He-119 Coupled Engines

[davebender]

Heinkel He 119 - Wikipedia, the free encyclopedia

Design was begun in the late summer of 1936. A notable feature of the aircraft was the streamlined fuselage, with an extensively glazed cockpit, heavily framed with many diagonal braced windows positioned in the nose, immediately behind the propeller spinner. Two of the three man crew sat on either side of the driveshaft that was linked to a coupled "power system" pair of Daimler-Benz DB 601 engines, forming a drive unit known as the DB 606
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The four remaining prototypes were completed during the spring and early summer of 1938

Heinkel had extensive experience with coupled engines during 1936 to 1938. So why did they have so much trouble getting the arrangemet to work properly on the He-177 bomber?

 

[riacrato]

I don't think enough data is available to rule out the He 119 wouldn't have run into the same problems as the He 177.

 

[davebender]

I don't think enough data is available to rule out the He 119 wouldn't have run into the same problems as the He 177.

I agree. However if coupled engine development began during 1936 (i.e. as soon as the DB600 was certified for production) then Heinkel had 3 years R&D experience with the system before the He-177 prototype first flight. That's long enough to accumulate a considerable amount of test data.

Personally I still prefer the Dornier tandem engine approach for a zerstorer. But Heinkel might have followed up the He-119 with a zerstorer design of their own using coupled engines.

The Me-110 appears to have been a dead end design with a max speed of about 350 mph. The Me-210 had all sorts of development problems. That should have left RLM open to alternate ideas for a follow-on zerstorer.

 

[Shortround6]

The Me-110 appears to have been a dead end design with a max speed of about 350 mph. The Me-210 had all sorts of development problems. That should have left RLM open to alternate ideas for a follow-on zerstorer.

The problems with the 210 weren't known until it was test flown, the Arado 240 also had a number of problems.
These were conventional twin engine planes. Unconventional aircraft, while not necessarily worse, would have posed and even bigger risk. This would have meant continuing development of the conventional aircraft (or a new design of conventional type) as back up. Given the usual 1-2 year delay between concept and flying prototype timing of a 110 replacement (or even substitute) might be little tricky.

 

[davebender]

Tandem engines were "conventional" for Dornier. So something like the Do-335 presents no special development risks as long as it's a Dornier design.

I agree that coupled engines were unconventional (for everyone). So were jet engines. Yet lots of money was poured into both projects.

 

[Shortround6]

Tandem engines were "conventional" for Dornier. So something like the Do-335 presents no special development risks as long as it's a Dornier design.

I agree that coupled engines were unconventional (for everyone). So were jet engines. Yet lots of money was poured into both projects.

Tandem engines in a nacelle, either over wing or under wing or between wings were conventional for quite few people besides Dornier, see a number of French planes or see the Handley Page V/1500 among others.

tandem engines with one propeller at the nose and another behind the tail surfaces were not quite the same thing.

 

[krieghund]

THE ENGINE INSTALLATION IN THE HE177 WAS THE PROBLEM NOT THE ENGINE

THE INSTALLATION IN THE HE119 WAS DIFFERENT FOR THE DB606 AND THE AIRCRAFT WAS KEPT IN SERVICE AS A TEST BED FOR THE DB610 AND DB613

IT GAVE NO ENGINE RELATED TROUBLES

 

[davebender]

THE ENGINE INSTALLATION IN THE HE177 WAS THE PROBLEM NOT THE ENGINE

THE INSTALLATION IN THE HE119 WAS DIFFERENT FOR THE DB606 AND THE AIRCRAFT WAS KEPT IN SERVICE AS A TEST BED FOR THE DB610 AND DB613

IT GAVE NO ENGINE RELATED TROUBLES

Which brings us back to my original question. If Heinkel had the coupled engine working just fine in the He-119 then why did it take so long to make it work properly in the He-177? Heinkel already knew what sort of engine mount, cooling system and shrouding arrangement would work.

 

[krieghund]

The reason is called the RLM...they had to open their shirt buttons to see cause they had their heads fully inserted..(lucky for us eh!)

I have worked in several air force's HQs and I can tell you with first hand knowledge how stuff can go pear shaped really fast especially where hard headed personalities control the subjects and you can't tell them they are wrong.

 

[davebender]

I have worked in several air force's HQs and I can tell you with first hand knowledge how stuff can go pear shaped really fast especially where hard headed personalities control the subjects and you can't tell them they are wrong.

I served in the USN during 1979 to 1985. I served in the U.S. Army during 1986 to 1999 (when I retired). I had my share of HQ problems too. I was counting on new guys like you to fix all the problems that I couldn't during my 20 years of service!

 

[Shortround6]

Part of the problem may have been that while the engines in the 119 used the same gearbox and spacing as the 177 the actual space available for the entire installation may have been some what larger in the He 119.

With the idea of reducing drag the cowl/nacelles of the HE 177 might have been a little restrictive and forced the too close placement of fuel/oil lines and exhaust.

Just speculating but a successful application of an engine in one installation does not always mean a successful installation in a second application.

 

[davebender]

successful application of an engine in one installation does not always mean a successful installation in a second application.

I agree. However knowing what will work in the He-119 should make it a lot easer to make the same engines work in a different airframe.

 

[krieghund]

Ditto