Mistakes in Aviation

[kool kitty89]

Alot of the designers were on the right track or ahead of their time (Heinkel with jets for example) but the RLM had some crazy mindsets. Like no real contingency for defensive weapons and heavy bombers which doubled as dive bombers! (hence the He 177)

And Heinkel may not have been that well liked by the RLM, but it was his projects that jump started jet development and led to independent projects at Jumo, Junkers, BMW, Diamer Benz, (engines) and Messersmitt.(Me 262)

 

[Flyboy2]

Yeah, but imagine what would have happened if his good designs saw more widespread use (He-219)

 

[kool kitty89]

I'd thought so too, but check some of the Nightfighter threads. The He 219 isn't all as good as it seems on paper.

The Ju 88 was probably the most practical and effective all around night fighter. Almost as fast as the Mossie, a prooven design long in use. Multiple roles. Beter than the Bf 110 IMO.

In fact if you've got the Ju 88 and the Fw 187, there's nothing the Bf 110 can compete with.

 

[Watanbe]

hmmm although it did see some limited service, i reckon the Westland Whirlwird should have been given more of a chance. Although to be fair its hard to argue that it was a mistake because other excellent planes filled its intented role and performed very well. The plane wasnt really needed but it could have been a ripper!

 

[red admiral]

Here is a quote from the early trials of the Martin-Baker MB.5 in 1944;

"Greensted[test pilot] however remembered very clearly his first flight in the MB5, and he recalled ; "Right from the very beginning I suppose you could say that it was a badly designed aircraft because it didn't work in the sense that it was directionally unstable. It was an absolute swine to fly because it wouldn't keep itself straight."..."I still don't understand why the thing wasn't right when I first flew it. After all, the theory of design of aircraft at that stage was pretty advanced and I don't understand how he could make a mistake about the directional stability..."

Hardly praise of the MB.5

The Heinkel He 100 was too late to compete with the Bf 109. Even the He 112 was too late to compete with it in the early versions. Maybe the He 100 could be produced in lieu of the Fw 190, but I'm not sure thats a good swap.

The Lyulka turbojets were a good achievement for the Russians, but were very large and very heavy. The RD-1 having a 1:1 thrust:weight ratio. The later TR-1 was better, with 1300kg thrust from 885kg weight, but a bit late, first running in 1944.

 

[kool kitty89]

Totally agree that the MB.5 was no good.

The Whirlwind may have been a bit unnecessary, but considder this: if they'd redesigned it to use Merlins very early on (in the prototype stage) which is plausible seeing the lack of Peregrines, it could have been available much sooner and in larger numbers with better performance. It also could easily have been developed into a capable long-range fighter with an increased fuel capacity and plumbing for drop tanks on it's wng racks. This could have allowd Bomber command to perform sucessful daylight precision bombing to be performed instead of switching to night bombing. Also it could have made long range fighter sweeps into Germany and perform long range recon similar to the Mossie, but earlier on. Considder that the early (single stage) Merlins weighed about 200 lbs more than a Peregrine each and increase with other changes adds another 800 lbs loaded. So 1000 lbs heavier, but with 1,280 hp in place of ~880 hp. With loaded weight going from ~10,300 to ~11,500 lbs power/weight would still go from a decent .17 hp/lb to an amazing .22+ hp/lb! And with much better altitude performance.



The He 112 was a complex mess of parts and compound curves and was outperformed by the 109. The He 100 was a bit late but much easier to produce. It should not replace the 190 though IMO. If posible the He 100 would replace the 109 as the standard fighter (once there were enough) with the 190 still as a heavy interceptor and multi-role fighter. But the He 100 really wouldn't have helped alot over the 109 either. It was fast and fuel efficient due to the sleek lines, which would be important with the fuel limitations. However, it's only practical if it can be produced in a similar manner as the 109.

THe Fw 187 would have been a better interceptor though. In single seat configuration. It would have similar multi-role capabillities as the 190, but with better performance (especially at altitude) in all except roll. It was around early enough to be developed on the same time scale as the Bf 109 was.

With the Fw 187 and Ju 88 there would be no need for the Bf 110 either, both being more capable in all the useful aspects of the 110. (the 187 being too narrow to carry proper radar, but could do everything else and didn't have use for or ability to carry a gunner, the Ju 88 was a competent Nightfighter and multirole craft as well)


Other than production of the Bf 109, Messersmitt could put more focus on its advanced projects like the Me 262 earlier on. And not focus on further developments of the 209-II, 309, 109Z etc.


It would have been better to focus on developing unguided interceptor rockets (R4M) earlier on than waste things on things like SAM's. Work on proximity fuze, improoved radar, lead gunsights, and improoved guns would be more important.

As for the jet engines, all work should have focused primarily on class-I designs and maybe some class-II designs once the class-I's were well established. (the HeS-30/006 and HeS-8/001 shouldn't have been cancelled)

Jets were not a waste of reasourses IMO, it it had been handeled better, even moreso. One major thing to considder is that German jets ran on J2 (bascicly diesel fuel) wihich was in ample supply even at the war's end. (albit with the no way to distribute it with the German transportation system bombed to hell)

 

[Denniss]

@ Denniss

your statement about the DB 601A isn't accurate.

The DB 600 without fuel injection had an output performance of 990 PS, the DB 601A with fuel injection had an output performance of 1100 PS and the DB 601N had an output performance of 1300 PS.

We have calculated the Vmax of the evolution FW 187 1943 as a high altitude fighter with evolution air cooler and optimized for high altitudes.
The best outputperformance (Volldruckhöhe) of the DB 605 was 7200m for the ME 109G, so the 725km/h Vmax was a realistic value.

You should check your sources, no Bf 109G speed graph shows 7500m as having max speed, they always have max speed in the area of 6400 to 6700m. Volldruckhöhe (static) for the 605A was 5700m, with RAM effect at about 6200m.

The DB601A/Aa take-off power is as I gave you - the 1-minute rating was only intended for take-off and even blocked in the Bf 109. Most DB601A-1 power graphs have the 1-min line topping at about 1.5 km with 1150PS, the 601Aa tops at ~1250PS at 1km. The DB 601N had 1175 PS take-off power (5-min rating) topping out at ~1260 PS at just above 2.1km, this 5-min rating was blocked in most DB 601N engines below Volldruckhöhe. There's no serious graph providing 1300PS for the 601N or are you mixing it with the 1350PS DB601E?

 

[delcyros]

You should check your sources, no Bf 109G speed graph shows 7500m as having max speed, they always have max speed in the area of 6400 to 6700m. Volldruckhöhe (static) for the 605A was 5700m, with RAM effect at about 6200m.

Dennis, it appears that both, the DB 605AS and ASM do have a rated altitude of 7.800m and the DB-605D2 has even 8000m rated altitude. The DB-605AS/ASM was extensively used in late Bf-109G5/G6 and Bf-109G14. Check the following link:

The Luftwaffe page , Daimler-Benz DB 605

best regards,
delc

 

[kool kitty89]

Delcyros,

Now that you're on here, what do you think of the mounting of HeS-6 engines on the He 280 with altered wings in a Gloster Meteor style mid-wing mounting? Obviously not the most efficient layout, but it could have made a good intrim measure as the HeS-6 wasn't too much heavier than the HeS-8 and produced thrust in late '39 that the HeS-8 wasn't making until 1941.

And how about using HeS-3's (in standard mounting) for the initial testing of the 280, as the airframe was ready nearly a year before the HeS-8 was and at that time the HeS-8 was making the HeS-3's thrust. The HeS-3 was only modestly greater in diameter (~6 in or 15 cm) Certainly better than glider tests and the leaking HeS-8 prototypes couldn't use cowling and thus added alot of drag.

 

[Denniss]

Dennis, it appears that both, the DB 605AS and ASM do have a rated altitude of 7.800m and the DB-605D2 has even 8000m rated altitude. The DB-605AS/ASM was extensively used in late Bf-109G5/G6 and Bf-109G14. Check the following link:
best regards,
delc

I'm fully aware of the AS and D variants but as they were not specifically mentioned I assumed DonL talked about the standard 605A.

 

[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]

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]

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]

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]

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.