US Army Hyper Engine

[kmccutcheon]

The engine was actually rather large. The one test bed aircraft went from this.
to this
View attachment 539869

What is the aircraft and its engine?

 

[Jugman]

The Vultee V-11/ A-19 is probably what he wanted to show a picture of. The YA-19A was just a test bed and I don't think we can draw much of a conclusion from its O-1230 installation.

 

[Shortround6]

Yes, it was test mule, but the engine was about 107 inches long vrs about 86 in for an Allison F series and more importantly for single engine plane, it was 44 in wide vrs about 30 for a Allison or Merlin. Granted that does not include exhausts on the Allison or Merlin but that is a wide engine.

 

[Zipper730]

Apparently, I've found the engine data here: It may have been flat relative to length, but it wasn't all that flat, and boy was it long.

I also have the XI-1430 dimensions here

Engine.....O-1230.....I-1430.....V-1710-111
Weight.....1325 lb.....1615 lb.=1395 lb.
Length.....106.7"....\\112"..=-=86"
Width...=..44.1"-===.30.9=-..\.29.3"
Height...=.37.9".===.33.4.==.-37.6"

 

[Jugman]

Oh, I agree that A flat engine is sub-optimal for a large single engine plane. Like most US liquid-cooled engines of the 30s, the O-1230 had a rather long nose for streamlining. This most certainly could have been shortened a considerable amount. The ~106" of the O-1230 length may include the length of the generator as well.

The dimensions I have for the O-1230 are LxWxH 105.66 x 44.13 x 34.08. The supercharger scroll is probably between 20-24' in diameter. Most all of the engine fits in this envelope. You have the coolant pump on the bottom and the dual magneto, starter, and carburetor on top, that all extend beyond this envelope.

 

[AMCKen]

"I don't think that the RAF, Air Ministry, or whoever, was dictating the engine layout.

The Dagger, Rapier and Sabre all came from one company and one designer. The concept was for the maximum number of cylinders in the smallest space.

Then there was the Fairey P.24, which was a H engine, but essentially two separate engines in one crankcase, each half operating as an opposed 12. That went nowhere.

And there was the Rolls-Royce Eagle 22. Similar in layout to the Sabre.

I'm not familiar with any other H engines."

From my list of H-engines. Some built in low numbers, some maybe not at all - just 'engineering exercises'.
Clerget Transatlantique
Continental XH-2860
Fairey Monarch
Fairey Prince
Jalbert-Loire 16-HJ
Klöckner-Humboldt-Deutz Dz720
Lycoming XH-2470
Menasco XH-4070
Napier Dagger
Napier E112 (enlarged Dagger)
Napier Rapier
Napier Sabre
Packard 1A-3000
Packard 2A-5000
Pratt & Whitney XH-2240
Pratt & Whitney XH-2600
Pratt & Whitney XH-3130
Pratt & Whitney XH-3730
Ranger XH-1850
Reggiane H-24
Rolls-Royce Eagle II
Samara P-065
Studebaker XH-9350
Wright XH-4240

 

[Jugman]

The Wright XH-4240 should be a 24 cylinder hex engine. Basically two H-2120s. Well more like the H-2120 was half a H-4240. The H-4240 was never built.
There was a Merlin derived 16 cylinder H engine study too.

 

[Shortround6]

I believe there were several French engines, a pre-war using Hispano cylinder blocks,

They continued the sales effort post war in a somewhat modified form.

The French also tried to market an H-24 engine using Jumo 213 cylinder blocks.

 

[wuzak]

Argus also built some H-24s.

Argus H-24s

The As 413 was based on Jumo 213 blocks and heads.

 

[johnbr]

There was also the db-h16 and h-24 2000hp and 4000hp. It is said they made one.

 

[wuzak]

Rolls-Royce proposed an H-24 Merlin, basically two Merlin 61s, operating independently, on one crankcase. Like the Fairey P.24.

It wasn't built, but if it was it would have been more powerful and lighter than the Eagle H-24.

A mock-up was built
https://www.strijdbewijs.nl/birds/spitfire/secret/ng73.jpg
https://www.strijdbewijs.nl/birds/spitfire/secret/ng74.jpg

from spitfiles

 

[AMCKen]

The Wright XH-4240 should be a 24 cylinder hex engine. Basically two H-2120s. Well more like the H-2120 was half a H-4240. The H-4240 was never built.
There was a Merlin derived 16 cylinder H engine study too.

I was just going by the 'H' designation on that one. Apparently that mean 'hyper', not the configuration. Thanks.

 

[AMCKen]

BRM and Brough also built 'H' style engines. BRM was a 16 cylinder 2.75" bore, 1.925" stroke 182.9 ci - just under the 3 litre limit. Just about 600hp at 10,500rpm. The Brough 'Golden Dream' motorcycle engine was a 4 cylinder, just under 1000cc. As far as I know.
Fun starts at about 5:20

 

[Zipper730]

Was the Lycoming corporation planning on building a flat-design off the bat, or did they adopt the flat cylinder configuration when the USAAC wanted it to be done?

 

[Zipper730]

From my list of H-engines. Some built in low numbers, some maybe not at all - just 'engineering exercises'.
Clerget Transatlantique
Continental XH-2860
Fairey Monarch
Fairey Prince
Jalbert-Loire 16-HJ
Klöckner-Humboldt-Deutz Dz720
Lycoming XH-2470
Menasco XH-4070
Napier Dagger
Napier E112 (enlarged Dagger)
Napier Rapier
Napier Sabre
Packard 1A-3000
Packard 2A-5000
Pratt & Whitney XH-2240
Pratt & Whitney XH-2600
Pratt & Whitney XH-3130
Pratt & Whitney XH-3730
Ranger XH-1850
Reggiane H-24
Rolls-Royce Eagle II
Samara P-065
Studebaker XH-9350
Wright XH-4240

Frankly we should create an engine page just of all the engine concepts that were up in the air during this period... this is one from Packard btw

StatsAllPackardAero.pdf

 

[wuzak]

Was the Lycoming corporation planning on building a flat-design off the bat, or did they adopt the flat cylinder configuration when the USAAC wanted it to be done?

Built what the Army were asking for.

 

[Shortround6]

Frankly we should create an engine page just of all the engine concepts that were up in the air during this period... this is one from Packard btw

StatsAllPackardAero.pdf

Packard was out of the aircraft engine business for several years during the 1930s. Their chief aeronautical engineer Lionel Woolson was killed in an airplane crash in April 1930, The Navy had decided no more liquid cooled engines and they were Packards biggest customer. The Depression the market for aircraft engines of any type got very tight. At some point in the late 30s Packard tried to get back in the game but most of the late 30s engines were either rehashed versions of the almost 10 year old engines or very large X-24 versions of the old V-12s.
The large V-12 was the basis for the PT-boat engines.

 

[Zipper730]

Built what the Army were asking for.

When did Lycoming join in?

 

[wuzak]

When did Lycoming join in?

You should try google.

In 1932, the engineers at Lycoming Engines became aware that the United States Army Air Corps (USAAC) wanted a high performance engine that could produce at least one horsepower per cubic inch (46 kW/L) of engine displacement and that a contract had been made with Continental Motors, Inc., Lycoming's main rival in the general aviation engine market. Lycoming's management wanted to be considered for development of the next generation engine, but no USAAC development contract was signed. Still determined to become known as a high performance engine manufacturer, Lycoming began an experimental, high-performance engine of its own. After spending US$500,000, and after many attempts to develop a successful engine, it finally came close to the USAAC specifications with the 1,200 hp (895 kW) O-1230 engine.

Lycoming O-1230 - Wikipedia

 

[Zipper730]

You should try google.

I assumed they became aware in 1932, but I didn't know when they signed. It could have been 1932 or 1933. Regardless, it seemed that the decision to go to to a flat cylinder appears to be 1933...