P.59 project not cancelled in 1940 (Do335)

[phylo_roadking]

These next pics are BIG....so I'll just post the links to them; as you can see - open under-fuselage doors...

http://www.airpages.ru/mt/do335_57.jpg
http://www.airpages.ru/mt/do335_56.jpg

...as well as the undercarriage doors - but as we've just seen, the space ABOVE these had to be used for extra tankage! ....

Although theoretically -

All Do-335, except the A-4 and B-1, could also be used a fighter bombers. They each had a bomb bay and they could carry one 500 Kg. bomb or two 250 Kg. bombs. A Revi C-12D gunsight was installed.

..when they weren't carrying a tank in there!

THAT means the Do 335 had 1,100 lbs (500kg) internal bombload vs the Ju 88's 3,100lbs internally!

In other words - the Junkers' internal load was nearly three times larger than the 335's

I wonder how much carrying that internally in place of the auxiliary tank would have compromised the 335's range by, however...?

(To me - it looks like the "racks under the fuselage" were a compromise-on-a-compromise once the tankage was fitted!)

[BDV]

But that means that the 210, the "uber-110" is cancelled. Why would Germany/Luftwaffe do that in favor of a completely untested and futuristic design?

[stg 44]

But that means that the 210, the "uber-110" is cancelled. Why would Germany/Luftwaffe do that in favor of a completely untested and futuristic design?

Because by 1940-2 it was still a failed design. Probably its more likely that they would keep both projects going to see which would be ready first. The Do335, going by the OTL version of development, could be ready by 1943 for operations, as the prototype was first flown in late 1943 and was getting into production and training program development by April-May 1945. So that's about 18-20 months. The fighter version started in June-July to be designed, was ready by the end of 1943 for testing, and got into production in 1945 under serious production problems that probably delayed a 1944 production introduction date, as the bombing of industry in 1944 seriously delayed the design getting it components according to the posts of phylo_roadking.

So without those problems in 1940-42 it could get into production in late 1942-early 1943 and be combat operational in 1943. Design still needed to be worked out in 1940, so the first version would likely be a bomber until testing in 1941 revealed its potential for fighter adaptation. That gets us a fighter prototype in 1942 probably, though work on the bomber version probably yields important development data for the fighter version. By the end of 1942 or in the first half of 1943 it would be production ready, though by that time the Me410 would be ready and with several hundred Me210 airframes built and easily adaptable to the Me410, that would probably become operational first as a stop-gap for the Do335 fighter, which would supersede the Me410 when it is ready in the second half of 1943 for operations. Of course this is optimistic, so perhaps the Do335 won't be combat ready until early 1944...

[phylo_roadking]

Indeed - because here's one of the awkward things with this particular POD...

Because by 1940-2 it was still a failed design.

No - by 1940 it was.

What if the P.59 project had not been cancelled in 1940 and was designed around the pull-push layout that powered the Do335?

It wasn't the ONLY project cancelled then; this was one of a raft of cancellations made in 1940 when the Heerswaffenampt reviewed ALL ongoing projects and dropped the VAST majority of those that couldn't come to fruition within the next year

Like it or not - Projekt P.59 wasn't far enough advanced in 1940 to pass that assessment. Historically - it's very hard to get past that mega-chokepoint. The P.59 project itself would have had to be FAR further forward than OTL...and German aviation just hadn't progressed that far in time.

Probably its more likely that they would keep both projects going to see which would be ready first.

Only in a very very few cases did they do that in 1940; the prototype 210 had been flying (badly) for some time before the assessment.

There are very few times in the history of WWI where What-Ifs come up against a major barrier - but this is one; another would be, for instance, the similar BRITISH review in the summer of 1940 at the start of the so-called "Emergency production" period(s) after Dunkirk - when all work EXCEPT those that would come to fruition within a year...were abandoned, IIRC the Churchill tank being the only exception.

In effect - the problem with the Do 335 wasn't how fast work could have progressed AFTER 1940...it was how far it HADN'T progressed BEFORE 1940!

[stg 44]

That is a hard objection to overcome. I have no answer for you, as you are right, but I was interested in exploring the What If, even though it is virtually impossible from a bureaucratic standpoint.

[phylo_roadking]

What-iffery is fun - but just sometimes it does run up against something, a HISTORICAL " something", that even stopped the designers and dreamers in their tracks...

OR DID IT???



Look at the Wiki article again -

In 1939, Dornier was busy working on the P.59 high-speed bomber project, which featured the tandem engine layout. In 1940, he commissioned a test aircraft, closely modeled on the airframe of the early versions of the Dornier Do 17 bomber but only 40% of the size of the larger bomber, and fitted with a retractable tricycle landing gear to validate his concept for turning the rear pusher propeller with an engine located far away from it and using a long driveshaft. This aircraft, the Göppingen Gö 9 showed no unforeseen difficulties with this arrangement, but work on the P.59 was stopped in early 1940 when Hermann Göring[citation needed] ordered the cancellation of all projects which would not be completed within a year or so.

But this is NOT the full story! Look at the Göppingen Gö 9 article!!!

In 1937, Claudius Dornier observed that adding extra engines and propellers to an aircraft in an attempt to increase speed would also attract a penalty of greater drag. He reasoned that this penalty could be minimized by mounting a second propeller at the rear of an aircraft. In order to prevent tail-heaviness, however, the engine would need to be mounted far ahead of it. Dornier patented this idea and commissioned a test plane to evaluate it.

The aircraft was designed by Dr Ulrich Hütter as a 40% sized, scaled-down version of the Dornier Do 17's fuselage and wing panels, and built by Schempp-Hirth. The airframe was entirely of wood, used a retractable tricycle landing gear (one of the earliest German airframe designs to use such an arrangement) with power supplied by a Hirth HM 60 inverted, air-cooled inline four-cylinder engine mounted within the fuselage near the wings. Other than the engine installation, the only other unusual feature of the aircraft was its all-new, full four-surface cruciform tail, which included a large ventral fin/rudder unit of equal area to the dorsal surface. This fin incorporated a small supplementary tailwheel protruding from the ventral fin's lower tip that assisted in keeping the rear-mounted propeller away from the ground during take-off and landing. The Gö 9 carried the civil registration D-EBYW.

Initially towed aloft, flight tests began in June 1941...

They went on with the project privately!!!

...but later flights operated under its own power. The design validated Dornier's ideas, and he went ahead with his original plan to build a high-performance aircraft with propellers at the front and rear, producing the Dornier Do 335.

It looks like only Heerswaffenampt FUNDING was perhaps halted!

So here's the rub...

1937 to 1941+ is five years; before Dornier could go ahead with the Do 335 "Projekt P.231" there was FIVE YEARS of design work, testing and concept testing

I wouldn't like to guess how much design time WASN'T actually lost by the simple withdrawal of government funding! That being the case - COULD work on the historical P.231/Do335 have progressed any faster than OTL??? Claude Dornier was making pots of dosh from his aircraft factories, he could fund his own design work and concept testing! And obviously DID....

I don't think your particular POD is going to buy back as much time ATL for the DO 335 entering service as you think....

[phylo_roadking]

As a P.S....

Earlier you asked about the effects of the nightfighter conversion; I found THIS -

Next in line of the Pfeil variants was the Do 335A-6 (prototype Do 335 V10), which was the night fighter variant. Armament remained unchanged from the fighter bomber, but FuG 220 Lichtenstein SN-2 or Fug 217J Neptune/FuG 218 Neptun V airborne intercept radar was to have been incorporated, the aerials being located forward of the wing (lateral beam port and vertical beam starboard). To operate the radar a second crewman was needed, and to accommodate him a cockpit was incorporated above and behind the pilot. Giving the Pfeil an even stranger appearance than before, the second cockpit also meant a considerable restructuring of the fuel system since fuel capacity was reduced to 600 litres. To augment this the weapons bay area was converted over to fuel storage.

...but the NEXT part of that paragraph is very interesting -

The negative effect on performance of the extra cockpit, aerials, weight and other modifications such as flame damping tubes over the exhaust ports was in the region of 10 percent, but production aircraft would have offset this partially by being fitted with DB 603E engines with MW-50 (water/methanol) boost instead of the DB 603A retained by the sole example. Production was scheduled to have been undertaken by Heinkel in Vienna, but this plan was overtaken by events and the tooling was never assembled. There was only one operational Do 335A-6, flown by Werner Baake in I./NJG 3 flying Do 335 V-10 (CP+UK) with FuG 220 Lichtenstein SN-2 radar.

!!!

And so we run up against ANOTHER very necessary POD...!

The 1,750hp DB 603A was developed in 1937 and the 1,800hp DB 603E in 1939.

The two stage supercharged high altitude DB 603G first made an appearance on the He-309 prototype in July 1942 as the DB 603EB which would have been a development prototype.

Prototype Fw-190 V-32 was provided to Daimler Benz for testing with the DB 603G in late1943.

Production of the DB 603G (aka DB 603EB) apparently ceased in mid 1944, however the engine continued development under various guises with modification upgrades after this, mainly with Methanol-Water kits. These later supercharged versions include the DB 603N (for 100 octane C-3 fuel) and DB 603L (for 87 octane B-4 fuel)

There are indications that late in the autumn 1944, Focke Wulf was intending to switch from use of the Jumo 213 A-1 engine on their Ta-152 Dora D-9, to use of the DB 603 LA on the D-14, or DB 603G for the D-15 Dora.

German engines were limited in how to raise power output by low octane fuels which they had available. Thus unlike the Western Allies who preferred to raise boost pressures the Germans were more absorbed with increasing engine compression. The DB-603 simply increased the power of it's predecessor by reboring and increasing the piston stroke.

Look at the years mentioned in there...

...there's a very major issue with an early availability of the 603E to obviate that power loss on the 335 nightfighter version!

[stg 44]

Okay, thanks for all of the extra info. The one thing I will add to your first post is that even though Dornier continued funding for concept testing in 1940-1 and probably beyond, had he had a project to work toward and government funding to help push the idea forward, the development work could have been put to use earlier than historically happened, but not as early as I suggested. So perhaps a mid-late 1944 availability at the earliest, too late to make that much of a difference.

[phylo_roadking]

the development work could have been put to use earlier than historically happened

Wellllll....

If the Go 9 only flew in mid-1941...any results it yielded from comprehensive flight testing could have taken some time to feed back into Dornier's private work on the P.231 in - say....1942?

And when was the P.231 uptaken again and given the Do 335 serial? 1942.....

I'm not sure Dornier really lost that much time at all!

The point is....this is a new concept; mounting back-to-back engines on the Wal and Dornier Do X is one thing - but converting THAT into the whole stresses on a complete airframe??? The concept would ALWAYS have required a LOT of concept proving and flight testing. I really don't think he could have brought a whole new concept on much ahead of that OTL schedule.

[stg 44]

Uptaken as a bomber. If it were uptaken as a fighter and time not lost designing a bomber, but rather a heavy fighter, that would have saved several months. Those months would have meant less disruption to production resulting from somewhat less damage to industry from the bomber offensive, which historically delayed the Do335 becoming active.

[phylo_roadking]

Uptaken as a bomber. If it were uptaken as a fighter and time not lost designing a bomber, but rather a heavy fighter, that would have saved several months.

I'm not sure there was time to make up; OTL, from the acceptance by the RLM of the project in 1942 to the first V-1 prototype flying was only nine months, after all! Im not sure they could have clawed any more back!

Also - it wasn't a case of bomber OR fighter...it was a fighter/bomber intruder I.E. a Jabo! They all had that small weapons bay - even though as we've seen some of the manufactured aircraft could use it, and others couldn't because of the fuel tank! Only the Do-335 A-4, an unarmed, high speed, photo-recon aircraft and the B-1 aircraft couldn't ideally do both from assembly.

I.E. that's what Dornier designed, a dual-role aircraft. He didn't "loose time" designing one over the other This was no Me 262....

[stg 44]

http://en.wikipedia.org/wiki/Dornier_Do_335#Development

In May 1942, Dornier submitted an updated version with a 1,000 kg (2,200 lb) bombload as the P.231, in response to a requirement for a single seat high-speed bomber/intruder. P.231 was selected as the winner after beating rival designs from Arado, Junkers, and Blohm & Voss development contract was awarded as the Do 335. In autumn 1942, Dornier was told that the Do 335 was no longer required, and instead a multi-role fighter based on the same general layout would be accepted. This delayed the prototype delivery as it was modified for the new role.

Fitted with DB 603A engines delivering 1,750 PS (1,287 kW, 1,726 hp) at takeoff, the Do 335 V1 first prototype, bearing the Stammkennzeichen (factory radio code) of CP+UA, flew on 26 October 1943

Why did the delay then result a then more than 1 year delay? From May-October for building the bomber version, then another year for the fighter version modifications and final construction. Even the He177 prototype took about a year to build and was probably more complex than the Do335.

[phylo_roadking]

Why did the delay then result a then more than 1 year delay? From May-October for building the bomber version, then another year for the fighter version modifications and final construction.

Well, first work has to halt on a bomber only version...after six months wasted! THEN there's a lot of redesign needed - electrical systems, airframe balance factors, different stress factors, etc. etc.

That bit about the V1 aircraft flying nine months aftert being "ordered" was for the new fighter version order...thus nine months FROM October 1942 until it was ready to fly Emphasis there on ready - there would be ground testing, taxiing tests etc. first...

This was a WHOLLY new aircraft, working on new principles etc....with only the small Go 9 concept tester preceeding it. I would assume a VERY rigorous testing regime with no corners cut.

[BDV]

I think it is possible, with some cooperation and goodwill.

In the ideal situation, ItaloGerman cooperation would result in germans adopting the SM79 for antishipping work, leading to cancellation of Do217 (leaving Junkers and Heinkel as the germans bomber production outfits).

A consortium of Messerschmidt and Dornier would then put together their expertise base (Me- inline fighter plane design, Do multiengine bombers) to produce two viable fighter bomber designs for the Reich in the late 1942 timeframe - Me "310D" and Do "335M", so production on both can start in January 1943.


p.s. Is the pushpull concept going to work as well with DB601s, rather than 603s?!? THAT would be a significant shot in the arm!

[phylo_roadking]

A consortium of Messerschmidt and Dornier would then put together their expertise base (Me- inline fighter plane design, Do multiengine bombers

I'm not sure that Messeschmitt's inline fighter design capability matched Dornier's inline-engined aircraft experience...the Do 10, various marks of the the D0 17, the Do 22, the Do 23, the Do 217....in quite a few different configurations

Whereas how many inline engined aircraft did Messerschmitt actually design from scratch - as opposed to teasing many and various marks out of the bf 109 etc.? We COULD of course add the Me 210 and the 410...but they are perhaps more famous for their lack of handling manners than their capabilities?