You are just miss understanding the point I was making which was mainly about available thrust. The Merlin eventually produced 2,000 BHP, Mitchell would have produced a much different design based on a 2000BHP Merlin and Variable pitch props. It is common here to quote the difference between a Spitfire MkIX and a P-51B/C or D which had the same Merlin engine, but it was a much different Merlin to that of 1936. A P-51 with a Merlin MkI, II or III and a wooden two blade prop would struggle to get off the ground at all, but it wasn't designed to, it was designed a few years later when planes all had constant speed props and 1100-1200BHP. I am not moving goal posts, I am saying how much goal posts moved between 1934 and 1940. This is borne out in later enquiries by the USA into UK aircraft engineering standards, basically why UK aircraft were lighter, they were lighter because they had to be, so the engineering standards sailed "closer to the wind" to the edge of what was safe and reasonable.
1941: the best airframe between the s/e fighters?
- Thread starter tomo pauk
- Start date
Shortround6
Lieutenant General
Well, The Spitfire VC carried about twice the firepower of a 109F or early G, While one Spitfire cannot be in two places at once needed two 109s to carry a bit more ammo than a single Spitfire is not exactly efficient. The Spitfire had room for more fuel.
In a similar way the Mig-3 was a rather expensive way to get one 12.7mm and two 7.62 guns into combat.
It can be a plus, it rather depends if the single engine type is able to be developed or runs into a wall development wise.
Shortround6
Lieutenant General
Look at the test reports for the early Spitfire and Hurricane.
Spitfire Mk I K.9787 Trials Report
The Merlin II & III were 1030hp engines at altitude, (16,250ft plus RAM)
but even with constant speed props they were 880hp engines at sea level using 87 octane fuel. in high speed flight (plus RAM)
However the fixed pitch wooden props killed that. For take-off and climb it was even worse, much worse. They may have had 880 hp at sea level but actual take-off and climb was done at much less than 3000rpm or 2600rpm (max continuous?)
Report listed above has the Spitfire using 2200rpm or less at 3,000ft or below and using 6.4lbs of boost. The engine never gets above 2475rpm, in part because the plane never goes faster than 213.5mph below 20,000ft while climbing and turning the prop faster would just cause it thrash the air producing even less thrust even though more power was going to the prop.
The fixed pitch prop even hurt speed at the lower altitudes because the engine could not run at full rpm without loss of thrust.
The two pitch prop helped but not as much as some might believe.
from Spitfire Mk I K.9793 Trials Report
"for this setting and normal take-off procedure the climbing speed reaches 170 m.p.h. (A.S.I.), and the r.p.m. 2850 at 2,000 ft. The change over to coarse pitch at this speed and height reduces the engine r.p.m. to 2070 at +6¼ lb. boost. Speed should then be increased to 185 m.p.h. - the best climbing speed in coarse pitch."
Rpm in the climb never exceed 2440rpm. RPM in high speed level flight was also restricted some what.
In fine pitch the airspeed is not to exceed 170mph ASI unless the engine is throttled for fear of overspeeding the engine.
Once the constant speed props were fitted climbs were done at 2600rpm and 6.4lbs of boost and level flight could use the full 3000rpm at all altitudes.
The engine was capable of making much more power at the lower altitudes than the early propellers could turn into thrust.
Spitfire Mk I K.9787 Trials Report
The Merlin II & III were 1030hp engines at altitude, (16,250ft plus RAM)
but even with constant speed props they were 880hp engines at sea level using 87 octane fuel. in high speed flight (plus RAM)
However the fixed pitch wooden props killed that. For take-off and climb it was even worse, much worse. They may have had 880 hp at sea level but actual take-off and climb was done at much less than 3000rpm or 2600rpm (max continuous?)
Report listed above has the Spitfire using 2200rpm or less at 3,000ft or below and using 6.4lbs of boost. The engine never gets above 2475rpm, in part because the plane never goes faster than 213.5mph below 20,000ft while climbing and turning the prop faster would just cause it thrash the air producing even less thrust even though more power was going to the prop.
The fixed pitch prop even hurt speed at the lower altitudes because the engine could not run at full rpm without loss of thrust.
The two pitch prop helped but not as much as some might believe.
from Spitfire Mk I K.9793 Trials Report
"for this setting and normal take-off procedure the climbing speed reaches 170 m.p.h. (A.S.I.), and the r.p.m. 2850 at 2,000 ft. The change over to coarse pitch at this speed and height reduces the engine r.p.m. to 2070 at +6¼ lb. boost. Speed should then be increased to 185 m.p.h. - the best climbing speed in coarse pitch."
Rpm in the climb never exceed 2440rpm. RPM in high speed level flight was also restricted some what.
In fine pitch the airspeed is not to exceed 170mph ASI unless the engine is throttled for fear of overspeeding the engine.
Once the constant speed props were fitted climbs were done at 2600rpm and 6.4lbs of boost and level flight could use the full 3000rpm at all altitudes.
The engine was capable of making much more power at the lower altitudes than the early propellers could turn into thrust.
Exactly my point, and later with the MkII Spitfire, the increased horsepower was not turned into a higher top speed it was turned into better climb/take off performance and from that better performance at combat speeds. In some ways the early top speed figures for both Spitfire and Hurricane must have been propaganda kidology and maybe the same for the early Bf109s because the top speed is made with a propeller that is no good for take off and climb, though obviously they can take off and climb, but not very well.
Shortround6
Lieutenant General
Well, it is all good if both sides are using fixed pitch props. Both have the same disadvantage. 
Once the propeller race starts things can change very fast.
Once the propeller race starts things can change very fast.
Shortround6,
Excellent post.
Is your insinuation that the Spit Vc carried too much firepower and some of that space should have been turned into fuel tanks, or are you making a straight comparison to the 109F / early G and that they made the trade off of more gas vice more firepower? Maybe I'm reading too much into this. On another note I'm curious if the RAF made a conscious choice of more guns & less gas vice the other way around regards the Vc?
Cheers,
Biff
Shortround6
Lieutenant General
You may be reading too much into it. Small as the Spitfire was it still had a much bigger wing than 109, even the clipped wing Spitfire had around 33% more wing area. Which leaves room for guns/ammo. The MK V never got fuel tanks in the wings but the volume was there in leading edge for the MK VII and some of the Griffon powered planes to put a pair of 12-14 gallon tanks in. Later Spits got a slightly large fuselage tank and some of the later two stage planes could be fitted with rear fuselage tanks (not really for use in combat) while the 109 seemed to top out at 400 liters of fuel. (88 Imp gal) perhaps more could have jammed in had the Germans really needed a longer ranged fighter? The 109 fuselage guns went just in front of the cockpit which rather spoils things for a fuselage tank on/near the CG.
In the early days the Spitfire may have been more weight limited than volume limited. The 109 may have been the reverse. For some reason the Germans never put guns of any sort inside the wings of the 109 after the E model. They didn't put any fuel in the wing either.
In the early days the Spitfire may have been more weight limited than volume limited. The 109 may have been the reverse. For some reason the Germans never put guns of any sort inside the wings of the 109 after the E model. They didn't put any fuel in the wing either.
It's a curious thing why the Germans did some of the things they did regarding aircraft, and in particular fighters. It would seem they would have been better off to have switched to all 190s and killed off the 109 line. More growth potential, better visibility, better landing gear arrangement. The fog of war, ego's, bad assumptions, and intelligent, resilient adversaries does not a fools game make.
Cheers
Biff
But the Fw190 wasn't "sorted" until 1941/42 and it wasn't better than the 109 in all respects even then. Quantity has a quality and Germany was already geared up to make lots of 109s. The Typhoon could have been a much better plane than it was but the RAF preferred more Typhoons than a better Typhoon, allowing efforts to be concentrated on a "super Typhoon" called a Tempest.
Shortround6
Lieutenant General
In theory you are probably right. In practice it may have been much more difficult.
At one point there were 7 or 8 factories tooled up for the 109, including Focke-Wulf (Jumo 210 powered versions) this may have dropped to 5 factories later on???
At any rate the Germans had a large investment in 109 tooling and production lines and after June of 1941 not much extra time to change a factory from one type of aircraft to another without a loss of production they could ill afford. The 109 was a useful fighter even if not the best Germany could produce.
Try to pick a year or even 6 month period when Germany could get by with hundreds fewer fighters produced than historically even if after that time period the average German fighter was a better machine?
At one point there were 7 or 8 factories tooled up for the 109, including Focke-Wulf (Jumo 210 powered versions) this may have dropped to 5 factories later on???
At any rate the Germans had a large investment in 109 tooling and production lines and after June of 1941 not much extra time to change a factory from one type of aircraft to another without a loss of production they could ill afford. The 109 was a useful fighter even if not the best Germany could produce.
Try to pick a year or even 6 month period when Germany could get by with hundreds fewer fighters produced than historically even if after that time period the average German fighter was a better machine?
I agree. The US didn't slow down the P-38 line to make the improved K version and we weren't being bombed around the clock.
Cheers,
Biff
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Germany also didn't ramp up aircraft production until they were in serious trouble.
*IF* they had production numbers in 1939/40 like they did in 1944, then perhaps, they could have afforded to take one factory offline to start production of a different type.
*IF* they had production numbers in 1939/40 like they did in 1944, then perhaps, they could have afforded to take one factory offline to start production of a different type.
cherry blossom
Senior Airman
- 556
- Apr 23, 2007
The Germans may have made a decision in 1940 to build a large air force for 1944 to prepare for a battle with a large Anglo-American air force (The Wages of Destruction by Adam Tooze, chapter 12). Thus the low production over 1940-2 may be because resources were devoted to building factories and synthetic fuel plants.
If you want an alternate history possibility, you could ask what if they had realized that they could not match the Anglo-American numbers and had tried for a qualitative superiority by giving priority to jet engines and jet aircraft.
windhund116
Senior Airman
- 360
- Jul 3, 2017
Bf-109F4.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
While that sounds interesting, we need to look at their aircraft production numbers in 1938/39, when they were in the process of starting a war.
Less than 8,300 aircraft (of all types) manufactured with a single-shift, 5 day work week. This is not how you go to war.
By 1944, they were working around the clock as an act of desperation, while bombs were falling on their factories, producing nearly 40,600 aircraft (many of which never made it to the front).
They had several years to ramp up production for "battle with a large Anglo-American Air force" before they invaded Poland.
And history shows that the German leadership didn't take Jet technology seriously until their reverse of fortune.
- Thread starter
- #36
Agreed all the way. Those are the points that put the Spitfire as having a better airframe vs. Bf 109.
Yes. The switch to two 20mm cannons was too late there - in 1942.
Even without poaching the bits & pieces (mostly engines and guns) from the Bf 109 into the much expanded Fw 190 production, there was a lot of potential war material that was basically wasted with fiascos like the DB 605/610 Me 210/410 and He 177. Just the early cancellation of DB 606 and 610 production, that went into thousands, would've feed many thousands of DB 601E and 605A engines for Fw 190s.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
And for the love of God, stop trying to make everything a dive-bomber!
The Ju87, Fw190F and even the Ju88 proved more than capable of the task.
pinehilljoe
Staff Sergeant
F4F-3, I like Martlets and Wildcats
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