# Heinkel He-162 engine.



## Chocks away! (Jul 9, 2005)

I have heard this plane had various problems, from the position of the engine, to the wooden construction, to the tricky handling. Yet i have never heard about problems with the BMW 003. How come it wasn't fitted to, say the Me-262? That aircraft suffered a lot from those Jumos.


----------



## delcyros (Jul 9, 2005)

The main reason why it wasn´t regularly fitted in the Me-262 airframe was because the Jumo was avaiable earlier. A few prototypes of the Me-262 C were fitted with an BMW-003 R, a standart BMW-003 with added rocket assitance.
Originally the Me-262 was intended to be driven by BMW-003 A. In such a case the airframe could made much lighter (at least 350 Kg), the nacelles for the engines smaller (the BMW-003 had a smaller diameter) and therefore the whole airframe would benefit. 
Technically the BMW-003 had a better thrust to weight ratio, was much more reliable, had a longer lifetime and wasn´t that prone to flameouts by changing of throttle settings. But: it had not the same power output (800 Kp compared to 840 Kp (Jumo-004 A at 100%), 828 Kp (-004B1), 840 Kp (-004 B2), 890 Kp(-004 B-3/-4) and 930 Kp(-004D1). And another technical problem never solved in the -003 program was that it was impossible to restart the engine if it was once out (unlike the Jumo-004). 
On the other hand it wasn´t until very late in 1944 that BMW-003 have made reliable and if you remind the numbers produced you will find that the Jumo-004 was produced 6-8 times as much. There never were enough -003 to equipp all Me-262 airframes.At least two He-162 prototypes have been equipped with Jumo-004 D, even!


----------



## Chocks away! (Jul 9, 2005)

Hmm, that's a shame it would be great if Me-262s were reliable.


----------



## delcyros (Jul 9, 2005)

The unreliability of the Me-262 in general is overstressed a lot. If properly maintened and in case the pilot operates the Jumo´s in the way they had to be operated, the Me-262 is a reliable platform.
Accidents are not uncommon for early jets, the P-80 program proved this. Nobody would say that the P-80 is unreliable.
You may observe the same difficulties for the early Me-262, and moreso for the He-162. Esspeccially the reliability of the Salamander is greatly underestimated. The fuselage was made of metal, the short wings of wood. The same was done for the Me-163 and worked fine. The Ta-183 and Ju-EF128 should also have wooden wings. the Vampire even has a wooden fuselage! The number of accidents for the He-162 program was quite high, but not as high as the Me-262 EKdo´s. With proper improvements both planes would become more reliable. The later Jumo´s (-004 B3/4 and D) worked as well as the BMW-003, while the Jumo´s never reached such a high degree of efficiency (esspeccially because they cannot overrew, the BMW-003A and E could do so: for 30 sec. 923 Kp thrust).


----------



## DaveB.inVa (Jul 9, 2005)

delcyros said:


> The later Jumo´s (-004 B3/4 and D) worked as well as the BMW-003, while the Jumo´s never reached such a high degree of efficiency (esspeccially because they cannot overrew, the BMW-003A and E could do so: for 30 sec. 923 Kp thrust).




Thats interesting, I never knew those engines could do that. Do you have any more info about this? Any websites that provide specs?


----------



## Chocks away! (Jul 9, 2005)

Why would you make a jet out of wood! It sounds opsurd today and yet it worked fine...


----------



## me262 (Jul 9, 2005)

Chocks away! said:


> Why would you make a jet out of wood! It sounds opsurd today and yet it worked fine...


the reason for this was that the precarious situation on strategic materials casued by the naval blockade and the constant bombing by the allies, that is the reason for the shoter life of the early jet engines, lack of heat resistant materials, and thats is the difference between the british and german engines, plus that the technology was in their infancy


----------



## FLYBOYJ (Jul 9, 2005)

Although I question the reliability of both aircraft (the -262 for the engines and using dissimilar metals in it's construction, and the -163 for the use of wood which if damaged must be carefully repaired, we've debuted these points before) The use of wood ushers in something to think about that was probably not even fully realized back then - it absorbs radar waves!


----------



## me262 (Jul 10, 2005)

not really absorbes, just it do not bounce back the radar impulse, an hence do not show in the radarscreen!1
another plane made with wood and the forefather of the b-2 is the HO IX/ Go 229


----------



## evangilder (Jul 10, 2005)

We have had this discussion before and to say that the Horten is the forebearance to the B-2 is not correct. Jack Northrop had been designing his wing around the same time and if _any[/y] aircraft can make that claim, it would be the N9M, not the Ho IX or the Gotha.

The N9M became the XB-35, which later would be developed into the XB-49, a jet powered flying wing. It is said that the XB-49 could turn inside of the P-80 chase plane!!! _


----------



## me262 (Jul 10, 2005)

the horten brothers build their first wing sailplane in 1933, their first twing pusher in 1937 and the first jet engine in 44.
about the claim about the performance of the xb 49, it suffered of inestability that is the reason why it did not entered in service


----------



## delcyros (Jul 10, 2005)

I do agree that the Ho-IX isn´t the forefather of the B-2. Some conceptual similarities are there but both are indigenous projects.
Dave, try
www.warbirdsresourcegroup.org/LRG/he162.html
for verification of the additional thrust for BMW-003-E2 under overrew conditions(2000+ lbs or 9,02 KN thrust). I have not yet found any website to cover exclusivley the jet engine technology aspects, but this page brings it to the He-162 directly.
Overrew wasn´t something unusual, the original Jumo-004 A, designed of rare metals and much chromium could be overrewed to at least 1000 + Kp thust instead of the 840 Kp thrust under 100% power setting.
The later -004B version had problems with vibrations at 9000 rpm, which made it impossible to overrew the engine in the way, the -004 A did (later the max rpm had to be reduced to evevn 8.700 rpm).
The BMW-003 was free of such problems because the smaller diameter of the turbine wheels allowed much higher rpm´s and caused no vibrations. 
Several british designs had initially the same problems (W-2B, Dervent-IV) but in the end they have been mastered, mainly thanks to the supeior alloys used for the turbine stage and combustion chambers.
The average lifetime of a BMW-003 combustion chamber was about 200 hours, even the larger BMW-018 jet engine was thought to operate for at least 80 hours at 800 degrees C. For comparison: The improved Jumo-004D had- according to Anselm Franz- a lifetime of about 60 hours.


----------



## DaveB.inVa (Jul 10, 2005)

evangilder said:


> It is said that the XB-49 could turn inside of the P-80 chase plane!!!



I've heard that before and certainly believe it. As Im sure you know many big bombers were able to handle better than smaller fighters and such at higher altitudes. There are many references of B-36's being able to turn inside faster jets... if the jets could even get to the B-36's altitude. Paul Tibbets in his book describes mock dogfighting a P-47 at high altitude in a B-29. He said every time the P-47 got near his tail he just had to bank hard into a turn. When the P-47 would try to follow, it would stall out and fall away! This is pretty much how the Lancaster survived with its corkscrew. 

It always has suprised me just how manuverable those big bombers and transports really are!


----------



## Chocks away! (Jul 10, 2005)

me262 said:


> Chocks away! said:
> 
> 
> > Why would you make a jet out of wood! It sounds opsurd today and yet it worked fine...
> ...


 Yeah I know I was just thinking aloud so to speak


----------



## KraziKanuK (Jul 10, 2005)

According to Gunston in his aero engine book the 004B was good for ~30 hr TBO while the Welland and Derwent were good for 150hr TBO. Both the English engines were type tested to 500hr.


----------



## DerAdlerIstGelandet (Jul 10, 2005)

I believe all jet engines of that time were not as reliable as they wanted them to be. The just lacked the materials. This was especially true though in the German engines and those of the Me-262.


----------



## FLYBOYJ (Jul 10, 2005)

DaveB.inVa said:


> evangilder said:
> 
> 
> > It is said that the XB-49 could turn inside of the P-80 chase plane!!!
> ...



The B-47 was extremely manevuable and there was one planned tactic to deliver nukes in a "lob," flying straight up and allowing the weapon to arc toward the target while the aircraft made its getaway.  Eventually these types of maneverus put great stain on the wing attach structure and the -47 starting developing cracks in this area.


----------



## me262 (Jul 10, 2005)

delcyros said:


> I do agree that the Ho-IX isn´t the forefather of the B-2. Some conceptual similarities are there but both are indigenous projects.


 i see the aproch like this:
the H0 IX/Go 229 was made with plywood and hence almost invisible to radar, at that time they did not imagine this concept, and the b-2 invisible to radar


----------



## plan_D (Jul 10, 2005)

_"...not really absorbes, just it do not bounce back the radar impulse..."_

If the RADAR waves do not bounce back off the wood then the wood has absorbed the waves.


----------



## CharlesBronson (Jul 11, 2005)




----------



## evangilder (Jul 11, 2005)

Yes the B-49 did suffer from a few problems, and politics. The thought of a dogfight between a P-47 and a B-29 sounds funny, but the altitude makes all the difference for that. Somewhere I have a pic of a B-47 from my dad's days in the air force. 

The B-2 has radar absorbing paint, as does the F-117. What does get reflected back is about what a small bird reflects.


----------



## the lancaster kicks ass (Jul 11, 2005)

whilst in comparison most modern fighters have the radar cross section of a small house.........


----------



## delcyros (Jul 11, 2005)

Charles, the He-162 with V-tail is the subtype He-162 A-6, not He-162 Z.
The A-8 subtype with Jumo-004 D engines would weight up to 3000 Kg fully equipped. The plus in poweroutput was thought to increase the top speed to 918 Km/h or 570 mp/h. The thrust to weight ratio would be decreased to 0.31 instead of 0.32-0.33 in case of BMW-003 E (overrewed), but the plane would be able to sustain it´s top speed for a much longer time. But this is still better than anything except for the Me-163 and Meteor MK IV.
To the turbines:
The alloys used were tinadur (15% chromium, 15% nickel, 5% titanium and steel) for Jumo-004 B1 and cromadur (without nickel but therefore traces of manganese) for Jumo-004 B4/D/E. The first was thought to be more heat resistant but worser to produce, so it was replaced by cromadur, which could be easily welded instead of deeply drwan for the hollow turbine blades. In the end the later was easier to cool and therefore much more heat resistant than tinadur.
The disadvantage of the Jumo´s in general, beside of the average lifetime was its prone to flameouts under 6.000 rpm. This is mostly because of the fuel regulation system at lower rpm (easy to burn out the turbine blades if too much fuel is injected at low rpm):
A gear driven pump that produced a linear amount of fuel proportion to the engines rpm, the pilots throttle was directly connected to a bypass valve that would recirculate unwanted fuel. Fuel then passed to a centrifugal speed governer that operated another bypass valve. However, if the engines rpm was under 6.000 rpm (set to idle), the speed governer did not take into effect and the throttle bypass was the only fuel flow regulation. The pilots throttle also was connected to a governor by a pressure spring and would regulate the governers rpm setpoint this way. At full throttle, for example, the rpm of a Jumo-004 B4 was at 8875 rpm. Under 6.000 rpm the pilot had to be very careful, because without the governeor it was easy to allow to much fuel entering the combustion chambers and thereby burn them out.
So there can be a dissimilarity between engines rpm and air flow. The BMW-003 had a similar layout but in addition a device that consisted of an aneorid capsule across the compressor stages. This "accelerator valve" regulated the fuel flow in correspondence to the air flow (by pressure) and the governeor had less importance. In the end the actual air flow and spool up time was taken into account, so that the BMW-003 throttle could be handled less gingerly. The Jumo-004 on the other hand had a more sophisticated system to regulate the exhaust nozzle, while the BMW-003 exhaust nozzle was manually controlled.
Further improvements have been under work (some ceramics and thermocuple to reduce fuel flow if temp limits are to be exceeded). 
That´s why type testings means something close to zero, the most limiting factor of the lifetime of early jets have been careful handling in the start and spool up phase. That´s one reason why the Jumo-004 B-1 had around 10-25 hours lifetime while the -004 B-4 had around 25-50 and the BMW-003 around 200.


----------



## DerAdlerIstGelandet (Jul 11, 2005)

evangilder said:


> The B-2 has radar absorbing paint, as does the F-117. What does get reflected back is about what a small bird reflects.



This I have heard to, but I have read that the B-2 was not as successfull in this in that it was actually seen as the size of a plane on radar. I do not know the truth in this though. Could you clarrify for me.


----------



## plan_D (Jul 11, 2005)

I've read it has a small signature for the size of the plane but not small enough to avoid RADAR detection - but the shape of the plane allows to easily fly under RADAR.


----------



## DerAdlerIstGelandet (Jul 11, 2005)

That is what I read thankyou for making more sense out of it.


----------



## evangilder (Jul 11, 2005)

The best way to describe it is take a playing card and hold it out in front of you. If it is facing you, you see plenty of it. Now look at the edge, you see less. That is pretty much how it is with the B-2. It has a small profile, so if it is heading toward the radar, the cross-section is pretty small, and the radar absorbing paint helps with that. Now if the radar is pointing at a B-2 that is banking or climbing, the cross-section is quite a bit bigger.


----------



## DerAdlerIstGelandet (Jul 11, 2005)

Nice way to put it.


----------



## evangilder (Jul 11, 2005)

Thanks, I try to use a simple explanation. Easier to understand for everyone.


----------



## FLYBOYJ (Jul 11, 2005)

DerAdlerIstGelandet said:


> evangilder said:
> 
> 
> > The B-2 has radar absorbing paint, as does the F-117. What does get reflected back is about what a small bird reflects.
> ...



This is correct about the B-2 but along with ECMs that are rarely discussed, the B-2 achieves an almost invisible RCS.

I've had the opportunity to work on both aircraft. In mt opinion the -117's RAM material and stealth "system" seemed a little more resilient when compared to the B-2. Also the B-2, being much larger is prone to much more RAM material damage and rework.

Many auto body and fender mechanics were employed by Northrop during the assembly of the aircraft. They were known as "surface prep mechanics."


----------



## CharlesBronson (Jul 11, 2005)

delcyros said:


> Charles, the He-162 with V-tail is the subtype He-162 A-6, not He-162 Z.



All right , thanks, I dont have too much books about this plane to compare the data.


----------



## me262 (Jul 11, 2005)

all the z models consisted of 2 fuselages married by means of center wing, AFIK the only one that got in production was the He 111 Z, another example was the Me 109 Z, i'm not sure if this Me got any prototype, others planed : do 635, the he 162, the Ju 290


----------



## delcyros (Jul 14, 2005)

Never mind, Charles. 
After what I read, the BMW-003D (1.100 Kp at 100%) schould replace all BMW-003 A and -003E in later deliveries of the Salamander.
It had a better compressor (the same BBC manufactured one of the -003C) with higher compression and a two stage turbine with some further improvements, like a much reduced specific fuel consumption. It also weighted less than 640 Kg and could very well enhance the performance of the He-162 (or Ar-234C).
I suspect that this couldn´t happen prior to mid 45 and it would be attended moreso in the swept winged versions of the He-162.
But even without it, the He-162 was a first class fighter. If you compare it with Meteor MK-I and MK-III or YP-80A or Vampire (´45). It has the best powerload and the best thrust to weight ratio (second only to the Me-163 and....Surprise! P-59 Airacobra!!!), a decent climb, an excellent top speed (second only to Me-163 and P-80), an unchallanged roll rate (particularly at high speeds) and crit Mach figure. It also has shortcomings: Range, armement and stall behavior (until tail redesigns in jan. 45) beside of material problems like production quality and so on.
It wasn´t until the arrival of the Meteor MK-IV in late 45 that the allies had something superior in the jet field (just my opinion).
Wrong?


----------



## FLYBOYJ (Jul 14, 2005)

delcyros said:


> It wasn´t until the arrival of the Meteor MK-IV in late 45 that the allies had something superior in the jet field (just my opinion).
> Wrong?



My opinion Del is that although more manevable than the P-80, six 50 cal all nose concentrated would have made toothpicks out of the -162s wings!  I think the -162 would of been the Zero of early jets.


----------



## delcyros (Jul 15, 2005)

Some point, Flyboy.
But now we are digging in the field of durability / survivability of the airplanes. I had the opportunity to read something in advance of this.
He-162: 
* comparably high wingload and powerload (wl:around 235-244 Kg/m²)
* wooden wings with metal rudders
* metal fuselage
* designed to sustain a max of 8g (+) and 5 g (-) (destruction limit is about 3 g higher)
* engine mounted above the ss fuel tanks
* ejection seat
* the hittable surface is tiny (below those of the FW-190A)


Meteor-III:
* comparably low wingload and very low powerload (wl: around 177 Kg/m²)
* all metal structure
* ss and protected fuel tanks mounted in the wings (as the engines) and in the fuselage
* designed to sustain a max of 7g (+) and 4g (-) (again, not the destruction limit)
* hittable surface is large (more than two times those of the He-162)

P-80:
* medium wingload and low powerload
* all metal structure
*ss fuel tanks mounted in front of the engine
*designed to sustain a max of 7.5 g(+) and 4g (-) (destruction limit higher)
* hittable surface is medium (around 1.7 times those of the He-162)

ergo: While the He-162 has virtually no armor protection, except for the pilot, the airframe (made of wood) sustains more G forces and is more durable (surprise: A Meteor MK-III crashed because of structural limits during testflights, the wing of MK-IV was enforced (adding 320 Kg to it´s weight) but the FMK-8 needs even further reinforcements to the wings structure... 
The P-80 design is much more balanced and If (!) hit by 0.50 M2 (the 0.50 M3 wasn´t serially installed prior to early 1946), damage would be severe but it needs repeated hits to kill the He-162 (as for the Bf-109). Hitting the fuel tank wouldn´t have a big effect. Otherwise could the twin 20mm HE rounds blast a P-80 in pieces with ease. Hitting the fuel tank would lead automaticly to the P-80´s destruction (the gazes would forced to move to the engines and inflame in the end. The problems with unsealed fuel caps underlined the problems, it lead to many accidents). Hitting the wing could cause sereouse damage by deforming the wing surface (blast effects). I have seen pictures of Me-262 beeing hitten in the main fuel tanks without serious effects (it needs a HE round or (questionable) an incidentary round of a 0.50 cal gun to inflame the bad burning german low grade jet fuel.


----------



## FLYBOYJ (Jul 15, 2005)

Good points! But I have to say a 20mm round hit anywhere isn't heathy. A 20mm hit to a F-80 fuel tank would have to be a direct hit. That area is extrememly reinforced and there is a huge screen in front of the P-80s engine. The P-80s unsealed fuel caps were addressed when many of the A B models were moded into the "C" configuration in the late 1940s.

I believe a concentrated 50 cal hit anywhere on a -162 would destroy it immediately. You're talking 6 50s with a spread of about 3 feet.


----------



## delcyros (Jul 15, 2005)

Not automaticly. Something very important is the spacial density of fire. The 6 0.50 M2 have a very good density (esspeccially because they are concentrated in the nose and not in the wings) -moreso the 0.50 M3- and they can harm the He-162 if prolonged hitten in the fuselage or the wing. 
each round will probably went right through the structure, leaving a hole in the metal fuselage or the wooden frames of the wing. That´s it. If you concentrate enough holes in a certain point (remember, the He-162 is a tiny target, the approaching speeds are high and it´s also highly agile...), the structure will desintegrate (you may cut off the tail for example). Jets are much more simple, esspeccially the engines compared to piston planes and I suspect they can take a huge amount of 0.50 cal rounds (happened in Korea, too), the same goes for the P-80. By the way, the weaponry of the P-80 is well placed and strong enough to deal with anything, I am not going to deny this. However, the 20mm HE rounds of the MG 151/20 have a different effect and the blast effect, if hit, will destroy and inflame anything up to 15 cm beyond the impact point (except if stopped by armor) by means of blast effects. This is probably not enough to deal with heavy bombers but for fighters, esspeccially for the P-80 it´s more than enough to deal with. And less hits are needed to ensure destruction, also. The blast effects are very worrisome for the metal structures in general (esspeccially the wing) as testshots with MG151/20 on metal and wooden wings prooved.
The He-162 could be compared with the Zero, but the Zero missed two important performances, which lead to their fate: A good climb and a good dive capability. The He-162 has it. And while it is true that the plane is nearly unarmored (as was the Zero), it is much more rugged ( it sustains more G forces even with a higher wingload compared to P-80 and Meteor) and not that prone to inflamable by hits.


----------



## FLYBOYJ (Jul 15, 2005)

delcyros said:


> The He-162 could be compared with the Zero, but the Zero missed two important performances, which lead to their fate: A good climb and a good dive capability. The He-162 has it. And while it is true that the plane is nearly unarmored (as was the Zero), it is much more rugged ( it sustains more G forces even with a higher wingload compared to P-80 and Meteor) and not that prone to inflamable by hits.



Agree!


----------



## delcyros (Jul 15, 2005)

The P-80 also was an excellent design, well balanced, fast and quite agile. In the end it was maybe a bit too heavy for it´s engine (or otherwise underpowered) and I estimate that four 20mm instead of six 0.50 would make a better punch, too.
Who knows? The fuselage had a huge diameter, also (depended on the engine). The main problem, beside of air flow seperation at the air intake (causing some flamouts at high g maneouvering) was the fuel regulation and distribution/containing system. But these problems were common for many 1st gen jets.
The Meteor MK III was (my opinion) easy prey for either, He-162 or Me-262.
The MK-IV on the other hand would have been great. Such climb and acceleration impressed me much.
All allied designs miss some aerodynamic points to keep a high maneoverability at high speeds. And the crit mach figure of them is also under average, leaving their opponents in the comfortable situation to break at their own decision.


----------



## FLYBOYJ (Jul 15, 2005)

delcyros said:


> The P-80 also was an excellent design, well balanced, fast and quite agile. In the end it was maybe a bit too heavy for it´s engine (or otherwise underpowered) and I estimate that four 20mm instead of six 0.50 would make a better punch, too.
> Who knows? The fuselage had a huge diameter, also (depended on the engine). The main problem, beside of air flow seperation at the air intake (causing some flamouts at high g maneouvering) was the fuel regulation and distribution/containing system. But these problems were common for many 1st gen jets.



I got to fly T-33s. If you pulled high Gs you could hear a rumble around the air intakes and I was told you could flame the aircraft out if you did something really crazy. The fuel system problems (on both F80s and T-33s) were fixed in the late 40s, early 50s.

I agree with you on the 4 20mms. I think Lockheed offered a study on this in during the Korean war period.

The engine bay is cavernous, but I think the diameter of all the engines were about the same. Its funny, I've worked in T-33s and Mig-15. when the tail is pulled on both aircraft and you're looking forward in the engine bay its very similar in appearance.


----------



## delcyros (Jul 16, 2005)

Could be an explenation that the J-33 engine of the P-80 led to the development of the RR Nene (which became copied and renamed RD-45 in case of the Mig-15)?
A Nene modified P-80 would have been intersting, as well. 
The problems with fuel containings have been fixed, later, yes. The airflow seperation was (I must say mostly) under controll in mid 46, when Lockheed decided to suck off the whole boundary air flow around the air intake. This added some further weight, but it worked fine (while it never succeded in the whole problem, as your experiances show...).


----------



## plan_D (Jul 16, 2005)

The J-33 didn't lead to the development of the Rolls Royce Nene - the power of the 4000 lbs engines of the U.S made the British designers realise they were thinking too small, that's all.


----------



## delcyros (Jul 16, 2005)

That´s exactly what I wanted to say:
There was wide cross influence in the engine department over there.
The british designers shared their Whittle units and I believe later also the early Ghost engines, which led to the development of the J-36 from Allison Carmers. The next step was a US one: Realising that the poweroutput of the Ghost engine could be improved much by larger dimensions and some further improvements (particularly in the fuel regulation and turbine stage), the US designers went on the drawing board and began to design the J-33. British technicians, as you said, found this design in advanced stage when they visited the US facilities and relaized that more poweroutput is possible, also. This led to the RR Nene (and later to the down scaled Dervent V).
Without the J-33 program, the British would have moved much slowlier(maybe in another direction, also). And taking this into account, it is reasonable to say that the J-33 led to the RR Nene.


----------



## plan_D (Jul 16, 2005)

The J-33 led to the development of a larger engine. The U.S scientists had no influence on the design of the Rolls Royce Nene - nor did the J-33 itself.


----------



## delcyros (Jul 16, 2005)

I can agree in this. The main layout of the J-33 was originated in the Ghost, also. The main layout of the Nene, while beeing said to lay on the J-33 is otherwise also Ghost based. So it´s british, I think.


----------



## plan_D (Jul 16, 2005)

And no one is going to disagree that the RD-45 was a direct copy of the Rolls Royce Nene engine - so that's that settled. 8)


----------



## delcyros (Jul 16, 2005)

Yes, and even a bad made copy...


----------



## FLYBOYJ (Jul 16, 2005)

Hey, you got to give credit where credit is due - sure the Ruskies copied the Nene. Although they had an actually engine given to them, just duplicating it isn't that easy if they couldn't duplicate the materials its made from. Soviet spies were invited into the RR factory wearing soft sole shoes. If any of you were ever in a machine shop that makes aircraft components, there are metal chips thrown everywhere from the various machines. The Ruskie spies simply walked over to the machines that were producing Nene components and allowed the metal chips to become embedded into their shoes - INGENIOUS!

No way were the RD-45s compatible to any western centrifugal flow engine in terms of reliability. The Soviets just came up with something real simple - rather than attempting to get 1200 or even 2000 hours out of one of their engines, just "throw away the hot sections at 300 or 600 hours! At that point you eliminate the need for specialized personnel to examine the engine at 300 or 600 hour intervals (like we do in the west), specialized equipment and facilities to do these inspections and you could also train relatively unskilled labor to disassemble and replace hot sections very easily.

The finest genesis of the Nene/ J-33/ RD-45 saga lies with the Czech-built M701. Although only putting out 2000lbs thrust, this engine was probably the finest centrifugal flow engine produced in terms of reliability, producibility and maintainability. This engine has it's origins from the RD-45 and we already know where that came from. I've worked on Nenes, J-33s and -701s and I could tell you the -701s are bullet proof and way more reliable although the first ones were produced 13 years after the RD-45. In my oppinion the M701 is what was sought from early centrifigual engines in the mid 1940s!


----------



## plan_D (Jul 16, 2005)

It's hardly worth mentioning if it came from the Nene that was bench tested in October 1944! It was extremely reliable, powerful and durable back then. 

By 1947 Britain was already well on their way to more powerful engines - the Avon for one was in development that would soon produce 24,000 lbs (rounded)!


----------



## FLYBOYJ (Jul 16, 2005)

plan_D said:


> It's hardly worth mentioning if it came from the Nene that was bench tested in October 1944! It was extremely reliable, powerful and durable back then.
> 
> By 1947 Britain was already well on their way to more powerful engines - the Avon for one was in development that would soon produce 24,000 lbs (rounded)!



Agree - but by then RR engineers left the centrifigual flow engine design behind, they knew where the real power was!


----------



## CharlesBronson (Jul 16, 2005)

Delcyros wrote:



> While the He-162 has virtually no armor protection, except for the pilot,



the 162 not even had an armoured windshield....


----------



## me262 (Jul 16, 2005)

FLYBOYJ said:


> plan_D said:
> 
> 
> > It's hardly worth mentioning if it came from the Nene that was bench tested in October 1944! It was extremely reliable, powerful and durable back then.
> ...



are you refering to the axia flowl jet engine?( a german invention)


----------



## FLYBOYJ (Jul 16, 2005)

me262 said:


> FLYBOYJ said:
> 
> 
> > plan_D said:
> ...




Yes I am but your statement about the axial flow engine is WRONG - 1921 Maxime Guillame patented the Axial-Flow turbine engine


----------



## plan_D (Jul 16, 2005)

It was probably being developed or at least written down in theory before then by the same man - it certainly was _not_ an invention of the Germans. 

In fact - it could all be said that Sir Isaac Newton was the founder of the jet engine but we won't go that far. The jet was not new to the 1940s - in fact the real theory began during World War 1 - and Whittle first wrote his theory on it in the early 1920s! The only reason Britain was not well advanced beyond the rest of the world was because the RAF did not accept the idea! And then the idea was given away to the rest of the world in 1930 (after Whittle patented it) - giving the rest of the world to start developing the idea that Stern and Whittle had practically invented.


----------



## FLYBOYJ (Jul 16, 2005)

plan_D said:


> It was probably being developed or at least written down in theory before then by the same man - it certainly was _not_ an invention of the Germans.



Absolutely - I read somewhere when Whittle started his engine development he stayed away from thr axial flow concept because of complexity and costs.



plan_D said:


> In fact - it could all be said that Sir Isaac Newton was the founder of the jet engine but we won't go that far. The jet was not new to the 1940s - in fact the real theory began during World War 1 - and Whittle first wrote his theory on it in the early 1920s! The only reason Britain was not well advanced beyond the rest of the world was because the RAF did not accept the idea! And then the idea was given away to the rest of the world in 1930 (after Whittle patented it) - giving the rest of the world to start developing the idea that Stern and Whittle had practically invented.



In 1923 an English engineer published a paper that stated turbine powered aircraft were unpractical can can never be achieved.


----------



## plan_D (Jul 16, 2005)

It was jealousy from the Head of Engineering in the RAF that prevented the jet engine becoming more sooner. I cannot remember his name but he was writing his theories on the jet engine and it took his approval to get the RAF to accept it - he didn't give his approval because he'd been so wrong all that time and was jealous of Whittle who had got it so right while being much younger. 

It's sad really that personal feelings get in the way of things like that.


----------



## FLYBOYJ (Jul 17, 2005)

I heard the same theing - Whittle was an engineer who "Walked the Walk" and "Talked the Talk." He was able to explain to you the aerodynamics of a wing design (for example), show you how to construct it, and then go out and fly the aircraft. A remarkable man!


----------



## delcyros (Jul 17, 2005)

Yes, the axial jet engine conception isn´t a german invention, they have been the first to design, build, test and fly one but the theories behind these conceptions were much older. This shouldn´t reduce the pioneering aspect, however.
The largest axial jet engine on paper (as far as I know) was under construction by Daimler Benz from sept. 1943 on. They wanted to redesign their DB-007 for a much larger unit, DB-016, a construction chart note some 16.000 Kp thrust (around 35.000 lbs) for a twelve stage compressor, three stage turbine engine with 18 combustion chambers. Design went not very far, I am not sure if the scaled down test engines ever left the drawing board, I just know that drawings have been under consideration of several meetings from late 1943 till wars end. I expect that the difficulties to build a full scale unit would have been beyond the possibilities. Under normal conditions it would take some further 3 years to come to a solution. The construction charts show some interesting design features: thrust redirection for break , a large fan and so on, interesting!
The armor protection of the He-162 consisted of the back plate of the ejection seat and some reinforcement in front of the cockpit panels. That´s all. The bubble blown canopy had no protection (a bullet proof glass was foreseen in the more armored subtype A-3/A-4.


----------



## DerAdlerIstGelandet (Jul 19, 2005)

The Germans were having eneogh problems with there Jumo's They did not need to even think about a 30000lb thrust engine!


----------



## delcyros (Jul 19, 2005)

My mistake. It´s not 16.000 Kp but 13.000 kp (I just checked the drawing of the DB-016), that are still something around 26.000 lbs of thrust.
I agree totaly, Adler. But I think, if we count the latest Jumo developments also, that the main problems have been fixed for their Jumos: reliability by means of more sophisticated alloys for the -004B4 and -D as well as -E. I expect that DB was doing something more pioneering in their concepts than military useful for the next years. Some points like surface cooling systems, engine controll and engine geometry was very advanced. Most modern commercial jet engines have similar aspects.


----------



## DerAdlerIstGelandet (Jul 20, 2005)

The Germans needed to overcome there metal alloy problems and they would have been fine.


----------



## me262 (Jul 20, 2005)

DerAdlerIstGelandet said:


> The Germans needed to overcome there metal alloy problems and they would have been fine.


the problem was supply!!!!
they have to look for alternative alloys, but none was good


----------



## delcyros (Jul 21, 2005)

They haven´t been far away from a major breakthrough. The Reichsmaterialprüfamt had not that much options but an improved tinadur as well as a steel based alloy was in test phase for the turbine wheels. Nethertheless it would increase the weight in any case....


----------



## DerAdlerIstGelandet (Jul 22, 2005)

They had the right ideas and everything but as was stated supplie of materials was not eneogh.


----------



## Vahe Demirjian (Jan 15, 2020)

The Heinkel company envisaged an He 162 variant powered by Argus pulsejets in the event that normal jet fuel was in short supply.


----------



## CATCH 22 (Jan 15, 2020)

Vahe Demirjian said:


> The Heinkel company envisaged an He 162 variant powered by Argus pulsejets in the event that normal jet fuel was in short supply.
> 
> View attachment 566810
> View attachment 566811


At last - another thread revived out of the dark past!
Vahe, did you build this model? Cool! What scale is it: 1:48 or bigger? Who's the manufacturer? Are the Argus-engines aftermarket or "from scratch"? What paints did you use? IMHO the RLM 76 is a tad lighter, but that could be my computer - what do you think? What does the marking M 42 represent? Are the Balkenkreuze and the Svastika decals or painted? There is no Werknummer (serial) on the tail - do you know a possible matching Werknummer (W.Nr.) for this particular a/c? Can you show the underside of the model as well?


----------

