1 engine vs 2 engine fighters

[SPYINTHESKY]

Not really. The ORBs of both squadrons are available and show that there were not many weeks when they could field a double figure number of serviceable aircraft between them.

For example, you often see accounts of Whirlwinds flying 'Rhubarbs' to aerodromes in France, but they often fail to mention that the number of Whirlwinds involved was sometimes only two!

Cheers

Steve

Whirlwinds were held back from the BOB which also precludes any real assessment of their capabilities in the role that they were designed for i.e. killing bombers. As the only cannon armed fighter available at the time it seems from available evidence they were being prepared for the role of ground attack against tanks and soft vehicles should the invasion come, preservation was the priority, as their numbers were finite with numbers long set by that time, so air combat losses were just not acceptable.

Thereafter, especially as there was going to be no effort to improve their high level performance (which progressively became more important in air combat), or indeed any aspect of the aircraft sadly, their ground attack (or shipping) role was set in stone. As it turned out they were exceptional in that role and ended up as the longest serving single Mk British fighting aircraft of the war. When the pilots were finally re equipped with Hurricanes in this role they were not at all impressed, but as you say numbers even in the early days were always slow to arrive (even after development delays) because Westland were forced to give priority to other aircraft, not to mention the overall lack of faith in them as a producer at the time, they not being one of the MOD established 'favourites'.

Perhaps its greatest contribution as a fighter was in being used by the Americans to perfect the P38 Cannon installation.

 

[Airframes]

Not really 'held back' from the BoB. There were only five in service with 263 Sqn in Scotland by mid August, and none of these were serviceable. By the time deliveries, and serviceability, had caught up, and the Sqn had 'worked up' on the type, the BoB was over.
They did not become properly operational until December 1940, when the Squadron moved to Exter.

 

[tomo pauk]

...
Had the WW been developed or [the Whirlwind was] equipped with Merlins as originally planned it would have been a true test between twins and singles of the time but sadly it never happened for reasons other than its innate qualities.

...
Perhaps its [Whirlwind's] greatest contribution as a fighter was in being used by the Americans to perfect the P38 Cannon installation.

(my comment in brackets, my bold)
As a person that rates the Whirly high, I'll politely ask for surces for the quoted claims.

 

[Shortround6]

By the end of the war there were only few lightweight dogfighters left in production anywhere but Russia and Japan.
A late model Spitfire going about 9000lbs clean gross.

The big singles that showed up at the end of war were pushing the envelope pretty well as it was. That is with drop tanks they had about all the range that could be reasonably used given pilot fatigue on long missions , they could do over 450 mph and they could carry four 20mm cannon (P-47N had eight . 50s) and had fair amount of ammo.

With so few from each country and with different start dates and development times it gets a bit tough to draw conclusions as to what was state of the art at any given time but the big singles had engines of 2000hp and up (some over 2500hp) and any twin was going to need something over 3000 hp to match them.

A single dogfight doesn't prove much as it only tests two pilots under one set of conditions.

Try pitting an F4U-5 against an F7F-4 but do it at 30,000ft.

 

[stona]

Whirlwinds were held back from the BOB which also precludes any real assessment of their capabilities in the role that they were designed for i.e. killing bombers. As the only cannon armed fighter available at the time it seems from available evidence they were being prepared for the role of ground attack against tanks and soft vehicles should the invasion come, preservation was the priority, as their numbers were finite with numbers long set by that time, so air combat losses were just not acceptable.

The Whirlwind was not held back from the Battle of Britain. No. 262 Squadron didn't receive its first Whirlwind (P6966) until 10th July 1940. The intention was to form one Flight (C ) to develop the aircraft for squadron use. At the end of July the squadron had just two Whirlwinds. In early August C Flight was disbanded, such were the teething problems. Dowding did plan to use them as tankbusters should an invasion be attempted, but there were never more than a handful available. What they might have achieved we will never know.

The reason they were never considered for operational use in 11 Group during the battle of Britain, even if a couple of Flights could have been made available in the late stages of the Battle was simple. Most combat was taking place at altitudes above or close to the Whirlwind's service ceiling. They couldn't be used as bomber killers, they could barely reach the bombers. In fact they were never available or operational for any role during the BoB.

On 4th November, after 'Sealion' was had been 'postponed', the 263 Squadron ORB notes:

"Of fifteen aircraft built, the squadron had eight, but four were grounded with engine problems and two were unserviceable, leaving two for training."

In the end Sholto-Douglas had enough. He wrote to Westlands.

"It is now five months since 263 Squadron re-formed, allegedly on Whirlwinds. I am taking its Hurricanes away and making it operational on Whirlwinds at RAF Exeter. It is up to you to make the squadron's initial strength up to sixteen at once."

The Squadrons reaction was rather different, the ORB noting.

"It was with great regret that leave was taken of the Hurricanes."

So, finally, twenty six months after the maiden flight and five months since first delivery the Whirlwind was declared operational. It was too late for the BoB, it was December 1940.

Cheers

Steve

 

[GregP]

The F7F won't need to be at 30,000 feet. It is a fleet defense fighter, not an escort fighter.

Try it at S.L. to 15,000 feet, which is where anything trying to attack a Naval task force will have to be to do any damage.

 

[Shortround6]

Hmmmm, you want to explain that to the USN in late 40s. Around 500 F4U-5 built and I would guess that most of them were classified as fleet defense fighters, at least the ones equipped with radar. Granted it turned out that no enemy or potential enemy came up with plane that operated at the altitudes the F4U-5 could operate at.

However the point was that there weren't that many of these late war/post war piston engine fighters and trying to draw any conclusion about general trends from a single rather impromptu match-up really isn't going to tell us much.

DH Hornet used two stage engines while the Sea Fury used a single stage engine with an FTL in high gear of 16,500ft.

The match up I suggested flips things, The F4U-7 having the most sophisticated two stage mechanical supercharger ever built in large numbers. It would give 1800hp at 30,000ft, no RAM for Military power.
The late model F7Fs got the same engines as the F8F-2 Bearcat a single stage supercharger with variable speed drive. 1700hp at 16,000ft Military power no RAM.

You want the F4U-5 to come down to the F7Fs best altitude where it would be lugging around 350lbs of excess supercharger plus inter-coolers and duct work.

I was pointing out that different match-ups could have different results than the original and we need to be careful about the conditions before declaring either the single engine or the twin "best" in any circumstances.

You want interesting?? how about the Hornet vs the F4U-5 and the Sea Fury vs the F7F?

 

[gumbyk]

Lets not forget at least one other inherent advantage to twin engine fighters, survivability when having lost one engine. Probably enough to get home or a controlled landing, but not enough to continue to fight. But with a single if it takes a hit and dies you are pretty well out of options.

I think this is over-estimated. As others have said, single-engine performance may not get you home. If it does, you're a sitting duck for any young fighter pilot trying for his first kill.
Couple that with twice the chance of getting hit in the engine, and getting hit in an engine during a turn, reduced roll rate, and I don't think that (generally) they provided all that they promised.

 

[GregP]

I don't WANT it Shortround, but the F7F was not designed nor used as a high-altitude fighter. The Corsair was never a high-altitude fighter, either, in US service. After WWII, it was a stop-gap fighter until they figured out how to get jets with enough power to be attack planes. That didn't "take" all that well until the A-10. So, the Skyraider was REALLY useful in Korea and Viet Nam.

I believe a lot of the F7Fs were used as night pickets around carriers and carrier task groups after the war, and they never encountered a Japanese fighter during the war. Being a WWII forum, I am confining my comments to WWII situations.

 

[Shortround6]

What started us in this "tangent" was a post trying to compare a DH Hornet to a Sea Fury, neither of which were aircraft that "served" in WW II, even if development started during the war.
SO I guess, according to you, we can't talk about them either?

and since they didn't serve in WW II I guess the over 500 Corsairs built with this engine

don't count as "high altitude" and can't be talked about either. even though testing started in late November 1944 on the basic power section and the two stage engine started testing on March 10th 1945.

Over 1/2 of the F5U-5s were equipped with radar

BTW first flight of the Prototype F4U-5 may have been on 21 December 1945. Three F4U-4 airframes were used as prototypes.
In any case the requirement/desire of the navy to have such planes was certainly of WW II origin.

 

[GregP]

I like the F4U-5 myself because it had all-metal wings. To be sure, the F4U-5's could get to high altitude, but by the time they were flying, they were not going to be first-line high-altitude fighters (I'd take one versus a Grumman F9F, myself). They might well have been the best available at sea over the oceans right after WWII ended, but there was nobody to fight since the war was over. But they made for a formidable Navy higher-altitude capability when none was needed.

I wasn't thinking of post-war when I posted above since this is mainly a WWII forum.

When they DID fight, they were used for ground attack in Korea, not for high-altitude anything.

 

[swampyankee]

I think this is over-estimated. As others have said, single-engine performance may not get you home. If it does, you're a sitting duck for any young fighter pilot trying for his first kill.
Couple that with twice the chance of getting hit in the engine, and getting hit in an engine during a turn, reduced roll rate, and I don't think that (generally) they provided all that they promised.

Not just was, is. There have been several F-18 crashes where the remaining engine quickly failed; in at least one of these was when one engine fodded the other. In a different aviation realm, back when I worked in the helicopter industry, it was found that two (and possibly three) engine helicopters had more forced landings due to transmission failures than single engine helicopters had due to engine failure or transmission failure. In other words, a single engine helicopter was less likely to have a forced landing.

 

[Dawncaster]

Try pitting an F4U-5 against an F7F-4 but do it at 30,000ft

Try it at S.L. to 15,000 feet

So I tried it.

Maximum speed and rate of climb for altitudes for F4U-5 and F7Fs.

I could not find SAC or ACP for F7F-4.

So I used ACP of F7F-3 for F7F-4's 460 mph maximum speed. (both had same -34W engine)

This is just addition of the F4U-5's performance summary and flight test data on F7F-3 ACP with estimated F7F-4 curve.

 

[GregP]

I'd take the Tigercat over the ocean and for any carrier landing, the Corsair over land ... or in a one-on-one dogfight.

But, most squadrons didn't have the choice to make. They flew what was assigned. The Navy wanted the Tigercat for a reason and they STILL want twin engines today.

 

[BiffF15]

Greg,

The USN today fly's the T-6 Texan II and T-45, both of which are SE. The newest USN/USAF/USMC fighter is SE. I'm not exactly sure what you are driving at, but if a SE aircraft can accomplish the defined mission, it's going to be more "cost effective" than it's multi engined friend. Don't get me wrong, I prefer two over one, but it will eventually come down to cost and meeting mission requirements.

Cheers,
Biff

 

[Shortround6]

It might not have been possible to carry the radar and missile load of the F-14 and get the performance desired using a single engine at the time the F-14 was conceived/designed. Performance including range/endurance.

AS Biff says, the choice of one or two engines comes down to mission requirements many times.

 

[BiffF15]

SR6,
The Eagle fell into the same category of mission requirements driving the final configuration. Engine technology, missile technology, and advanced manufacturing techniques along with every present costs are driving us towards a SE centric fighters in my opine.
Cheers,
Biff

 

[Shortround6]

As you say, changing technology can change designs.
Engine in the F-35 weighs a few hundred pounds less than one of the original engines in the F-14 and yet offers about double the non-afterburner power. and 85% of the power or both TF-30s in after burner.
Fuel burn is probably better too

 

[GregP]

Hi Biff,

The T-6 and T-45 are trainers. I'm talking fighters. The F-4 was a twin, the F-14 was a twin, the F-18 is a twin. A lot of people got home on the second engine in combat. The a-4 was a long-serving holdover from the 1950's, but the A-6 was a twin, too. Anyone who doesn't think the A-7 was the direct stepchild of the 1950s F-8 hasn't seen them side-by-side. The Navy flies assets when it has them and they are in service, but they acquired twins for the important planes from the F-4 forward. Let's face the facts here. The Navy is acquiring the F-35 because they were directed to, not because the Navy wanted it, though the Marines DID want a replacement for the AV-8Bs they lost. I just haven't spoken with anyone in the Marines who wanted the F-35 specifically. Today, you speak the party line or you get fired, and they're getting in line and talking it up, as expected. There are a lot of active-duty people who think the F-35 is a mistake, in every service that will fly or flies them.

But we are getting them, so the task is to learn to employ them correctly and they are in the process of that now. It seems to be doing well, at least in the press. I'm not anxious for combat just to prove it good or bad, and will gladly wait until it is actually needed to find out. Meanwhile, it seems to be maturing, though that hasn't helped the amount of weapons it can carry and stay stealthy.

I'll get back to WWII ... or shortly post-war. I'd still like to see a turboprop Skyraider Attack plane with modern avionics. We have the technology now, and would not use that unreliable, geared transmission that the Skyshark used so ineffectively coupled with the Allison XT-40 engine. That was a dud of an engine-transmission combination, if ever there was one, though it never failed in the Pogo planes.

 

[swampyankee]

Turbojet engines are much more reliable than piston engines. Indeed, I think that even a 1970's vintage military turbojet, such as the one in the Crusader, had MTBF at least an order of magnitude better than the commercial piston engines during the last gasp of piston-engined airliners. In other words, a pilot is more likely to get home with a single J-75 than with one or posssibly two R-2800 or R-3350.