Fulmar in 1941/42/43: feasible and/or plausible upgrades?

[tomo pauk]

Sometimes a much derided 'soldier', Fairey Fulmar was there when needed, providing a good important service in the rough days of early ww2. It's good qualities (great combat range, useful punch ammo count, 2 pairs of eyes, good ditching qualities) were many times too much a burden for it's engine, trying to squeeze performance out of the sizable airframe.
So what kind of upgrades would made the Fulmar to hold the line even better until the replacement is around ( historically, some time late 1943/early 1944)? Upgrades should be non-earth-shaking, simple if you want, plausible feasible, so we could get the improved planes quick on the decks.

 

[Shortround6]

Uh, Tomo,

"The Firefly was designed by H.E. Chaplin at Fairey Aviation; in June 1940, the Admiralty ordered 200 aircraft "off the drawing board" with the first three to be the prototypes. The prototype of the Firefly flew on 22 December 1941.[3] Although it was 4,000 lb (1,810 kg) heavier than the Fulmar (largely due to its armament of two 20 mm Hispano cannon in each wing), the Firefly was 40 mph (60 km/h) faster due to improved aerodynamics and a more powerful engine, the 1,735 hp (1,294 kW) Rolls-Royce Griffon IIB."

Futzing about with "improved" Fulmars is not likely to help the Firefly situation. Why it took so long for the Firefly to go into operation I have no idea.

First Merlin production Merlin 32 ( 1,645 hp (1,230 kW) at 3,000 rpm at 2,500 ft (762 m)), doesn't show up until 17 June 1942. It may be the first of the low altitude cropped impeller engines?

 

[tomo pauk]

Well, I'm trying to avoid 'eating into' Firefly allocated assets as much as possible. The 1st flight was made during late 1941 - meaning Fulmar will soldier on for at least 1 year and half, even if the Fairey's engineers are the best on the planet.
About the engine situation - Fulmar never flew with 2-speed engine aboard. Even the Merlin 30 was not able to be pushed beyond +12 psi, compared with it's 2-speed cousins (+14 psi in low gear, +16 in high gear, on 100/130 fuel). So maybe going with Merlin 20 series? Clip the wings a little bit, too?

I'm at loss why would even 10% of the improved speed of the Firefly should be credited to better aerodynamics (per quoted text) - the single stage Griffon at ~ 20000 ft was providing maybe 50% as much power as Merlin 30?

 

[GregP]

Upgrade it to "retired" status.

 

[tomo pauk]

No that's a contribution

 

[RCAFson]

There an extensive analysis of Fulmar performance here:
http://www.ww2aircraft.net/forum/aviation/fulmar-ii-versus-f4f-4-under-10-000-ft-29212.html
including Fulmar and Firefly performance curves.

IMHO, adding either a Merlin XX or 45 would have given the Fulmar somewhat better maximum speeds and climb rates, especially when these engines were rated at 14 and 16lb boost, since the FTH would be improved in both cases while improved boost should give better performance than the Merlin 30 even at the 30's FTH.

 

[tomo pauk]

Merlin 30 was basically the Merlin 20 series with low supercharger gear only (contrary to the Merlin 45/50, basically the Merlin 20s with high supercharger gear only). Installing a 'normal' 2 speed Merlin 20 series should give the historical performance with low gear clutched in, and much better performance above 12-15000 ft, where the high gear is clutched in. The Merlin 45/50 should give similar performance, above 12-15000 ft, as Merlin 20s indeed.

 

[RCAFson]

Merlin 30 was basically the Merlin 20 series with low supercharger gear only (contrary to the Merlin 45/50, basically the Merlin 20s with high supercharger gear only). Installing a 'normal' 2 speed Merlin 20 series should give the historical performance with low gear clutched in, and much better performance above 12-15000 ft, where the high gear is clutched in. The Merlin 45/50 should give similar performance, above 12-15000 ft, as Merlin 20s indeed.

My speed guesstimate for a Fulmar with a Merlin 45 would be ~310 mph at ~12000ft with 16lb boost (1515hp at 3000rpm) while a Merlin XX should give ~280mph at ~7000ft (MS = 1485hp at 14lb boost @ 3000rpm)and ~312 mph at ~14000ft (FS = 1490hp at 16lb @ 3000rpm). Peak combat climb rates would be ~2100fps and ~5 mins to 10,000ft and ~10 mins to 20,000ft. The Fulmar would substantially outperform the F4F-4 and Martlet II/IV.

 

[wuzak]

But not the Seafire, which is what Fairey should probably have been building/developing!

 

[RCAFson]

But not the Seafire, which is what Fairey should probably have been building/developing!

The Fulmar had far more range and endurance than a Seafire and a lot more firepower (750rpg or 38secs or 1000 rpg or 50sec firing time) than a Seafire, especially a hypothetical Mk1 with 8 x .303 with 330rpg. Overall a Fulmar would probably score more kills per sortie than a Seafire I, given the typical opposition, especially with an upgraded engine plus the Fulmar would have a much lower operational loss rate per sortie. The Seafire could better handle enemy SE fighters but that wasn't really a major problem for the FAA anyways.

 

[nuuumannn]

One of the major issues with the FAA is that they never really seemed to have enough aircraft in theatre initially, particularly in the Mediterranean. Granted, they were limited by the number of aircraft that could be carried aboard their carriers, but I would have thought that more Fulmars, rather than any modifications to the basic design, which would have delayed aircraft getting to the front line, would have been a better interim solution until a more effective aircraft came along.

 

[MacArther]

How about dropping the rear position crewmember and all the equipment associated with that area? Would the weight savings be worth it?

 

[fastmongrel]

One of the major issues with the FAA is that they never really seemed to have enough aircraft in theatre initially, particularly in the Mediterranean. Granted, they were limited by the number of aircraft that could be carried aboard their carriers, but I would have thought that more Fulmars, rather than any modifications to the basic design, which would have delayed aircraft getting to the front line, would have been a better interim solution until a more effective aircraft came along.

There were times when there werent enough Fulmars to fill the hanger of even one Fleet Carrier in the Med. I believe they were down to 30 or so Fulmars at one point and that was everything even the ones in repair shops.

 

[Shortround6]

How about dropping the rear position crewmember and all the equipment associated with that area? Would the weight savings be worth it?

It would improve the climb some but the change in speed would probably be under 5mph. That is assuming there is no center of gravity shift that would require ballast.

 

[Kryten]

Fleet Air Arm requirements were not just for a fighter role however, the second seat was invaluable on Recce and anti submarine operations, multi purpose was the name of the game with the handicaps that entailed!

 

[nuuumannn]

It would improve the climb some but the change in speed would probably be under 5mph. That is assuming there is no center of gravity shift that would require ballast.

I think improving the Fulmar is a bit of a lost cause; it was too slow, slow in the climb and slow in level speed. What the FAA really needed was a good single-seat fighter, they just didn't realise it when the Fulmar was conceived (hindsight is wonderful). Also, the FAA's insistence on catering too much to the needs of the navigator/observer in its aeroplanes proved to be a ball and chain. The Barracuda was another airframe whose concentration on the observer spoiled it; The nav had a big space below the wing with clear windows for good visibility; this meant the aircraft had to be a high/shoulder wing design. Placing the wing at shoulder level meant that when the Youngman flaps were used as dive brakes they blanketed the elevators, which were eventually moved to near the tip of the fin, although stability was always an issue even after this had been done. If you want a maritime patrol platform, don't use a dive bomber or a single-engine fighter.

If you are going to do something with the Fulmar, either take your chances with interim solutions like the Seafire and Sea Hurri (as well as a handful of Martletts) whilst waiting for Lend Lease to kick in and supply excellent purpose built naval fighters, or start afresh with a purpose designed single-seat carrier based fighter that didn't use a land based single engined day bomber as its basis.

 

[RCAFson]

The Fulmar had a lot of capabilities, such as a good dive bombing capability and good range with the 60 gal DT, that were never fully exploited, probably because of the small production numbers. Boosting the production rate of the Fulmar and it's performance with a more powerful engine would have been very worthwhile, IMHO. The long range/long endurance scout/patrol fighter concept was a good one, IMHO and the Fulmar has the kill stats to back it up.

 

[tomo pauk]

Now that we talk about bombed-up Fulmar - maybe the Zero/Oscar would be hard pressed to thwart a bombing run made by Fulmars?

The long range fighter that still can make 310 mph might give the defender better chances for multiple interceptions, rather than a short range interceptor that can do 330-350 mph?

 

[fastmongrel]

The long range fighter that still can make 310 mph might give the defender better chances for multiple interceptions, rather than a short range interceptor that can do 330-350 mph?

True but how many Wildcat/Martlets or Sea Hurricanes are doing 330 let alone 350mph.

I love how the Fulmar annoys so many people

 

[Shortround6]

I see the S.P.O.O.S.E.S.* is back in full session.

Please note that what ever boost level you can get out of a Merlin 45 or XX series engine is for about 5 minutes only. The 30 minute climb ratings and the max cruise ratings didn't change.

Merlin 30 was good for 1260hp at 8750ft. the only way you are going to get a Fulmar to 310mph at 10,000ft is with a large rocket strapped to it.

* Silk Purse Out Of Sow's Ear Society.