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The V-1710's air intake was above the nose as it had a downdraft carburettor.
The Merlin versions needed an intake below the nose because the Merlin had an updraft carburettor.
Doesn't sound like "the designers thought right from day one of the Merlin conversion".
And if Rolls-Royce hadn't come up with the 2 stage engine, the P-51 may never have been converted.
They are permanently mixed up, Griffon and Griffin as well as Gryphon are all names for the same mythical beast with the legs body and tail of a lion and the wings and head of an eagle.Because the 37 litre V12 engine which actually flew in WW2 was derived from a much earlier design of the same bore and stroke which lay dormant at RR dating from just after the Schneider Trophy days, which WAS called "Griffin"
The two names were often mixed up ever-after.
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Hi,Though there were also a series of RR piston engines named after rivers like the Exe and Pennine?. I do not think any of those actually went into production and I think all were best forgotten.
Yes, but the Griffon name here was the particular Bird of Prey, Griffon-a type of Vulture.They are permanently mixed up, Griffon and Griffin as well as Gryphon are all names for the same mythical beast with the legs body and tail of a lion and the wings and head of an eagle.
Allison was a sister company owned by General Motors. NAA was thinking Allison even before the V-1710 was ever flight tested - all the way back to XC-602 RFP for two seat Pursuit in 1935. Lee Atwood designed the P-198 in anticipation of competeing but the RFP was pulled by Materiel Division.When we designed the mustang was there a better choice than a V-1710 ? I'm talking P-51A and A-36 time period what were the options was Naiper still making their 24 cylinder H-patteren engine ? I'm not an allison guy so thats why im asking did we have better options ?
To the questions regarding 'chin' vs 'other' carb intake design.
There was another variation on location and configuration explored for better aerdynamics on the XP-51B. Visualize the lower cowl line of the XP-51J
The carb updraft inlet was located beneath the carb inlet of the engine, oval in shape and flush with the lines of the cowl. I don't have the documents discussing the design but it seems obvious that whatever slight improvement of parasite drag (form) of CDp=0.0004 (comparable to gun ports on P-51D) that the obvious 'potential FOD vacuum cleaner effect' of that location was not a better idea.
I did not discuss the Allison versions as my post was only in relation to the Merlin variants.
Though there were also a series of RR piston engines named after rivers like the Exe and Pennine?. I do not think any of those actually went into production and I think all were best forgotten.
The Exe was named for a river, while the Pennine was named for a mountain range.
A development of the Pennine was to be called the Snowdon.
So maybe air-cooled military engines were to be named for rivers, air-cooled engines for civilian use for British mountains?
The Crecy, a 2-stroke, was named after an historic battle.
Liquid-cooled 4-strokes were named after birds of prey.
The Exe began as the "Boreas" after the Greek God of the cold north wind, storms and winter. According to Lumsden "British Piston Aero-Engines and their Aircraft" the name was changed "because it infringed Bristol's Greek mythology names".The Exe was named for a river, while the Pennine was named for a mountain range.
A development of the Pennine was to be called the Snowdon.
So maybe air-cooled military engines were to be named for rivers, air-cooled engines for civilian use for British mountains?
The Crecy, a 2-stroke, was named after an historic battle.
Liquid-cooled 4-strokes were named after birds of prey.
I believe those are the gear wells with inboard gear doors in the up position (versus the droop).What are the underwing intakes shown in that picture?
To the questions regarding 'chin' vs 'other' carb intake design.
There was another variation on location and configuration explored for better aerodynamics on the XP-51B. Visualize the lower cowl line of the XP-51J
The carb updraft inlet was located beneath the carb inlet of the engine, oval in shape and flush with the lines of the cowl. I don't have the documents discussing the design but it seems obvious that whatever slight improvement of parasite drag (form) of CDp=0.0004 (comparable to gun ports on P-51D) that the obvious 'potential FOD vacuum cleaner effect' of that location was not a better idea.
It wasn't a variant per se. A short lived modification that was restored to 'original' before turing over to Wright Field in May 1943. I don't know whether it was 352 or 421, but suspect 352 (#1 XP-51B) while #2 at Ames solving the Rumble issue. As I think I said, I don't have drawings or correspondence on this one.Most interesting. Given that NAA were heavily into keeping FOD out of the engine and had filters etc in all the other variants (and designs) I would expect this variant to also have them but I cannot envisage where they would have located them.
Is there any other information publicly available on this variant?
It was far more reliable than the Merlin at all stages of the war,
Do you have any evidence to support that.It was far more reliable than the Merlin at all stages of the war,