Hyper-Engine of 1930: Allison...AND Packard?

In 1930 the US Army Air Corps initiated a study project known as 'Hyper-Engine' to obtain aircraft engines yielding 1 horsepower per cubic inch at a weight of less than 1 pound per horsepower delivered. Allison actually developed such an engine rather early, the V-1710, that would power the P-38 Lightening and P-51a among others. Suppose Packard was able to replicate or improve on the success of their prototype 5a-2500 engine which delivered 1500 horsepower in a package weighing about 1200 pounds, though the displacement was over 1500 cubic inches. Would this engine have an impact on late interwar airliner, bomber, fighter, or potentially marine engine development, especially if knocked off and incorporated into other projects overseas?

Please note that Packard *was* actually able to build such an engine by 1941 (V-1650), this thread is to assess opinions on outcomes if it could do so a decade earlier.
 
In 1930 the US Army Air Corps initiated a study project known as 'Hyper-Engine' to obtain aircraft engines yielding 1 horsepower per cubic inch at a weight of less than 1 pound per horsepower delivered. Allison actually developed such an engine rather early, the V-1710, that would power the P-38 Lightening and P-51a among others. Suppose Packard was able to replicate or improve on the success of their prototype 5a-2500 engine which delivered 1500 horsepower in a package weighing about 1200 pounds, though the displacement was over 1500 cubic inches. Would this engine have an impact on late interwar airliner, bomber, fighter, or potentially marine engine development, especially if knocked off and incorporated into other projects overseas?

Please note that Packard *was* actually able to build such an engine by 1941 (V-1650), this thread is to assess opinions on outcomes if it could do so a decade earlier.

erm, was'nt the v1650 a merlin in an american dress

its not much of an achievement building someone elses engine is it
 
The Packard V-1650, of course, being the license built Merlin...

(damn, gazumped...)

Looking at the rest of what Packard came up with, it doesn't look like they had a very large design team; they never recaptured the early success of the Liberty, I'd reckon they were probably less effective an engine designer than, say, Fairey or Armstrong- Whitworth.

Look to the larger firms, Wright or Pratt and Whitney, or for that matter Allison whose V-3420 does make the hp/weight mark, but at the cost of being a very large and powerful engine; difficulty to fit into something P-51 or even 47 sized.

Twin engined B-17s seem entirely possible however, and for heavy fighter-bombers, like the pair it was proposed for, maybe- it's a different air war you're looking at there though, and like the Me/Bf- 110, they would probably need escort in themselves.
 
Packard did make 1500 engines beside the 2500 engines, which produced 500 hp. Packard engines didn't set the world on fire, but the marine versions powered some pretty spiffy PT boats. Allison's first sales of the V-1710 went to the navy to power dirigibles, before the P-37 got a turbo-charged powerplant. Later, the much-maligned integral supercharger was incorporated and the rest was history. I've just finished reading that the Mustang designer, Edgar Schmued, thought so highly of Allison that he wouldn't buy a General Motors car. Hank Ford pinned significant hopes on his version of the V-1650, a modern up-to-date version of the Merlin, going as far as making castings and tooling. The USAAC said they didn't need it. Hank chopped 4 cylinders off the casting and made the GAA tank engine. However, the Ford engine, albeit the GAA, did finally make its way into a Mustang. The Ford might have been the engine you're looking for. When the gummint finally got into ordering some hyper engines and some new-fangled aircraft to put them in, every man-Jack of 'em turned out to be a bust. Every one.

KH_Mustang-b.jpg
 
Packard did make 1500 engines beside the 2500 engines, which produced 500 hp. Packard engines didn't set the world on fire, but the marine versions powered some pretty spiffy PT boats.

Marine rated engine were like tank engine, downrated for longevity

The aircraft version the 5A-2500 weighed 1430 pounds, 1750HP@2800rpm

a decade later, the V-1650-1 (Merlin) was 1510 pounds, 1435HP@3000, on higher octane gas.

I don't know why Packard didn't develop that engine more in 1930
 

Driftless

Donor
Marine rated engine were like tank engine, downrated for longevity

The aircraft version the 5A-2500 weighed 1430 pounds, 1750HP@2800rpm

a decade later, the V-1650-1 (Merlin) was 1510 pounds, 1435HP@3000, on higher octane gas.

I don't know why Packard didn't develop that engine more in 1930

Great Depression impact? Packard's bread & butter was luxury cars, and maybe they felt they needed to maintain a narrow focus to ride out the crisis? It does seem like a missed opportunity in hindsight.
 
Marine rated engine were like tank engine, downrated for longevity

The aircraft version the 5A-2500 weighed 1430 pounds, 1750HP@2800rpm

a decade later, the V-1650-1 (Merlin) was 1510 pounds, 1435HP@3000, on higher octane gas.

I don't know why Packard didn't develop that engine more in 1930

I don't know where you got your data, but there's plenty of data on the marine engines which were developed right through the war years. With a supercharger, the 4M engine weighed 2950 lb dry and was rated at 1200 to 1500 hp depending on source, at up to 3000 rpm., on 100 octane. The 5M engine weighed 3100 lb., and was rated at 1500-1850 hp., on perhaps 115/145 octane, equipped with supercharger with intercooler, moved to the back of the engine. Gearing the aero engine added 215 pounds to the dry weight. 175 3A engines were built. One off for the 4A and 5A. For comparison, 14,000 3M, 4M and 5M engines were built, including 4,686 for the British for use in Vosper boats. The engines sucked fuel mercilessly, and were so noisy that a Ford V8 was used for sneaking around, sort of a 6-8 knot stealth trolling motor.

4A-2500 with Capt. Woolson.jpg
 
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I don't know why Packard didn't develop that engine more in 1930
Possibly the 5A- was simply so powerful it was unreliable? That much power of of that light an engine makes me think they were possibly cutting corners.
 
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Possibly the 5A- was simply so powerful it was unreliable? That much power of of that light an engine makes me think they were possibly cutting corners.

Has a bit more displacement than the DB-605, but similar power and lighter.

Also pretty close to the Rolls Royce 'R' series used in seaplane racing

I figure that the Marine engines weighed so much more was from Iron inplace of alloy
 
Marine rated engine were like tank engine, downrated for longevity

The aircraft version the 5A-2500 weighed 1430 pounds, 1750HP@2800rpm

a decade later, the V-1650-1 (Merlin) was 1510 pounds, 1435HP@3000, on higher octane gas.

I don't know why Packard didn't develop that engine more in 1930

The 5A was a one off Experimental engine - it wasnt unheard of for Engines of this period to produce very high output.

The Rolls Royce R engines used in the Super-marine S6 and S6B Schneider Trophy winners in 1929 and 1931 - it was a 1640 pound 2800 HP engine

However neither it or the 5A-2500 or other 'sporting engines' of the period would have been useful at the time for Military or civilian use.

Their operational life time would have been measured in 10s of hours between rebuilds at best.
 
The 5A-2500 was an experimental engine, presumably direct drive, which was tested and not continued with. Was the power rating ever achieved, and if so, when, and for how long? That's what we don't know. Do you wish to assume it was successful, but Packard just packed it in just because they had enough success already?

That list of engines also cites a number of X, W and H-type engines with hp figures up to 3500. Nothing came of them either.
 
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And a decade earlier, so the -605 had much better alloys.

A lot of those things broke after literately minutes.

I don't think alloys changed all that much, vs manufacturing techniques.

Some did break. But used a witch's brew of fuel that gave about a thousand HP more than the 5A when they did work for the Schneider Trophy races
 
The 5A-2500 was an experimental engine, presumably direct drive, which was tested and not continued with. Was the power rating ever achieved, and if so, when, and for how long? That's what we don't know. Do you wish to assume it was successful, but Packard just packed it in just because they had enough success already?

Don't know: not found much on the 'net about it.

But probably would have made a good competition to the Allison, having 30% more displacement.

Aero Engines of similar displacement did find success, like the DB-605 and AM-38
 
More engines failed than succeeded, and the Packard story remains untold and unfulfilled. The Ford story is also a dead end. 1800 hp on a dyno test, with direct injection and turbosupercharger, and then nothing. No story, no plausible WI. No facts, because nothing happened. All the hyper engines spawned by Proposal R40C came to nothing, including the Chrysler that powered the fastest-looking slow Thunderbolt. The only hyper engine that amounted to something was the Napier Sabre, which still failed to achieve its proposed goals, unless you reduce those goals. It took a lot of effort and "priority", taking from the rest of the industry, and, in the end, was replaced by a common Bristol Centaurus which, although of much greater displacement, was in a similar weight class, and could also receive post-war commercial success.
 
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