Reliability of WW2 fighters.

[marshall]

I'm interested in how reliable were WW2 fighters but I couldn't find any good info about it. Which one was the most reliable fighter and which one was the least? By reliable I mean everything engine, guns, airframe, how much work it took on the ground to get it ready to fly, how much beating it could take in the air, etc.
How do you guys think it was with this reliability?

[Sgt. Pappy]

Depending on the theater of war, the aircraft could be of different reliability.

In England, the Spitfire was relatively to repair - the Hurricane was even easier. The small, simple, single-engines fighters were at the top of their game in the Battle of Britain and were doing well. When they were shipped overseas to the likes of the Mediterranean, China-Burma-India and Pacific Theaters of War, they experienced many problems... fouled oil/fuel lines, faster engine break-down rates due to sand etc. After all, they were designed for nice, English weather.


Also, it's not just the era that determines reliability.

I.e. Some may argue that the P-47 Thunderbolt was far more reliable than the much more recent F-14 in terms of engine break-down rates.

It is widely believed that a radial engine aircraft is more reliable and is easier to fix than an aircraft with an inline engine. The Corsair was powered by a radial, Pratt & Whitney R-2800 18-cylinder engine that was air cooled.

The Spitfire was powered by an inline 12-cylinder, Rolls-Royce Merlin that was liquid cooled. The arrangement of their cylinders necessitated their respective cooling methods. Thus, the Spitfire mechanics had to tinker with coolant lines and radiators and the Corsair mechanics did not. Also, the glycol used to cool the Spit's engine was highly flammable... not so good in combat. But the Spitfire wasn't designed to take hits... rather to dodge them.

[magnocain]

Over half the Spectres' regular armed combat destructiveness comes from shrapnel.... Where the shrapnel gonna come from with those pretty little twinkling lasers??

I agree. I dont think water-cooled, inline engines can even be called "easy mantinance".

Over half the Spectres' regular armed combat destructiveness comes from shrapnel.... Where the shrapnel gonna come from with those pretty little twinkling lasers??

Wasn't the f-14 taken out of service because it was hard to maintain?

[Crumpp]

All of them have very similar TBO's.

The BMW801 for example requires "overhaul" at 200 hours. This could be done 5 times before the motor had to be sent to depot maintenance for rebuild.

"Overhaul" consists of changing oil, clean oil screen/filter, fuel filter change, vacuum system filters, checking compressions, clean/replace plugs as needed, and inspect/repair as needed.

All the best,

Crumpp

[marshall]

So how often an engine could break-down during a flight? I mean was it 1 per 100 flights of a given type of plane or maybe more like 1 per 1000 or 1 per 10000 flights?

How often guns jammed? I heard that 20mm cannons were less reliable than machine guns, is this true?

Were there planes, on both sides, that were considered to be very reliable or maybe there were some planes that had a bad reputation in this matter?

[FLYBOYJ]

Originally Posted by magnocain

Wasn't the f-14 taken out of service because it was hard to maintain?

I knew guys who worked on the F-14 - according to them, compared to the F/A-18 it was a pain in the @ss.

As far as the F-14s retirement - I think it was more or a matter of operational costs compared to newer aircraft that could do the same job - F/A-18.

As far as WW2 - radials over in-line, definitely! I read that engine changes could be as early as 25 hours and as high as 500 hours. Be advised that on all sides during the war you had a lot of "expressed trained" pilots who often abused engines by running them too rich or lean or at the wrong MP settings.

Systems wise I think they were all similar. I read on here somewhere a story about the Manchester with some less than desirable airframe systems.

BTW - my family recently attained an accident report from my wife's grandfather, a B-24 pilot with the 7th AF. Shortly after the war he was on a training mission and while taxiing out his aircraft suffered a MLG collapse. The aircraft had 1,200 hours on it, in aircraft age especially for a large multi-engine aircraft, that's not a lot of time.

I think the ruggedness of most WW2 combat aircraft made them reliable but at the same time many of them were also designed with the mindset that the said aircraft may only last 10 hours in combat.

[Crumpp]

This might help. This is the CONUS figures during the war. What is interesting is the fact this the maintenance required for normal operations. No combat is involved.

You can see that a considerable number of the engines simply became scrap with no hope of overhaul or repair:

http://afhra.maxwell.af.mil/aafsd/aafsd_pdf/t113.pdf

Airframes, generally airframes are pretty resilient and it takes quite a bit to turn them to scrap.

http://afhra.maxwell.af.mil/aafsd/aafsd_pdf/t112.pdf

This breaks down the man-hours spent on specific engines. There is not much to choose from as all aircraft engines operate at 100% capacity and above. No matter which engine you choose, they are all being very stressed just by the fact they are an airplane engine. Power to weight is the most important airplane engine characteristic. Maximum power means very little if the power to weight is not within a certain range. Many early aviation pioneers made this mistake when attempting heavier than air flight. They went for the most powerful engine available instead of the engine that produces the most power per unit of weight.

http://afhra.maxwell.af.mil/aafsd/aa...t114and115.pdf

All the best,

Crumpp

[Thorlifter]

Probably the least reliable was the Me-262. If memory serves, the engines were only good for about 12 hours of service, then had to be replaced.

[szczezne]

You have to remeber thay it was the first jet in serwice and they were trying to fix many things and also were learning how to fight with it. This was the end of war and things wer not going good for Germany at that point

[Crumpp]

Probably the least reliable was the

I would say the Pratt and Whitney R-2800 series was the least reliable engine ever designed.

At least according to the team that built it:

http://www.enginehistory.org/NoShort...Crankshaft.pdf

However it was developed into a reliable aircraft powerplant by the start of the war and went on to join aviation folklore.

All the best,

Crumpp

[drgondog]

Originally Posted by Crumpp

This might help. This is the CONUS figures during the war. What is interesting is the fact this the maintenance required for normal operations. No combat is involved.

You can see that a considerable number of the engines simply became scrap with no hope of overhaul or repair:

http://afhra.maxwell.af.mil/aafsd/aafsd_pdf/t113.pdf

Airframes, generally airframes are pretty resilient and it takes quite a bit to turn them to scrap.

http://afhra.maxwell.af.mil/aafsd/aafsd_pdf/t112.pdf

This breaks down the man-hours spent on specific engines. There is not much to choose from as all aircraft engines operate at 100% capacity and above. No matter which engine you choose, they are all being very stressed just by the fact they are an airplane engine. Power to weight is the most important airplane engine characteristic. Maximum power means very little if the power to weight is not within a certain range. Many early aviation pioneers made this mistake when attempting heavier than air flight. They went for the most powerful engine available instead of the engine that produces the most power per unit of weight.

http://afhra.maxwell.af.mil/aafsd/aa...t114and115.pdf

All the best,

Crumpp

Great stuff.

I found one reference in 355th microfilm to a 357FS P-51B-7 that was declared WW and subsequently used only as a hack after 640 airframe hours and two engine changes.. theoretically the highest hour airframe in the 355th FG. This was in October 1944 - for a Mustang that was in the original complement in March.

[Thorlifter]

Originally Posted by Crumpp

I would say the Pratt and Whitney R-2800 series was the least reliable engine ever designed.

I tried to read the article, but my ADD kicked in and I started arguing with a dust ball.

But I did read the conclusion and it was practically nothing but praise for the engine.

[Crumpp]

But I did read the conclusion and it was practically nothing but praise for the engine.

And rightfully so, once it was a developed engine. The article is about the difficulties experienced in that development.

Facts are all engines start off "unreliable" especially in the days of the slide rule. They are then developed into reliable power plants.

No different than the BMW 801, Merlin series, or any other aircraft engine.

No if you compare the man hours in maintenance for the R-2800 to any other engine you will get a more complete picture.

I found one reference in 355th microfilm to a 357FS P-51B-7 that was declared WW and subsequently used only as a hack after 640 airframe hours and two engine changes.. theoretically the highest hour airframe in the 355th FG. This was in October 1944 - for a Mustang that was in the original complement in March.

Interesting stuff, Bill! Thanks for posting that.

For the readers, the times are ridiculously low in combat with too many "unknowns" to quantify a good picture of reliability from a maintenance standpoint.

Happy Holidays!

Crumpp

[drgondog]

Originally Posted by Crumpp

I would say the Pratt and Whitney R-2800 series was the least reliable engine ever designed.

At least according to the team that built it:

http://www.enginehistory.org/NoShort...Crankshaft.pdf

However it was developed into a reliable aircraft powerplant by the start of the war and went on to join aviation folklore.

All the best,

Crumpp

Gene - I think you are dead on not just for every new design - but also for major evolutionary step - whether Rolls, BMW, DB, Pratt or Allison. A lot of airframes (i.e B-29) were delayed because of major engine gestation issues..

[marshall]

So generally, can we say that WW2 fighters were very similar in terms of reliability and the newer the type/model the less reliable it was but with time it was geting better and better of course in terms of reliability? There was no planes with bad reputation?

One more question, was it often that someone was on a sortie and suddenly engine is dead, broken, and he becomes a glider? But not because of enemy fire just because engine broke.