Fairey aero engines - any good info?
- Thread starter tomo pauk
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Shortround6
Major General
There seem to have been two Prince engines. A V-12 with 5.25in X 6.0in Cylinders (1559cu in) and the later H-16, also with 5.25in X 6.0 in cylinders (2078cu in). It was vertical in lay out and was virtually two eight cylinder opposed engines, each driving one propeller of a co-axial counter rotating propeller. 1540hp for take-off at 2800rpm and 3lbs boost (?) weight may have been 2180lbs (?)
The Monarch was a 24 cylinder version of the H-16 Prince, same size cylinders ( 3117 cu in) and same drive arrangement to the propellers, there is a photo of the Battle test bed with just one propeller turning, each halve of the engine could be run independently. One description says a 4 speed, two stage supercharger which seems very unlikely. The Prince used a 2 speed single stage and what is more likely for the Monarch is TWO separate two speed single stage superchargers, one for each halve of the engine. Power is given as 2240hp for take off at 3000rpm no manifold pressure given and no weight listed.
The Monarch was a 24 cylinder version of the H-16 Prince, same size cylinders ( 3117 cu in) and same drive arrangement to the propellers, there is a photo of the Battle test bed with just one propeller turning, each halve of the engine could be run independently. One description says a 4 speed, two stage supercharger which seems very unlikely. The Prince used a 2 speed single stage and what is more likely for the Monarch is TWO separate two speed single stage superchargers, one for each halve of the engine. Power is given as 2240hp for take off at 3000rpm no manifold pressure given and no weight listed.
Hi Tomo,
The following is from Alec Lumsden's British Piston Aero Engines and their aircraft (ISBN1 85310 294 6):
Fairey V-12 Prince I, 650/670 hp and Super Prince II, 720 hp, 12 cylinder upright 60 degree Vee shaped, poppet valve, water cooled engine. It was built in two versions, unsupercharged and fully supercharged, but exact details are few. Its propeller drive was spur geared, RH tractor drive. Bore/stroke 5.25 x 6.0 in Vol 1,558.62 cu in, 25.54 litre. The fully supercharged version designated V-12S, Prince II (or probably Super Prince was intended to develop 720 hp at 2,500 rpm at 12,000 ft for a modest dry weight of 1,150 lb. Aircraft: Fairey Fox II (probably the Prince I but uncertain.)
Fairey H-16S Prince 3, 1,540 hp (1939) 16-cylinder "double' engine in-line vertically opposed H shaped, poppet valve, liquid cooled. Bore/stroke 5.25 x 6.0 in (133.35 x 152.4 mm), vol. 2.078 cu in, 34.05 litre. Two speed single-stage supercharged. Effectively two independent engines driving co-axial counter rotating LH/RH propellers. Aircraft: Fairey Battle I
Fairey P-24 Monarch, (1939), 2,240 hp, a more powerful development of the Prince H-16 with greater capacity. 24-cylinder 'double' engine, in-line vertically opposed monobloc castings, H-shaped, poppet valve, liquid cooled. Bore/stroke 5.25 x 6.0 in (133.35 x 152.4 mm), vol. 3,117 cu in, 51.08 litre. Compression ratio 6:1. Four speed, two stage supercharged. Geared, spur .543:1. Independently controlled and synchronised, co-axial counter rotating and feathering LH (front), RH (rear) propeller drives. Length 86.25 in; width 43.0 in height 52.5 in. Aircraft Fairey Battle I
Some text from the introduction to Fairey engines on these types:
The first real Fairey engine was designed in considerable secrecy. It was intended to be directly competitive with RR's highly supercharged P.V.12 (later named Merlin). It was designated the Fairey P.12 and given the name Prince. This was built and run in two versions, labelled according to the degree of supercharging... By the end of 1934, three engines had completed 550 hoursof bench running, including ten hours at 420 hp and three hours at 700 hp. One Prince was flown in Belgian Fairey Fox II.
I hope this is of interest to you. I'll post some more tomorrow on the H-16 Prince and the Monarch.
The following is from Alec Lumsden's British Piston Aero Engines and their aircraft (ISBN1 85310 294 6):
Fairey V-12 Prince I, 650/670 hp and Super Prince II, 720 hp, 12 cylinder upright 60 degree Vee shaped, poppet valve, water cooled engine. It was built in two versions, unsupercharged and fully supercharged, but exact details are few. Its propeller drive was spur geared, RH tractor drive. Bore/stroke 5.25 x 6.0 in Vol 1,558.62 cu in, 25.54 litre. The fully supercharged version designated V-12S, Prince II (or probably Super Prince was intended to develop 720 hp at 2,500 rpm at 12,000 ft for a modest dry weight of 1,150 lb. Aircraft: Fairey Fox II (probably the Prince I but uncertain.)
Fairey H-16S Prince 3, 1,540 hp (1939) 16-cylinder "double' engine in-line vertically opposed H shaped, poppet valve, liquid cooled. Bore/stroke 5.25 x 6.0 in (133.35 x 152.4 mm), vol. 2.078 cu in, 34.05 litre. Two speed single-stage supercharged. Effectively two independent engines driving co-axial counter rotating LH/RH propellers. Aircraft: Fairey Battle I
Fairey P-24 Monarch, (1939), 2,240 hp, a more powerful development of the Prince H-16 with greater capacity. 24-cylinder 'double' engine, in-line vertically opposed monobloc castings, H-shaped, poppet valve, liquid cooled. Bore/stroke 5.25 x 6.0 in (133.35 x 152.4 mm), vol. 3,117 cu in, 51.08 litre. Compression ratio 6:1. Four speed, two stage supercharged. Geared, spur .543:1. Independently controlled and synchronised, co-axial counter rotating and feathering LH (front), RH (rear) propeller drives. Length 86.25 in; width 43.0 in height 52.5 in. Aircraft Fairey Battle I
Some text from the introduction to Fairey engines on these types:
The first real Fairey engine was designed in considerable secrecy. It was intended to be directly competitive with RR's highly supercharged P.V.12 (later named Merlin). It was designated the Fairey P.12 and given the name Prince. This was built and run in two versions, labelled according to the degree of supercharging... By the end of 1934, three engines had completed 550 hoursof bench running, including ten hours at 420 hp and three hours at 700 hp. One Prince was flown in Belgian Fairey Fox II.
I hope this is of interest to you. I'll post some more tomorrow on the H-16 Prince and the Monarch.
- Thread starter
- #4
Thanks for the input, people
I was following the discussion about the Fairey engines at the Great planes forum (many familiar names there ), starting this thread in the intention to learn more about this pieces of engineering.
nuuumannn, I do look forward for any good info.
I was following the discussion about the Fairey engines at the Great planes forum (many familiar names there
), starting this thread in the intention to learn more about this pieces of engineering.nuuumannn, I do look forward for any good info.
wuzak
Captain
As Shortround says, it is unlikely that the P.24 had a 4 speed two stage supercharger. As it was basically two engines on a single crankcase it is most likely that each half had a single stage two speed supercharger.
There also seems to be some dispute about the engine weight. Some suggest that the P.24 weighed around 2100-2200lb.
I did at one stage have a USAAF report on the P.24, which evidently didn't like some of the features of the engine - like the cranks not having counterweights.
One Fairey engine fan has suggested that the PV12 was a response to the P12. Not sure that it was, but the P.12 was earlier, and its power suggests it was a competitor to the Kestrel. Weight wise it looks lighter than the Merlin, but the early Merlins were similar before they had to be strengthened.
The Peregrine, a development of the Kestrel, weighed much the same as the P.12 and demonstrated more power potential (885hp vs 720hp).
Having just read your thread, it has just occurred to me that you and shortround6 might be right.
That would be an interesting read. Regarding the Fairey fan's claim, unless he's able to produce concrete evidence, I would be tempted to believe Mr Lumsden's account, as this book is quite a hefty tome. Lumsden trawled through the archives to produce the info contained within.
Here's a bit more from the book:
"If there was any confusion (conceivably intentional on the part of the company) about the V-12 engine, this was nothing by comparison with that which surrounded the second and radically new type of Fairey Prince; the 'double engine'. Pursuing the Prince theme has been an intriguing exercise. Grham Forsyth [Chief engine designer for Fairey] had very ingenious ideas about a double engine in the shape of a vertical 'H'. His idea was that each vertically-opposed half should operate quite independently, each driving a separate unit of a pair of co-axial counter rotatingand constant speed feathering propellers, with independent reduction gears on a commom crank case. For long economic overseas patrols, this is an interesting solution, offering twin twin-engine reliability from a 'single-engine' installation without inconvenient assymetric characteristics.The Royal Navy was known to be interested and Fairey himself was well known in the Admiralty. The idea of an H shaped engine was of course not new at the time. Frank Halford's air cooled 16-cylinder Napier Rapier and 24-cylinder Dagger, both of which had twin crankshafts geared together were in RAF use and widely advertised.
Complete official company records have been hard to discover but thanks to the researches and personal recollections of Sir Peter Masefield (a redoubtable historian, who, in his early years worked at Fairey's 'Great West Aerodrome' headquarters at Hayes}, some most revealing facts have emerged. Indeed, he himself made a number of flights in a Fairey Battle test bed, behind a 24 cylinder Fairey P-24 Double Prince.
Almost at the end of frustrating searches into these little known engines, an unpublished series of engine data sheets, dated 5 March 1941 from Sir Roy Fedden's Bristol archives came to light and included some unexpected information on the Fairey engines. As with so many long lost sources of information, total reliance on its accuracy at first seemed unwise, although the source of it was as impeccable as it could be. And then, at the very last minute, some long lost details of the Fairey P-24 Monarch were, thankfully made available to the author.
The unique new layout, in accordance with the novel ideas of Graham Forsyth, was intended to appear in two versions with 16 and 24 cylinders and used the same bore and stroke as the earlier Prince. In the Fairey system, the H-16 was to be a 16 cylinder engine, retaining the name 'Prince'. However, the name 'Monarch' was adopted for the 24 cylinder H-shaped P-24 engine in the first drawing, dated 29 August 1932.
Exactly what was the eventual outcome of the proposed 16-cylinder engine was still unclear at the time of writing, but happily, an engine called a Fairey Prince is carefully preserved at the FAA Museum at Yeovilton. The engine was originally rescued from a scrap yard in Kingston-upon-Thames after WW2. This unique engine is believed to be a P-24 Monarch. All the surviving Fairey drawings and data, signed out and authorised by A.G. Forsyth call it so. It is a vertical, H-shaped engine with side mounted superchargers. Therefore it is a rare, if not the uniquely surviving Fairey four speed, two stage engine. The photograph of a Prince engined Battle, having one engine run up also show four exhaust stubs top and bottom, suggesting H-16. The drawings show, however that the six exhausts in each bank were combined in four outlets, an arrangement also adopted by RR in certain instances.
The first Monarch to be built was installed in Fairey Battle K9370 in October 1938 and had a civil type test in May and June 1939. It achieved 50 hours without incident with fixed pitch contra-rotating propellers, being first flown by Chris Staniland in June. Tests went so well that it was cleared for flight trials of 120 hours and it was delivered to RAE Farnborough on 12 July 1941, having completed a 50-hour bench test and 87-hours flying in the Battle. While there it was installed in the large wind-tunnel for the study of contra-rotating propeller effects, together with thrust and propeller blade strain gauge tests. It was submitted to 15 hours testing at take-off power without trouble."
More soon
fastmongrel
1st Sergeant
Keep it coming nuuumannn facinating stuff. I love all the might have been and never were engines.
WJPearce
Airman 1st Class
Hello all,
As far as the 4-speed, 2-stage supercharger is concerned, I agree with Shortround. Each "half" of the engine had one 2-speed, 1-stage supercharger. So there were two superchargers on the engine, but each one only fed half the engine.
In a 1941 report from Wright Field (linked at bottom), it was stated the most interesting feature of the engine that deserved further study was the counter-rotating prop set-up. I feel that if the supercharger were indeed a 4-speed, 2-stage unit, it would have been very worthy of further study, especially in 1941. The document also gives a "Low Ratio" and a "High Ratio" power ratings for the engine. Again, makes me think "2-speed."
I love Lumsden's book but I do not agree with it regarding the 4-speed, 2-stage supercharger. Of course, he wrote the book and did the research, so take this post for what it is worth. Read the docs below and post what you think. I am eager for more information on these engines.
Docs (hard to read):
http://www.enginehistory.org/Misc/P150137.pdf
http://www.enginehistory.org/Misc/P152543.pdf
http://www.enginehistory.org/Misc/P161688.pdf
WJP
As far as the 4-speed, 2-stage supercharger is concerned, I agree with Shortround. Each "half" of the engine had one 2-speed, 1-stage supercharger. So there were two superchargers on the engine, but each one only fed half the engine.
In a 1941 report from Wright Field (linked at bottom), it was stated the most interesting feature of the engine that deserved further study was the counter-rotating prop set-up. I feel that if the supercharger were indeed a 4-speed, 2-stage unit, it would have been very worthy of further study, especially in 1941. The document also gives a "Low Ratio" and a "High Ratio" power ratings for the engine. Again, makes me think "2-speed."
I love Lumsden's book but I do not agree with it regarding the 4-speed, 2-stage supercharger. Of course, he wrote the book and did the research, so take this post for what it is worth. Read the docs below and post what you think. I am eager for more information on these engines.
Docs (hard to read):
http://www.enginehistory.org/Misc/P150137.pdf
http://www.enginehistory.org/Misc/P152543.pdf
http://www.enginehistory.org/Misc/P161688.pdf
WJP
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johnbr
2nd Lieutenant
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wuzak
Captain
Thanks for those WJP. I lost those when my last computer blew up.
Also thanks John, the image of the P-24 clarifies a few things in my mind from the reports.
From the second report (P152543) we know the following things:
Bore: 5.25in (133.35mm)
Stroke: 6in (152.4mm)
Capacity: 3117cu.in (51.08l)
Rated Power:
Takeoff: 2100/2140hp @ 3000rpm
Normal Power:
Low Ratio: 2030hp @ 2600rpm @ 5,000ft
High Ratio: 1780hp @ 2600rpm @ 12,000ft
Military Power:
Low Ratio: 2100hp @ 3000rpm @ 6,000ft
High Ratio: 1850hp @ 3000rpm @ 13,000ft
Dry Weight: 2180lb (also noted as 2250lb)
The report states that the hours run at power levels over 2000hp do not support the ratings (the ratings were supplied to the USAAF by Fairey).
At 30,000ft the Merlin 60-series produced 160hp more than the P-24.
The engine used 3 valves per cylinder, with two inlet valves and a single exhaust. The inlet valves were mounted in a line transverse to the crankshaft axis.
4 inlet ports are fed by each of the inlet manifolds. The inlet manifolds are integral with the barrels (see picture), the air path requiring many tight turns. It was also considered that this would be difficult to change/develop.
The inlet valves did not have sodium cooling. The exhaust valves may have, but the valve actuation design precluded the use of fully cooled stems.
The camshafts were supported by 4 bearings only. These were two at each end and two in the centre, leaving long spans between support bearings.
The crankshafts had no counterweights.
The engine had no provision for dealing with crankshaft torsional vibration. (RR engines didn't have TV dampers, but did use torsionally flexible shafts to transmit power to accesories.)
The reduction gear pinions were directly mounted on the ends of the crankshafts (not normal practice).
The supercharger drive gears were though to need considerable development.
The heads were connected to the barrels by studs fitted to the barrels. Normal practice was to use studs fitted to the crankcase.
Ron Hazen, of Allison, is quited in the report as saying "Mr. Devereux expressed himself as believing the design was considerably cleaner than the Sabre and a much better production job although he thought that two or three years development remained before it would be ready for production. I gathered that it was in its present stage a fairly good engine at 1500 horsepower and 2250 pounds."
Personally I can't see how the P-24 was a "cleaner" design than the Sabre being wider and taller than the Sabre, slightly lighter and about the same length. Production wise the conventional poppet valves would have made life easier, but other features of the P-24 may have neagted that. I'd also suggest that the Vulture would have provided the same power as the P-24 in a more compact package, at about the same weight (if/when they changed the reduction gear system).
Also thanks John, the image of the P-24 clarifies a few things in my mind from the reports.
From the second report (P152543) we know the following things:
Bore: 5.25in (133.35mm)
Stroke: 6in (152.4mm)
Capacity: 3117cu.in (51.08l)
Rated Power:
Takeoff: 2100/2140hp @ 3000rpm
Normal Power:
Low Ratio: 2030hp @ 2600rpm @ 5,000ft
High Ratio: 1780hp @ 2600rpm @ 12,000ft
Military Power:
Low Ratio: 2100hp @ 3000rpm @ 6,000ft
High Ratio: 1850hp @ 3000rpm @ 13,000ft
Dry Weight: 2180lb (also noted as 2250lb)
The report states that the hours run at power levels over 2000hp do not support the ratings (the ratings were supplied to the USAAF by Fairey).
At 30,000ft the Merlin 60-series produced 160hp more than the P-24.
The engine used 3 valves per cylinder, with two inlet valves and a single exhaust. The inlet valves were mounted in a line transverse to the crankshaft axis.
4 inlet ports are fed by each of the inlet manifolds. The inlet manifolds are integral with the barrels (see picture), the air path requiring many tight turns. It was also considered that this would be difficult to change/develop.
The inlet valves did not have sodium cooling. The exhaust valves may have, but the valve actuation design precluded the use of fully cooled stems.
The camshafts were supported by 4 bearings only. These were two at each end and two in the centre, leaving long spans between support bearings.
The crankshafts had no counterweights.
The engine had no provision for dealing with crankshaft torsional vibration. (RR engines didn't have TV dampers, but did use torsionally flexible shafts to transmit power to accesories.)
The reduction gear pinions were directly mounted on the ends of the crankshafts (not normal practice).
The supercharger drive gears were though to need considerable development.
The heads were connected to the barrels by studs fitted to the barrels. Normal practice was to use studs fitted to the crankcase.
Ron Hazen, of Allison, is quited in the report as saying "Mr. Devereux expressed himself as believing the design was considerably cleaner than the Sabre and a much better production job although he thought that two or three years development remained before it would be ready for production. I gathered that it was in its present stage a fairly good engine at 1500 horsepower and 2250 pounds."
Personally I can't see how the P-24 was a "cleaner" design than the Sabre being wider and taller than the Sabre, slightly lighter and about the same length. Production wise the conventional poppet valves would have made life easier, but other features of the P-24 may have neagted that. I'd also suggest that the Vulture would have provided the same power as the P-24 in a more compact package, at about the same weight (if/when they changed the reduction gear system).
This is great info wuzak and WJPearce. I agree about the superchargers that Lumsden mentions, but I suspect he doesn't mistake their output each, since he mentions in one paragraph "It is a vertical, H-shaped engine with side mounted superchargers" which might confirm that the proposition of "four-speed two-stage" that he offers is his description, not necessarily how the supercharger is actually arranged.
Examining Rob Leigh's photo of the engine at Yeovilton closely seems to confirm Lumsden's conclusion that the FAA Museum's engine is the P-24; look at the raised horizontal castings going from the centre to the exhaust ports; these look like they could contain the rocker push rods. The Whirlwind helicopter in the background is HAS.7 XG594; When I was younger and living in the UK I used to clamber all over this aircraft; I know it well!
More from Lumsden as promised:
"The H-24 engine of 51.078 litres was intended initially to develop 2,000 hp and eventually to achieve 3,200 hp. Early in WW2, in discussions at the Ministry of Aircraft Production under Lord Beverbrook, a proposal was made that the H-24 should be built by Ford in the USA, to power the Republic P-47 Thunderbolt. [I did not know that!] As a preliminary while development work was done on the H-24, the Battle test bed was sent with a spare engine by sea to the USA on 15 January 1942 and while at Wright Field, it flew 250 hours in 18 months, after which it was returned to britain and is now probably the sole survivor. A second P-24 was installed in a Battle at the RAE; this time equipped with fully feathering propellers.
Further development of the Prince was abandoned in 1943 while Sir Richard Fairey was in the USA. The P-24, had it been adopted as Fairey originally intended, would have given the Battle twice the power and a rather more adequate performance. What eventually happened to the H-24 is, as Sir Peter Masefield has recorded is, unfortunately 'still lost in the mists of wartime affairs'. It is a sad reflection on wartime finances and politics that, with a limited amount of money to go round and the existence of a number of established aero-engine manufacturers, a very senior government official was heard to express the view that 'Fairey would have to go it alone, or fold up'. This was a pity because with real support, Fairey and Forsyth might well have achieved useful results. By that time, Fairey is said to have expended the enormous sum of over 1000,000 Pounds Sterling of his own money on the development of the Prince engines; in 1992 terms amounting to a figure nearer to a million."
That's it from me, folks.
Examining Rob Leigh's photo of the engine at Yeovilton closely seems to confirm Lumsden's conclusion that the FAA Museum's engine is the P-24; look at the raised horizontal castings going from the centre to the exhaust ports; these look like they could contain the rocker push rods. The Whirlwind helicopter in the background is HAS.7 XG594; When I was younger and living in the UK I used to clamber all over this aircraft; I know it well!
More from Lumsden as promised:
"The H-24 engine of 51.078 litres was intended initially to develop 2,000 hp and eventually to achieve 3,200 hp. Early in WW2, in discussions at the Ministry of Aircraft Production under Lord Beverbrook, a proposal was made that the H-24 should be built by Ford in the USA, to power the Republic P-47 Thunderbolt. [I did not know that!] As a preliminary while development work was done on the H-24, the Battle test bed was sent with a spare engine by sea to the USA on 15 January 1942 and while at Wright Field, it flew 250 hours in 18 months, after which it was returned to britain and is now probably the sole survivor. A second P-24 was installed in a Battle at the RAE; this time equipped with fully feathering propellers.
Further development of the Prince was abandoned in 1943 while Sir Richard Fairey was in the USA. The P-24, had it been adopted as Fairey originally intended, would have given the Battle twice the power and a rather more adequate performance. What eventually happened to the H-24 is, as Sir Peter Masefield has recorded is, unfortunately 'still lost in the mists of wartime affairs'. It is a sad reflection on wartime finances and politics that, with a limited amount of money to go round and the existence of a number of established aero-engine manufacturers, a very senior government official was heard to express the view that 'Fairey would have to go it alone, or fold up'. This was a pity because with real support, Fairey and Forsyth might well have achieved useful results. By that time, Fairey is said to have expended the enormous sum of over 1000,000 Pounds Sterling of his own money on the development of the Prince engines; in 1992 terms amounting to a figure nearer to a million."
That's it from me, folks.
wuzak
Captain
I'm not sure what you are referring to precisely, but I believe what you are talking about are the inlet manifolds. As these are integrally cast with the barrels and cooling jackets it is likely that the inlet air would be heated on its way to the cylinder.
wuzak
Captain
Just to clarify what I mean, I believe that the P-24 had an overhead camshaft, and not pushrods.
I have indicated on the picture the intake airflow path
Not the best ever intake design....
I have indicated on the picture the intake airflow path
Not the best ever intake design....
wuzak
Captain
This is how I interpret the valve and manifold layout of the Fairey P-24:
Blue is intake air, red is exhaust. Looking at the top pair of cylinder banks.
Blue is intake air, red is exhaust. Looking at the top pair of cylinder banks.
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fastmongrel
1st Sergeant
Nice work wuzak. Definitely looks like an external inlet manifold would have had better breathing, 90 degree bends arent good for airflow.
wuzak
Captain
A couple of alternatives that they may have considered.
One would be to feed the inlets in the normal manner. This would mean two inlet ducts for each half of the engine, but the exhaust would be simpler and probably provide more exhaust thrust. This would be more complicated for the distribution from the superchargers. This is the system the H-Merlin would have used, as the blocks and heads for that were standard 60-series.
If they geared the two halves together, ala Dagger, Rapier and Sabre, they could simplify the supercharger, needing only the two outlets to provide air for the engine. It would also have meant less controls required, but the loss of the ability to control each half independently.
One would be to feed the inlets in the normal manner. This would mean two inlet ducts for each half of the engine, but the exhaust would be simpler and probably provide more exhaust thrust. This would be more complicated for the distribution from the superchargers. This is the system the H-Merlin would have used, as the blocks and heads for that were standard 60-series.
If they geared the two halves together, ala Dagger, Rapier and Sabre, they could simplify the supercharger, needing only the two outlets to provide air for the engine. It would also have meant less controls required, but the loss of the ability to control each half independently.
wuzak
Captain
If they chose to have the cylinders horizontally, they could have had the exhausts exit between the banking, like for the Sabre.
Then they could have the inlets top and bottom in a similar fashion to the Sabre.
Then they could have the inlets top and bottom in a similar fashion to the Sabre.
- Thread starter
- #18
wuzak
Captain
The Fairey P.24 Civil Type Test was undertaken between 13 May 1939 and 14 June 1939.
The rated output was 1205hp @ 10,500ft at 2400rpm.
The maximum output was 1450hp @ 10,500ft, maximum speed 2750rpm.
Bore: 5.254" (133.5mm)
Stroke: 6.00" (152.3mm) [from the report, should be 152.4mm if it is 6"]
Capacity 3124.3ci (51.2l)
BMEP at rated hp at "International RPM" was 127psi.
The carburetors were fitted with automatic boost controls.
Nett dry weight was 2202lb, gross dry weight (not including propeller hubs or engine mounting) was 2329lbs.
The rated output was 1205hp @ 10,500ft at 2400rpm.
The maximum output was 1450hp @ 10,500ft, maximum speed 2750rpm.
Bore: 5.254" (133.5mm)
Stroke: 6.00" (152.3mm) [from the report, should be 152.4mm if it is 6"]
Capacity 3124.3ci (51.2l)
BMEP at rated hp at "International RPM" was 127psi.
The carburetors were fitted with automatic boost controls.
Nett dry weight was 2202lb, gross dry weight (not including propeller hubs or engine mounting) was 2329lbs.
