Mistakes in Aviation

[red admiral]

Instead of developing the Whirlwind, it would most likely have been easier to put more tanks into the Spitfire to increase the range. It was done historically but there was no need for mass production of the variant as bomber command had already switched to night bombing. Really, I think the bombers are going to be shot down in droves at this stage in the war no matter how many fighters are put up alongside them. By 1944 when the 8th AF joined in properly losses are still marginal even with hordes of escorts and a weakened Luftwaffe. Spitfire Mk III with better altitude performance, cleaned up for more speed and with clipped wings for better roll rate.

The mid-wing engine mounting like the Meteor is actually more efficient than the underslung method, but structural considerations are more important. It would depend on the dimensions of the HeS engines and the location of the wing spars as to whether it would fit.

[Marcel]

Originally Posted by Flyboy2

Just curious,
How did the He-100/112 stack up against the Me-109?

The He112 lost to the Bf109 in a direct comparisment. The A version lost because it was clearly an inferior A/C (open cockpit and too complex). The B version was quite good, but never received the DB engines and kept stuck with low power Jumo engines. It performed reasonably well with the Hongarian and Spanish airforces but was obsolete during WW@ as it was never developed further as the Bf109.
The He100 was a potential very good aircraft. Major probem was the cooling system of the engine. Heinkel used an evaporation cooling but it was too complex. Gave the He100 a good topspeed (400+ mph, even with a DB601), though and a longer range than the contemporary Bf109E. Could have been useful in the BoB. The intended production model used a normal radiator, don't know the performance of that plane.

[kool kitty89]

The He 100 was also much easier to build than the He 112.


I know the mid-wing mounting is more aerodynamically efficient, but it requires a curved spar with exra reenforcement to be as strong as an underwing mount, adding some weight. Wing-root or fusalage mounted engines would be the best though. But the underwing mounting on both the 280 and 262 (as well as the He 162's mount) allowed a wide variety of engines to be acomedated with the only restriction being diameter. (for ground clearance) And all the class I engines in development could be acomedated. (the 004 being the largest in diameter iirc) In the case of the Meteor all the engines tested were about the same diameter, save for the Metrovic F.2/1's. The Goblins were longer and heavier but not significantly larger in diameter than the W.2 type engines, and the Derwent I was slightly smaller in diameter than the Welland as well.

The mid-mounting would need a redesign to the wing, certainly. It should also be noted that the HeS 6 engines were only about 39 in (~1.0 m) in diameter, a bit smaller than Whittle's designs (which stayed about the same diameter from the W.1 to the W.2/700, abeit gaining weight) though they were a bit heavy. (420 kg, similar to the Derwent)

[SoD Stitch]

Originally Posted by kool kitty89

The He 100 was also much easier to build than the He 112.


I know the mid-wing mounting is more aerodynamically efficient, but it requires a curved spar with exra reenforcement to be as strong as an underwing mount, adding some weight. Wing-root or fusalage mounted engines would be the best though. But the underwing mounting on both the 280 and 262 (as well as the He 162's mount) allowed a wide variety of engines to be acomedated with the only restriction being diameter. (for ground clearance) And all the class I engines in development could be acomedated. (the 004 being the largest in diameter iirc) In the case of the Meteor all the engines tested were about the same diameter, save for the Metrovic F.2/1's. The Goblins were longer and heavier but not significantly larger in diameter than the W.2 type engines, and the Derwent I was slightly smaller in diameter than the Welland as well.

Yes, I have heard that the under-slung nacelles turned out to be a blessing in disguise; more FOD to worry about, but servicing and changing an engine was a lot easier with it only a foot or two off the ground. And, also, as you pointed out, redesigning the nacelle (and the engine attachment points) was much easier with the under-slung design, which is why it was so easy to convert the -262 to the Junkers Jumo 004 engine in place of the BMW 003.

[kool kitty89]

The Metor was licky enough to have multiple centrifugal designs of similar diameter. While the further Whittle W.2 derivitives (eg, Welland, Derwent, Derwent V) were all specifically made to be of similar diameter, it was lucky that the Goblin also fit. Without the Goblin the Meteor would have flown even later. (thanks largely to Rover's incompetence)

[Evil_Merlin]

Originally Posted by SoD Stitch

IIRC, my understanding is it was in many ways a superior aircraft to the Bf 109, but Heinkel rubbed somebody's feathers the wrong way (Milch? Udet?) and lost the contract to Willy, partly for political reasons (another instance of Nazi Germany's "crony favoritism").

Two fold I think.

1.) Heinkel was a pain in the ass.
2.) The He 100 used the same engine as the Bf 109. This is one of the primary reasons the Fw 190 made it into production.


The He 100 was the fastest prop driven plane until the Corsair F4U hit.

[kool kitty89]

Not so much Heinkel was a pain in his own right, but he wasn't hapy with the Nazi establishment and they werent happy with his private projects.

The RLM also tended not to like a/c that weren't built for a specification. The !09 had already beaten the He 112 and the He 100 was late competition that wasn't realy made by RLM request iirc.

Similar with the Fw 187, a privately initiated project presented to the RLM and then forced into a destroyer configuration which it wasn't really meant for. It still outperformed the Bf 110, but there was no reason for the 2nd crewman. They also forced Jumo 210 engines on it. But Fw wasn't a "pain" to the RLM as Heinkel, but Messersmitt had a virtual monopoly on fighters at the time and it took considderable effort to break the RLM of this.

As said the main reason the 190 managed to get through is that it used a different engine.

Udet, who wasn't realy one for politics was often supportive of Heinkel's projects and showed an intrest early on with his jet developments, particularly the He 280:

During contract negotiations with theRLM, Udet, who was supportive of Heinkel and who had recog-nized that Heinkel needed engine manufacturing capability andskilled manufacturing manpower to compete with the establishedengine companies, made Heinkel a gentlemen’s agreement that ifthe He 280 succeeded in flying before April 1941 Heinkel couldbuy the Hirth Motoren company in Stuttgart.By the end of 1939 the HeS 30 progress was very slow andHeinkel, concerned of the adverse impact on the He 280 program,approached Dr. von Ohain to develop a backup solution. Dr. vonOhain’s solution, designated the HeS 8A, was a design based onthe HeS 3B but with an axial diffuser and a straight through flowcombustor. The engine program was done under a RLM contractgiving the engine the first RLM designation of a German turbojetthe 109-001. It was not without risks because the specification ofthe aircraft limited the engine diameter and therefore the axialdiffuser function and efficiency together with the straight throughcombustor became very critical. Luckily for Heinkel, von Ohain’sHeS 8 engine managed to meet the minimum requirements andwas ready in time for the first flight of the He 280 which tookplace in late March 1941. The He S 30 program still sufferedseveral problems including a mismatch between the compressorand turbine. Thus, it is thanks to von Ohain’s HeS 8 that the He280 flew on schedule and the RLM allowed Heinkel to purchaseHirth Motoren company which could then give the Mueller teamsupport with the HeS 30 program.

But of course Messersmit and the RLM weren't quite so hapy with this and political disputes delayed the transaction and hampered development of the HeS-8 and HeS-30.

After the demonstration flight of the He 280 Heinkel finallyreceived permission to purchase Hirth–Motoren21which was areputable manufacturer of reciprocating aero engines and turbo-chargers located at Zuffenhausen near Stuttgart. This acquisitionwas fraught with politics, with Heinkel’s rival Messerschmitt re-portedly delaying the acquisition for several months.22With theacquisition of Hirth, Heinkel had access to the engineering capa-bilities and manufacturing know-how of this small but wellknown engine company.

from: Using ASME format

[Burunduk]

In USSR in my opinion was a mistake to abandon Polikarpov I-185 (as before very progressive I-17 was abandoned and I-200 was transferred from Polikarpov to Mikoyan).

Also, stopping production of Tu-2 in 1942 was a mistake.

[kool kitty89]

I believe that was caused by politics too.

[red admiral]

Originally Posted by kool kitty89

Without the Goblin the Meteor would have flown even later. (thanks largely to Rover's incompetence)

But squadron service wouldn't have been changed. The Goblin Meteor was an interesting footnote, but not important, similar to the post-war Meteors with Nene and Sapphire engines. Rover managed to delay the in service date of the Meteor by two years - quite an achievement.

[kool kitty89]

Yes, and the Goblin was better used for the Vampire as well. (it was probably good that DH kept their Goblins, save for those sent to the XP-80 project) If there'd been more intrest the Vampire by the Air ministry it may have seen servise sooner.

The Vampire was a better design IMO as it could do more with less thrust/weight and was all-around better in terms of practicality and performance. Of course, the Meteor would have been 2 years ahead in development if it weren't for Rover...

Both England and Germany made some stupid mistakes like that with their jet programs. (ie canceling Heinkels class I engines)
On the other hand the US jet program went rather smoothly, albeit more than 2 years late in the game and getting a head start with Whittle's design. However, if we look a little further back we can see that the US made on of the BIGGEST mistakes of all: somewhat like the Soviets, the US had a number of jet/rocket reasearch project in the 1930's, in particular a NACA program which progressed to about 1939 and then was abandoned as "impractical." Another jet/rocket program was also started, but focused primarily with small designs for RATO/JATO. And thus the US lost any chance at getting into the feild nearly as early as others. In fact the NACA was still favoring ducted fan/motorjet designs with the new development projram in 1941. (the only real development from this program was with Westinghouse and Became the J30, the first all American turbojet engine to run, and also one of the best performing engines of the War with excelent thrust for its size: 1600 lbf at 19 in diameter and under 700 lbs weight)

[maut9r]

One of the biggest errors in the US effort was never getting Merlin's in the P-38. Several groups of Merlin P-38's sure could have helped things out over Europe until the P-51B arrived.

[kool kitty89]

What do merlins have to do with anything?

The problems were with the engine occling system, sometimes becoming overeffective or with radiator flaps jamming. (the overcooling caused the coolant and oil to circulate too slowly and the engine could overheat or seize)

There were also problems with the cocpit heatin. (lack therof) And problems with the intercoolers (inside the outer wings' leading edge) being inadequate and vulenerable.
Then there's the compressibility problems at .68 mach... But a good pilot could avoid these and even dive after an enemy if he kept speed well regulated. (throttle back) The dive flaps solved this but still limited speed to .68 mach.
Roll rate was also mediocre, and poor at high speed.

Most of these problems were solved with the P-38J and all the improvements
were present in the late production J models, including dive flaps and boosted ailerons. (with compeditive roll at low-medium speeds and excelent roll at high speed)

[FLYBOYJ]

Originally Posted by maut9r

One of the biggest errors in the US effort was never getting Merlin's in the P-38. Several groups of Merlin P-38's sure could have helped things out over Europe until the P-51B arrived.

A myth....

The fact remains the brass in the ETO did not like the P-38 and Merlins or not it wouldn't of changed things much....

[freebird]

Originally Posted by maut9r

One of the biggest errors in the US effort was never getting Merlin's in the P-38. Several groups of Merlin P-38's sure could have helped things out over Europe until the P-51B arrived.

No, the mistake was foolin' around with the prototype in a PR stunt and crashing it before proper tests could be done, set the program back at least a year....