What if: Mosquito vs P-38

[wuzak]

The FBVI didn't enter service until 1943. The FII didn't do much before it became the NFII. And until 1943/44 NFs didn't go into Europe, staying home and defending British airspace.

The Mosquito was much more useful as a bomber, a PR aircraft and a night fighter. As a fighter the P-38 wins hands down, and as a fighter bomber you could probably go either way - remembering that the P-38's range was restricted quite a bit when carrying bombs.

So, what you want to achieve with the aircraft determines the final choice. If you wanted a fighter, go the P-38, but if you wanted a PR, bomber or NF aircraft go teh Mosquito.

[mhuxt]

That’s about 70.1 enemy aircraft per month, and that is WAY better than any Mosquito unit ever achieved.

Assuming you don't want a single Mossie squadron to match the totality of the P-38 force, you'll probably need to moderate that sentence, or define what "WAY better" or "ever" mean, since the Mossie kill rate for all of 1944 was 76.5 per month. From January '44 to the end of the conflict in Europe, the rate was 70.0 per month.

[GregP]

Good post Wuzak, and I can't argue too hard with your statements.

Mbux, you're doing what many others do ... some particular model was introduced at some point and you want to use only the best model and the best missions for your numbers. Sorry, use the series as a whole. I could break down the P-38 by model introduction and theater, too, but that gives a false picture of the total service life of the type.

My own measure of efficiency to the war effort is kills per month over the months of service. I'd MUCH rather have kills per action sortie, but you can't typically FIND that data for all the types you want to compare, so we're stuck with SOMETHING as a measure. You choose yours. I'll use a measure that takes into account for the entire service life of a type and I feel confident in my consculsions.

No doubt we could show that some Mosquio squadron had 5 kills and no losses on some mission and conclude that the Mossie was tops. But that ignores the rest of the service life of the Mosquito, and I find that disingenuous. I suppose we have to agree to disagree on this one. That does NOT mean I dislike the Mosquito; I don't. It means I use a measure that I find to be fair to the early life, the combat service, and the non-action sorties all rolled into one.

On the negative side, it doesn't take into account for the number of aircraft employed. I'd include that, too, but have no source ofr the numbers of P-38's or Mosquitos employed over what period. To get atht data sounds like a 10-year project and though I am interested, I am not interested enough to imterrput my already 15-year project to comile a databse of all WWII types including prototypes. So, I use total kills divided by months of service as a qualitative measure.

Actually, I have a GREAT measure that takes into account for everything (kills, losses, sorties, action sorties, time of service, and number of aircraft built), but you can't find all the data for ANY types as far as I have been able to see. So although it makes a great statistic, it is impractical to use as a qualitative measure. In plain English, my great number is uselsss because the data are almost impossible to obtain for any meaningful portion of all WWII aircraft.

[Vincenzo]

P-38’s were in USAAF service in the ETO from near the end of 1942, and got their first kill in Aug 1942 while being ferried to the ETO. The first ETO kill on an ETO mission was in April 1943. By September 1944, the Lightning was withdrawn for the ETO as a fighter due to a low limitng Mach number of 0.68, though it DID stay on a PR plane. Most Lightnings went to PTO and the low limiting Mach number was fixed with the P-38J. So the P-38 was basically in ETO service for 13 - 14 months and scored 497 kills. That’s 35.5 to 38.2 kills per month of service, counting September 1944, at which time the Lightnings were gone.

The Mosquito entered RAF service in 1941 and served for the entire war thereafter. It served for 4.5 years. Let’s say the Mosquito claimed about 1,700 kills, if the numbers sent to me are corect (I can't say). That’s generally in the same ballpark, at 31.5 kills per month.

So in the ETO, the two were apparently about equally effective.

Overall, in all theaters of USAAF operation, the Lightning was in USAAF service for 4.5 years and shot down 3,785 enemy aircraft. That’s about 70.1 enemy aircraft per month, and that is WAY better than any Mosquito unit ever achieved.

As I said, give me a P-38 any day all day long, unless I needed a bomber for a mission. As a bomber the Mosquito was very probably better, though I'd still take a squadron of P-38's over a squadron of Mosquitos.

your numbers worth nothing

for clear, that numbers worth alone if we have same number of fighters that flying same number of missions that encountered same opposition

[mhuxt]

That's a fair call Greg. So far as I know, the RAF sortie numbers are contained in the Group Summaries, and in the Squadron ORBs. I can find sortie numbers for bomber Mossies of 2, 5 and 8 Groups, and for the 2 Group FBs from late 43 onwards.

IIRC Chris Shores 2nd Tactical Air Force books have sorties (by Wing?) for the night-fighters of 2 TAF, however I don't have monthly summaries for Fighter Command or Coastal Command, though it's possible they appear in various books.

Now that ORBs are available online, it may be possible to build a much better picture, though as the files are currently sold by month, it might be a while before I can access them all. Couple other mini-projects first, namely sorting out the 300-odd V-1 claims not yet in my db, and getting some files about German flak claims.

[GregP]

Fair enough mhuxt. Good luck with your research. Maybe you could post the URl where they are avialable? Appreciate it!

Thanks Vincenzo, I appreciate YOUR numbers just as much as you appreciate mine, although you haven't posted any in here. I have to use SOMETHING, and the data available, particularly for Axis aircraft, are not very easy to dig out. Especially for Soviet aircraft.

I'd bet a large sun of money that my data are more complete than anything you have (being the subject of 15 years research), and it is STILL tough to come up with a fair evalutaion of aircraft.

Only ONE thing is for sure to date: the Me 109 shot down more enemy aircraft in WWII than all other aircraft in all other wars in human history combined. And it is tough to get exact numbers for the Me 109 production build, much less the victories.

[Jabberwocky]

P-38’s were in USAAF service in the ETO from near the end of 1942, and got their first kill in Aug 1942 while being ferried to the ETO. The first ETO kill on an ETO mission was in April 1943.

[SNIP]

The Mosquito entered RAF service in 1941 and served for the entire war thereafter. It served for 4.5 years.

Small correction:

Mosquito first operational fighter sortie (NF Mk II): 27 April 1942

First fighter claim: 30 May 1942

First 'confirmed' fighter kill: 26/27 June 1942

[Southron]

My understanding is that the P-38 was largely replaced in the ETO by P-51's. One of the problems experienced by the P-38's was that their Allison engines did not do all that well in the cold temperatures of Northern Europe, especially at altitude.

Obviously, the USAAF did not think that the P-38 was an adequate night fighter because the P-61 was designed and used for that role.

Actually, I believe that the P-38 never had a chance to reach its true potential as it was equipped with Allison engines. IF the P-38 had been re-equipped with Packard built Rolls Royce Merlin engines, it would have been a much, much more potent fighting machine.

I really wonder how a "fly-off" between a P-38 equipped with Merlin engines and a Mosquito would had have gone.

Keep in mind that the Mustangs were a "so-so" performers until their Allison engines were replaced by Merlins!

[tomo pauk]

The major part of the P-38s problems (actually, the problems of the initial P-38Js) with the V-1710s were duel to pilots using wrong engione settings, the high RPM and low manifold pressure. Because the new intercoolers were more efficient than the old ones, that was leading up to the puddling of the fuel in the intake manifolds, leading to the damaged & destroyed engines. With engines operated as 'ordered' both by Lockheed and Allison (low RPM, high manifold pressure), the air-fuel mixture was of right temperature and the engines were far less likely to be damaged.

Why do you think that a later plane (P-38M) could influence anything regarding the earlier plane (P-61)? Perhaps it was the other way around - the USAAF was not very happy with P-61, so they decided to go with a P-38 modification?

If you want to compare engines, I'd advice that you 1st try to read more about Merlins and Allisons. And then compare likes with likes. For the starters, you might want to compare the P-40s, planes that were fitted with both Allisons & Merlins. Then, you might try to get yourself a nice book, called the 'America's hundred thousands' by Francis Dean. Worth every penny, it might be even cheaper for you in the USA than it was for me in Croatia

[Shortround6]

Tomo is for the most part correct. What he has posted was a large part of the problem. Another part was that the allowable components of the 100/130 fuel were changed with more "heavy" Compounds being allowed. This contributed to the fuel puddling problem to the extent that Allison was working on a new intake manifold in the summer of 1943 that was to be fitted to ALL types of Allison engines and by Nov/Dec 43 shipments of new manifolds were being sent overseas for the refitting of ALL Allison engines regardless of airframe type.
There were at least 5 contributing factors to the P-38 problem to greater or lesser degrees which is why it took a while to sort it out. Unfortunately for the P-38s reputation it was sorted out with in a couple of weeks of the decision to concentrate on the P-51. The P-51 was the better choice but it was not quite the obvious choice it is sometimes made out to be.

Another rather interesting book is "Vee's for Victory" which is the story of the Allison engine. It goes over 3 different paper studies to use Merlin's in place of Allisons. In some cases the Merlin's offer better performance in some parts of the performance envelope. But they were usually figured to give less range. In one instance ( depending on particular model of which engine and exact cruise conditions) the difference was estimated to be a loss of 30% in range with the Merlin. Most of the time the differences were estimated to be in the single digits percentage wise.

[tomo pauk]

Thanks for further insight

One issue remains for all of those Merlin P-38 advocates to clear is: who is going to produce all those engines needed? Unlike the Allison, Packard was not in position to provide any meaningful surplus of the engines. For any 1 P-38 to fly with two stage Merlins, that would mean 2 P-51B/C/D/K less - bad thing for Allied war effort.

[pbfoot]

Thanks for further insight

One issue remains for all of those Merlin P-38 advocates to clear is: who is going to produce all those engines needed? Unlike the Allison, Packard was not in position to provide any meaningful surplus of the engines. For any 1 P-38 to fly with two stage Merlins, that would mean 2 P-51B/C/D/K less - bad thing for Allied war effort.

Or the Lancs, Mossies and Hurricanes made in the Great White North

[tomo pauk]

The Hurri was using single stage engines exclusively, though. For the Lancs and Mossies form Canada we could use some good data about usage of both single- and two-stage variants.
Some two-stage Packard Merlins were also used in Spitifires, in the Mk.XVI. Beaufighters and Lancs from the UK also using the US-built Merlins.

[GregP]

Southron, you could not be more wrong. The Allison engine is very reliable and strong. It holds a tune MUCH lionger than a Merlin. The first units over had some intake issues becasue they were deployed before being completly tested. It also took us some time to realize that European gasoline is fundamentally differnt from American gasoline. The aromatics are WAY different. 4% versus 12 - 20%.

The P-38 only served about 13 months in Europe, but was fixed about the time it departed for the Pacific, and fixed for both American and Europen fuel ... and the intake issue, too. It COULD have remained, but the P-51 was then in Europe and proved a great long-range escort. You might recall that the two top American Aces flew P-38's in the Pacific.

To this day, the Allison is whipping Merlins in tractor pulls all over Europe. Our Allisons (I work at a shop that builds Allisons) regularly get 900 - 1200+ hours between overhauls, and that is a LOT longer than WWII USAAF TBO. I don't know ANY Merlin operator getting that kind of service from his or her Merlin, Packard OR Rolls-Royce. All of the P-38's in the world except the Red Bull unit are running our engines and doing quite well, as are various Yaks, P-39's, P-63's and the odd MiG-3. The Red Bull P-38 may well be doing the same in the near future, if they want to keep flying it!

Even the Reno race-winning Merlins are using Allison G-6 rods to get the power because the stock Merlin rods won't handle 3500 HP but the Allison rods will. We want to field a race winning Allison 1710, but need someone to pony up and supply an airframe. If they do, we can deliver a race winning Allison V-1710. So far, nobody has wanted to race one ... but we're ready if they do. We can deiver about 2900 HP to the prop from a 1710 or about 5,000 HP from a W-3420. We have one W-3420 and about 100 V-1710 engines, including E, F and G series Allisons avilable.

The 3600 HP Merlins don't deliver that to the prop because they need to supply about 600 - 800 HP for the supercharger. So technically, they also deliver about 2900 HP to the prop.

[Jabberwocky]

But they were usually figured to give less range. In one instance ( depending on particular model of which engine and exact cruise conditions) the difference was estimated to be a loss of 30% in range with the Merlin. Most of the time the differences were estimated to be in the single digits percentage wise.

Interesting.

There is a USAAF document about aircraft maintenance, either from Nth Africa or Italy, that has average fuel consumption per hour figures for the P-40, in both V1650 and V1710 powered guises, as well as for other fighters.

From what I can recall (Home PC died recently, so I can't get to it at the moment) the Merlin actually had marginally lower fuel consumption than the Allison. The Spitfires in USAAF service were also notably more frugal than the P-40s with Merlin engines.