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So basically, they were competitors in making small engines, not big ones for military applications?A few things need to be put into context. . . . for instance "Continental Motors, Inc., Lycoming's main rival in the general aviation engine market" is both true and very misleading to modern readers.
I didn't know about the late payments: Was this absentmindedness or limited funding?Continental was acting like a job shop for the Army, they built parts and ran single cylinder engine tests for the Army when the Army told them to. They were putting little or no money or effort into the engine unless the Army paid them to. And the Army was often late in paying.
I'm amazed they didn't just drop the Continental design or put it on back burner.For the Lycoming "In 1936, the single-cylinder development tests exceeded expectations, passing its 50-hour test requirement. The full-size engine was ready for testing in 1937, and was rated at 1,000 hp"
I'm amazed they didn't just drop the Continental design or put it on back burner.
Call it "medium" sized engines for 4-5 seat aircraft or for small multi engine airliners.So basically, they were competitors in making small engines, not big ones for military applications?
I didn't know about the late payments: Was this absentmindedness or limited funding?
The Continental was the Army;s "baby". Their engineering dept had the most input into it's design and the most ego and career "points" tied up in it.I'm amazed they didn't just drop the Continental design or put it on back burner.
The only reason that the Lycoming's design wasn't designed by the US Army was because Continental apparently wasn't willing to design the engine to a specification that the US Army gave them, so they designed everything themselves, and had Continental build it.The Continental was the Army's baby. The Lycoming was not.
GotchaShortround6 said:Limited funding, please remember that by the Spring of 1939 the army owed Allison over $900,000 for work already done.
No, Continental was building everything the Army told them to build. They just weren't willing to put any of their own money in the project.
The Army was doing the designing but had no manufacturing or machine shop facilities and in the early 30s a limited ability to test engines. So they contracted those parts of the program out. The Army also change the "specification" every few years in the early 30s. Making Continentals reluctance to put any of their own money into it even more understandable.
The Army decided on the cylinder bore and stroke, (and changed it at least once and maybe twice) the Army decided on the type of construction (separate cylinder), the army decided on the number of valves per cylinder and so on.
So, the Army considered it theirs because it was designed exactly as they told them to?No, Continental was building everything the Army told them to build. They just weren't willing to put any of their own money in the project.
I could imagine thatThe Army was doing the designing but had no manufacturing or machine shop facilities and in the early 30s a limited ability to test engines. So they contracted those parts of the program out. The Army also change the "specification" every few years in the early 30s. Making Continentals reluctance to put any of their own money into it even more understandable.
And the reason they designed each cylinder individually was because they didn't think the other way would work?The Army decided on the cylinder bore and stroke, (and changed it at least once and maybe twice) the Army decided on the type of construction (separate cylinder), the army decided on the number of valves per cylinder and so on.
Was the Lycoming O-1230 designed this way because of the USAAC's request for a flat engine? Or did they prefer a flat engine? I'm just curious based on the time-table, and I'm not sure when they were told to make a flat engine.
And the reason they designed each cylinder individually was because they didn't think the other way would work?
Wait, there were actual contractors which wanted this? I thought it was just the USAAC. I'm curious which manufacturers (if I had to guess, Northrop/Douglas -- Northrop loved flying wings, and Douglas had owned Northrop for some period, and Martin -- the XB-16).The Army/Airframe manufacturers were after a flat engine.
So the engine was entirely built around a very specific cylinder design?It's because that was the hyper cylinder arrangement.
Wait, there were actual contractors which wanted this? I thought it was just the USAAC. I'm curious which manufacturers (if I had to guess, Northrop/Douglas -- Northrop loved flying wings, and Douglas had owned Northrop for some period, and Martin -- the XB-16).
So the engine was entirely built around a very specific cylinder design?
There's also the possibility that they get ideas from what the USAAC is developing.There is a little bit of the chicken and the egg thing going on, If the army wants buried engines do the airframe makers tell them no? Or do they make what the army seems to want?
The Burnelli aircraft. What was the opinion of them at the time?There were all kinds of theories as to what efficient aircraft should look like in the 30s. including
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This whole thing was an experiment right? Why didn't they work with NACA to design the cylinder; then distribute the literature to the rest of the engine manufacturers? I figure that this would improve the knowledge base in the United States engine industry.Yes.
Sodium cooled poppet valves, high octane gas, and higher degree of supercharging?The British engineer Harry Ricardo was one of the foremost experts on internal combustion engines right after WW I and in 1927 he published a paper stating the conventional poppet valve engines had fundamental problems and would never exceed 1500hp among other things. He turned out to be wrong about this for a number of reasons that didn't exist when he wrote the paper.
Ironically, they proved right there, that the premise that Ricardo made was wrong.He claimed that the poppet valve had reached it's peak of development and such engines were limited in specific output as in power per cubic in of displacement. For some reason this was like waving a red flag in front of a bull to the US Army engineers and in 1930 they started a series of experiments at Wright field to prove this wrong. They were very fortunate to have S.D. Heron in their employment at the time. and a one cylinder test rig soon exceeded the limit/s claimed by Ricardo.
Wait, two years went by between when they produced a workable cylinder and radiator, and when they contracted the contractor?The Army does not enter into an agreement with Continental until 1932.
Most fighter aircraft had single-engines, and that was already an odd idea unless you had a pusher-prop. I'm not sure what the general idea was on pusher props, and if they realized that you'd be rendering bail-outs impossible.By this time fighter wings were way too thin to take an opposed engine and even bomber wings were looking iffy.
Wait, I thought three or four valves worked better?Another defining characteristic of the "hyper cylinder" was 2 valves in a hemispherical chamber.
This whole thing was an experiment right? Why didn't they work with NACA to design the cylinder; then distribute the literature to the rest of the engine manufacturers? I figure that this would improve the knowledge base in the United States engine industry.
Ironically, they proved right there, that the premise that Ricardo made was wrong.
Wait, two years went by between when they produced a workable cylinder and radiator, and when they contracted the contractor?
Wait, I thought three or four valves worked better?
I thought they did some research with engines...Because NACA (National Advisory Committee for Aeronautics) were aerodynamicists, not engine designers.
Wait a second, didn't Pratt & Whitney and Wright have some inline engines?Sam Heron worked for the Engineering Division of US Army Materiel Command. He designed and developed the hyper cylinder. I'm not sure how widely the information was distributed, but it did not apply to the air-cooled engines of Wright and Pratt & Whitney and was too late, probably, to influence the Allison V-1710, which had began development in 1928/1929.
How much time would have been shaved off the design if they simply continued with a V-cylinder?Harry Ricardo published his paper in 1927 and the USAAC began their experiments in 1930. So, no two years did not go by between the USAAC developing a working cylinder and letting a contract to Continental.
I thought they did some research with engines...
Wait a second, didn't Pratt & Whitney and Wright have some inline engines?
How much time would have been shaved off the design if they simply continued with a V-cylinder?
That's a surprisePossibly, but I am unsure that they did.
Why didn't that design get built? Was there something wrong with it, or it just wasn't ready in time?Well, yes.
The Pratt & Whitney X-1800 was inspired by the Napier Sabre. The X-1800 and XH-2600 are the same engine, and it came first.
That I never knew, but it does seem to indicate that the literature was spread throughout the contractors to some extent...The Wright R-2160 had similar cylinders to the "hyper" cylinder, in that they were 2 valves per cylinder OHC, but they were smaller and based on their air cooled cylinder.
Wouldn't the USAAC have had to avoid re-drawing everything? I figure that would have saved some time -- not sure how much, but...Since Continental did not build a full flat 12, instead starting with the IV-1430 in 1938, I'd suggest no time would have been saved.
Didn't know that...For the time before they built the IV-1430, Continental were testing the cylinder, which could work in a flat or vee engine.