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I thought Allison was a division of General Motors. A giant in the automotive world.
The fortunes of your giant at the beginning of the 30sI thought Allison was a division of General Motors. A giant in the automotive world.
Someone in the U.S. Army Air Corps must have really like Allison. As soon as examples of the DB601 and RR Merlin were available for comparison I would have cancelled the Allison contract.
A shame that Packard didn't develop their own, higher displacement engine to compete with the V-1710. Not an update of the old V-2500, but a brand new V-2000 with all modern features.Why?
Very early Merlins (MK I) or the ramp head models had to be redone. The mid 30s DB 600 didn't set the world on fire and had a number of teething problems. In addition to it being carburetored and having a single speed (non-variable) supercharger drive.
The US had no other V-12 on offer at anywhere near the state of development. Both the Continental and the Lycoming 12s were far,far from production and the Packard was out of date.
By the time the Merlin MK III is available for testing or a DB 601 as installed in a 109E commitments had already been made.
There are also fundamental differences between some Allison models. A lot of major changes from the C series engines and the E and F series engines.
They certainly had the know-howA shame that Packard didn't develop their own, higher displacement engine to compete with the V-1710. Not an update of the old V-2500, but a brand new V-2000 with all modern features.
Not bad considering it wasn't even the the 30s yetThe Packard 1A-2775 was an X-24 engine.
While it may have used a common cylinder head it continued to use separate cylinders.
also the supercharged version
Perhaps not the engine of choice for a Spitfire/109 competitor, although it might have been the basis for for an early American Typhoon
In the late 30s it may have offered 3 times the power but it also came at the cost of around 3 times the weight.
Why?
Very early Merlins (MK I) or the ramp head models had to be redone. The mid 30s DB 600 didn't set the world on fire and had a number of teething problems. In addition to it being carburetored and having a single speed (non-variable) supercharger drive.
The US had no other V-12 on offer at anywhere near the state of development. Both the Continental and the Lycoming 12s were far,far from production and the Packard was out of date.
By the time the Merlin MK III is available for testing or a DB 601 as installed in a 109E commitments had already been made.
There are also fundamental differences between some Allison models. A lot of major changes from the C series engines and the E and F series engines.
There was nothing fundamentally wrong with the V-1710.
The V-1710 actually compares quite favourably with the Merlin in some areas, such as weight (fractionally), reliability, cost of construction and time between overhauls and ease of maintenance.
Where it loses out is frontal area (slightly), power at altitude (due to poorer supercharger design), specific fuel consumption per hp and ultimate hp development (mostly because Rolls-Royce poured more effort into developing the Merlin than Allison did for the V-1710).
They certainly had the know-how
Their own proprietary powerplant, the 1A-2775, was developing 1,300hp and that was in 1929.
Things seemed to go downhill for US liquid-cooled development around the mid-20s. The Schneider Trophy was won in 1925 by a US liquid-cooled unit, the Curtiss V-1400 - the most advanced powerplant in the world at the time. The Atlantic was then crossed in 1927 by a radial in the form of the Wright J5 Whirlwind. A year later, the Pratt Witney Wasp joined the party.
The pace of the inline was lost behind the durability of the radial and fortunes slid further with the US Navy Bureau of Aeronautics endorsing the use of the radial in all future aircraft programs. That's where the contracts were and that's where the three main US powerplant manufacturers, Curtiss, Pratt Witney and Wright, concentrated their efforts.
Curious, at the end of the 20s, the principal powerplant considered for aeronautical programs was the Pratt Witney Hornet B at 575hp; curious because there were around a dozen liquid-cooled powerplants available that offered more than 575hp, including the afore-mentioned 1A-2775.
I agree.
The problem is the U.S. Army Air Corps was willing to settle for a sub standard (compared to Britain and Germany) supercharger installation. If the U.S. Army Air Corps had insisted on a better supercharger "or else we will purchase RR Merlins from Britain" then it would have happened.
I agreeThere was nothing fundamentally wrong with the V-1710
(mostly because Rolls-Royce poured more effort into developing the Merlin than Allison did for the V-1710).
That was the pivotal yearIf what Shortround says is true, they needed to start saying it pretty early (1938 at the latest) to get it done by Jan 1942.
I agree.
The problem is the U.S. Army Air Corps was willing to settle for a sub standard (compared to Britain and Germany) supercharger installation. If the U.S. Army Air Corps had insisted on a better supercharger "or else we will purchase RR Merlins from Britain" then it would have happened.