockheed F-80E


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## FLYBOYJ (Apr 22, 2008)

kool kitty89 said:


> For the re-engined Me 262, I was thinking for experimental purposes for testing the airframe. Plus for safety reasons for the unreliable 004's and small amount of spares.
> 
> And on a swept wing P-80: Lockheed F-80E




But then I think the next step was....

Lockheed XF-90


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## kool kitty89 (Apr 22, 2008)

Nice design, a bit overbuilt (with very thick skin and heavy duty aluminum forgings) though making it too heavy. The engines could have been a bit more powerful too. It had J34's with ~4,200 lbf AB, while there were varients of the J34 which could put out 4,800+ lbf AB (or 4,900 lbf like the X-3's), which the competing XF-88 did use. (which was lighter to boot) The XF-90 did have longer range than the others though, and was incredibly tough due to the overly heavy construction. One of the prototypes was used with testing of Nuclear explosions and survived. (with some warping, it's being restored to static display in damaged condition iirc)

But it doesn't really matter anyway since the whole penetration fighter project was cancelled, thus the winning XF-88 never entered service, though it was developed into the F-101.


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## Elvis (Apr 22, 2008)

KK,

Thanks for the info on the F-80E. Mr.Baugher comes through again, eh?

--------------------------------

FBJ,

Man, is that ever a sexy beast!
Reminds me of an F-101, back in the days when it was runway model and being shot for Sports Illustrated covers.
Yeowch!


Elvis


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## davparlr (Apr 22, 2008)

FLYBOYJ said:


> But then I think the next step was....
> 
> Lockheed XF-90



Shades of "Blackhawk"!


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## kool kitty89 (Apr 22, 2008)

That's he thought too:


> The Lockheed XF-90 experimental long-range penetration fighter of the early 1950s always reminded me of the planes flown by the Blackhawks, who were comic book heroes when I was a wee lad. Hawkaaaaaa......!




And here's the Nuclear tests:


> Work on the XF-90 was formally terminated in September of 1950. In 1952, the second XF-90A (46-688) was deliberately destroyed on the ground during a nuclear test at Frenchman's Flat in Nevada. The first XF-90A (46-687) was shipped to the NACA laboratory in Cleveland, Ohio in 1953. By this time it was no longer flyable, and was used for structural testing, exploring the limits of the extremely robust structure of the design. Presumably it was tested to destruction. In 2003, the hulk of the second XF-90 (46-688) was recovered by the USAF Museum from the Nevada nuclear test site. I assume that it will eventually be restored and put on display.


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## davparlr (Apr 22, 2008)

Elvis said:


> What I always wondered about was why the swept wing/stabilizers concept wasn't tested on the P/F-80, as a means of improving its performance?
> Maybe hindsight is 20/20, but that seems like one of the first things I would've explored, upon deconstruction of the ME-262.
> 
> Elvis



Probably because they recognized that the wing sweep on the Me-262 was to move the center of lift aft and not to improve performance at speed (which it must have done to a small extent).


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## Elvis (Apr 22, 2008)

The sweep must have _some_ performance enhancement qualities.
Both the F-86 and the F-84 picked up approx. 100mph over their straight wing counterparts, when they went swept wing, and both aircraft were subsonic (level flight).
However, you bring up a good point. That could very well be why they didn't go after the swept wing, to begin with.



Elvis


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## kool kitty89 (Apr 22, 2008)

The wing sweep of the Me 262 (as well as the DC-3, late Il-2, Me 163, XP-55, XP-56, Saab 21R etc) were not for trans-sonic and critical mach reasons, but the slight sweep (~17.8*) would have had some effect, albeit unintentional. (and only slight)

However German engeneers obviously did know the advantages of swept wings, and the Me 262 HG aircraft took advantage of this intentionally.
-The HG-I had a swept tailplane, low profile canopy and a standard wing except for a 35* LE sweep inlay section inboard of the nacelles. It was flight tested.
-The HG-II had constant 35* sweep with the same swept tail as the HG-I. (it was originally to use a V tail) It was completed but never flew. (damaged by bombing or ground accedent and never fully repaired iirc)
-The HG-III had a 45* sweep with the engines moved to the wing roots and the same swept tail. (HeS 011 engines were planned iirc) It did,'t leave the drawing board.

It was the HG design data that was utilized in the XP-86 project iirc.


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## johnbr (Apr 23, 2008)

What the XF-90 needed was a pair of ge 404 that would get it going.


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## kool kitty89 (Apr 23, 2008)

No way to big...  They thought of alternate engines but all required a considerable redesign to work.


The J34 was a very compact engine (25" diameter ~1,200 lbs) the most promising adaptation would be to the related Westinghouse J46 (29" diameter ~1,800 lbs with 4,000 lbf 6,100 lbf AB) but even that would have required a major redesign.


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## Elvis (Apr 25, 2008)

Not having been there at that time, its kinda wild to imagine how early jet technology must've seemed like "Jules-Verne-come-to-life", back then.
Those engines sound so small and underpowered, by today's standards, but were "cutting edge" at the time.

I wonder, if it had existed at the time, whether the J85 could've been used on any of those early aircraft (262, P/F-80, F-1, Meteor, etc.).
I don't think they were very big, but put out a good amount of thrust (2850lbs.-5000lbs., according to the GE website).

Does anyone know if any of those early engines took well to having afterburners attached to them?
Did it make much difference in their thrust?




Elvis


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## Elvis (Apr 25, 2008)

.


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## kool kitty89 (Apr 25, 2008)

The early whittle based designs (W.2 series, J31, welland, Derwent I-IV) ran too rich (by jet standards, as jets run very lean) to allow proper after burning. For the AB W.2/700 for the Miles M.52 supersonic a/c, a fan was added to the engine to provide sufficient airflow for the AB. (basically a rudimentary after burning low bypass turbofan)


And the J85 could have been used on many of the early designs, He 280, Me 262, Ho/Go 229, He 162, Meteor, and a few others. Often the engines were at the CoG so switching engine type wouldn't require ballast etc. 

The Me 262 Project's reproductions use J85's.


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## Elvis (Apr 26, 2008)

Groovy!

Thanks KK.



Elvis


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## kool kitty89 (Apr 26, 2008)

And another thing on the after burning, the Jumo 004 seems to have been adapted fairly well in the 004E. And the J35 and J34 were quite sucessful with after burners being produced in the early '50's. (the original designs originating from 1944-45, early if you include the TG-100 turboprop that the TG-180/J35 was developed from)


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## kool kitty89 (Apr 30, 2008)

But back on topic, according to The Incomplete Guide to Airfoil Usage the Me 262 used

NACA 00011-0.825-35 at the root NACA 00009-1.1-40 at tip.

The -35 and -40 are position of max thickness as % chord, the middle figure pertains to radius (and sharpness) of the LE of the wing. 9they are German modifications to the orginal naming system) explained here: Aerospaceweb.org | Ask Us - German Modifications to NACA Airfoils

But why use the 5-series naming system when a 0011 and 00011 airfoil should be the same. (both are symmetrical with no chamber -thus CL should be zero at an AoA of 0- and max thickness of 11% of chord, and by default would have max thickness at 30% chord. Why use a more complex naming system when there should be no difference.

Also shouldn't such an airfoil have a relatively low CLmax, particularly with the low thickness ratio? (it's similar in design to a laminar flow airfoil)


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## Soren (Apr 30, 2008)

The LE radius doesn't matter much when slats are fitted. The problem without slats is sudden and sharp stalls and low AoA's.


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## kool kitty89 (Apr 30, 2008)

OK but why the 5-series? ie 00011, instead of 0011, the figures Delcyros posted were for the 00xx 4-series airfoils.

And I'm pretty sure the overall shape (planform, aifoil section, area, span) are identical now that I've looked into it more. The difference was the internal structure was strenghthened with increased internal fuel capacity, this necessitated a new tail assembly. With the round tips it had a span of 40.0ft, area is unknown but probably ~270 ft^2. (not much of a change due to the small size of the tips clipped on the FB.5's 38' span with 262 ft^2) 

From de Havilland Vampire and Sea Vampire (1946 - 1969) military aircraft - Vic Flintham



> F Mark I The Mark I first flew (TG274) on 20 April 1945 with a square cut tail fin after modifications to the prototype to establish the best fin and rudder configuration. The first aircraft went to 247 Sqn from March 1946 and as production progressed improvements were introduced on the line. From the 40th aircraft the Goblin 2 of 3,100lb thrust was introduced together with auxiliary underwing fuel tanks and from the 51st machine the type had a pressurized cockpit and bubble canopy.
> Service Fighter 3, 20, 54, 72, 130, 247, 501, 600, 605, 608, 613 Anti-aircraft co-operation 595, 631 Training 1689 Flt; 202, 203, 208 AFS; CFS; 19 FTS; 102, 103 FRS; 226 OCU; RAFC Communications FCCS; 12 GCF; Acklington APS Other AFDS; CFE; ETPS; NGTE; WEE



and



> F Mark 3 The short range of the early aircraft was addressed in the Mark 3 which was built to specification F.3/47 and carried more fuel in wing tanks resulting in extended range (730 to 1,145 miles). The tanks caused stability problems which were cured by lowering the tailplane, extending its chord and changing the shape of the fin and rudder. The prototype was TG275 which flew on 4 November 1945 and the type joined 54 Sqn in April 1948.
> Service Fighter 5, 20, 32, 54, 72, 73, 247, 502, 601, 604, 605, 608, 614 Training CFS Communications 25, 602, 603; Chivenor, Odiham, Thorney Island SFs; Other AMSDU; 1, 4, 5 CAACU; CFE; 1 OFU; TEU Khartoum; TFU


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## Soren (Apr 30, 2008)

Probably because of the different angle of the trailing edge on the outer wing.


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## kool kitty89 (Apr 30, 2008)

What would be the difference between a 0011 and 00011 airfoil then. (the entire wing uses the 5-series 000xx according to the figures) Both have 0 chamber (and 0 chord chamber location), the same max thickness at the same location. THe only difference is that the 5-digit one specifies a CL of 0.

And it should be noted that the entire wing outboard of the nacelles is of the same airfoil section. NACA 00009-1.1-40 (just interesting)


Also if you assume the Vampire Mk.I and F.3 had an area of 270 ft^2 with 40.0 ft span (estimated from the 2' higher span than the 262 ft^2 clipped wing, possibly more area) 

AR is calculated to be 5.93 a bit better than you previously stated. And the wing loading of the Mk.I would be more than 25% lower than the 262 in same configuration. (full load clean configuration) at 10480 lbs gross weight (assuming the 270 ft figure) it would be 42.5 lb/ft^2 (~208 kg/m^2) compared to 6,400 kg Me 262 at 60.3 lb/ft^2 (294 kg/m^2); ~41% higher for the Me 262.


And for thrust/weight the 2,700-2,770 lbf engine would be very similr to the Me 262, with a small edge to the 262 with 004B-3/4 engines of 890 kp thrust. (8.73 kN). Nominal thrust on the Vampire with the Goblin I would be ~2,600-2,700 lbf. The losses from the Vampire's short, albeit angled, intakes should be minimal an exhaust losses should be nonexistant, total thrust loss probably only 2-3%. Reasonable considdering the XP-80 with its long and angled intakes and very long exhaust cut it's 2,700 lbf H-1B Goblin engine by nearly 10% down to ~2,460 lbf, not quite as bad on the Later XP-80A and dirivatives after they got the bountary layer bleeds. Similar losses were encountered on the He 178 with its long exhaust. A long ehaust having much more of an effect than the intake, cutting the 500 kp max HeS-3b down to ~450 kp. (one of the major reasons for external engin mounts of the early low thrust engines, putting no penalty on thrust, also the reason for the Vampire's design facilitating the minimal exhaust pipe length)

Though the Goblin II powered Vampire Mk.I (41 production model onward) wasn't built until the war ended it's pretty valid to compare to a 004D/E powered 262. The 004D had a nominal thrust of 930 kp (near 9,000 rpm iirc) by delcyros' figures, the 1,050 kp figure is at 10,000 rpm which was overrev. The 004E put out 1,000 kp nomimal dry thrust (1,200 kp AB iirc). The Goblin II put out 3,000-3,100 lbf (1,362-1,407 kp; 13.4-13.8 kN). Comparing the 2x 1,000 kp and 3,100 lbf (~3,000 nominal) the thrust/weight is very close.


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## kool kitty89 (May 7, 2008)

I wonder why they clipped the top of the Vampire's tail from the Spider crab (first/#1) prototype to the change in later prototypes and the Mk.I. (I know the changes in CoG among other changes resulted in the new tail on the F.3, but that's different, the F.3 had the same wing though)

The prototype's tail is clearly seen here with full triangular fins, they appear to be the same as the Mk.I's save the I had them clipped at the top. The F.3 also had a much lower tailplane, right aganst the booms, almost in the jetwash.

The taller tail should have offered better stability and spin characteristics. (the short fin was blanked in a sharp high AoA stall as Delcyros mentioned, creating a dangerous situation that could be hard to recover from)

The F 3's "guitar pick" fins (similar to the DH.88's fin) improved a lot of these characteristics though. (the much later T.11 trainer also got a new tail)

The #1 prototype and the MkI are clearly seen here: Vampire








Mk.I





F.3 vampire:






And here's some info on variants and differences: [1.0] Vampire Variants


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## Zyzygie (Jun 25, 2018)

"The Swiss Air Force operated 182 de Havilland DH.100 Vampire early jet fighter-bombers. The Vampire was the first jet fighter in the Swiss inventory and they were initially used for air defence..."

"...The last Swiss built Vampire fighter-bombers were retired from frontline service in 1974 with many kept in storage until 1990 but the trainer variants and converted single-seater target tugs soldiered on in use until 1990 (some 59 single seat fighters and 30 two-seat trainers were still on hand either in storage or operational). For an early Cold War jet aircraft that utilised wood in its design it sure gave plenty of years of valuable service to the Swiss and many other air forces around the world!"

Swiss Air Force Centre: de Havilland DH.100 Vampire – The First Swiss Jet Fighter

"...The Swiss liked the Vampire and its stable-mate the Venom so much that they kept them in service for much longer than anticipated, eventually retiring them in 1990 after a service life of almost 38 years! To achieve this, the Swiss extensively improved, modified, strengthened and refurbished their Vampires..."

de Havilland Vampire

I've read somewhere that a Vampire or two in Swiss service got involved in a hail storm which it survived, but which would have quickly taken out a turbojet with axial flow compressor.


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## Greyman (Jun 28, 2018)

RE: Vampire turn performance speculated on in the thread ...

_Turning Circles. The Vampire was found to be superior to the Meteor III in turning at all speeds. ... If the Meteor III is positioned on the Vampire's tail and both aircraft tighten up to a minimum turning circle, it takes approximately 1.5 turns to port for the Vampire to be positioned on the Meteor's tail. In starboard turns the Meteor seemed to be able to tighten up much more and it takes the Vampire a little longer to gain a complete turn on the Meteor.

The Vampire is superior to the Spitfire XIV at all heights. The two aircraft were flown in line-astern formation. The Spitfire was positioned on the Vampire's tail. Both aircraft tightened up to the minimum turning circle with maximum power. It became apparent that the Vampire was just able to keep inside the Spitfire's turning circles. After four or five turns the Vampire was able to position itself on the Spitfire's tail so that a deflection shot was possible. The wing loading of the Vampire is 33.1 lbs. per sq. ft. compared with the Spitfire XIV's 35.1 lbs. per sq. ft._

Tactical Trials - Vampire I
Central Fighter Establishment​


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