What if: Mosquito vs P-38

[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.

 

[wuzak]

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.

Greg, we've had this discussion before.

If the 3600hp is a genuine power number I'd suggest it is taken at the prop. It makes little sense to quote power without the supercharger drive power, other than to compare the load that is in the engine.

In any case, how woul dthey measure the power to drive the supercharger?

At what boost/rpm are your engines making 2900hp?

 

[mhuxt]

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.

None of the Canadian Mossies used two-stage engines.

 

[wuzak]

None of the Canadian Mossies used two-stage engines.

One (a MkXXV) was converted, however, in the UK.

There were plans to produce the Mk23 in Canada with two stage engines, but this came to nought.

 

[Shortround6]

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.

The Allison used About a 10% higher compression ratio, while it limited peak boost it should have made for better specific fuel consumption. Other things can factor into the fuel consumption of an engine, especially at different throttle/rpm settings. Please remember that the P-38 was also using the turbo even in many cruise settings and an Allison flown at low rpm and high (relatively) boost would have low friction and low supercharger losses. Exhaust thrust doesn't work so good at cruise because it depends on mass ( weight of fuel and air) and exhaust speed matching the speed of the aircraft, simplified. At cruise settings there is a lot less air mass and the engine has gone from rich to lean settings so their is even less fuel mass. The exhaust gas exit speed is pretty much the same, perhaps a bit lower but the slower aircraft speed makes for a poorer match and the thrust doesn't convert to power as well. Were the Spitfires more frugal at the same airspeed? or at the same throttle settings? or did they cover more ground for the same fuel?

 

[tomo pauk]

Comparison of sinlge-stage Merlins and Allsions is a different metter than a comparison with two-stage versions.
Single stage ones can have a difference in fuel consumption within single digits, for same flight regimes. A two-stage Merlin uses it's engine power to drive both of it's stages, while the V-1710 in P-38 uses the exhaust gasses to drive the 1st stage (the turbo compressor); engine drives only the second (engine-) stage. So for the cruise regime, a two stage Merlin should be using more fuel.
As SR6 noted, the pilot of the 'turbo plane' can use those properties to extract fair amount of power by keeping the manifold pressure high and RPM low. Low RPM means friction losses are low, that also improves mileage.

Thanks for clearing the issue about the two-stage V-1650s for Canadian Mossies, mxhut

 

[zarglink]

As a one on one battle the p38 likely had an edge as all its specs from max speed to rate of climb and payload were higher, (although as for the basic airframe it would be interesting to see the mosquito fitted with the same more powerful engines as the lightning) and for sticklers about low altitude turning radius, it almost doesn't matter. in the pacific the lightnings were avoiding low altitude turning battles anyway. the lightning could dive in at a speed deserving of a mach number, then climb out two or three times faster than its opponent, it would be stupid to stick around and slug it out.

high altitude turning radius is a different matter. i believe (guessing) the mosquito could out turn the lightning at altitude also, but given the engines it would probably bleed speed and lose altitude faster. high ground in a battle wins. makes sense to me that even if you manouevered all the way to the deck down from 30 thousand feet with the lightning in pursuit, the lightning would do best to disengage, climb then finish off with a high speed dive at the retreating mosquito.

whos faster, superman or the flash?

as an aide to the war effort the mosquito was superior, think of something like the sherman tanks vs the panzers. the shermans were horrible but they were soooo much easier to make.
this advantage for the mosquito was because of its wooden construction, and the wood wasnt just a close substitute, it was superior in some regards.
Goring was asked what kind of plane he needed to win and he said he needed mosquitos. Comments were made that every piano, furniture, and cabinet shop in england could make mosquitos with mostly lowly skilled labor to boot. Additionally, here's where wood was superior...mosquitos absorbed hits from flak and bullets extremely well, and upon landing a crew could spackle in holes with epoxy and sawdust/fabric and the things would literally be as strong as new in 24 hours and back out there. tally ho!
in a sense, given the construction strategy of diagonally overlapping direction of the wood grain, the ability of the shell to add strength in both tension and compression, and the use of resin epoxy, they are almost the first composite aircraft ever deployed.
as a side note, if the yanks had actually offered to sell the brits the lightning WITH the superchargers, i wonder if the brits would have bothered to make so many mosquitos or continued development on them.

Those were design choices. Boeing could have made similiar choices when designing the B-17.

BTW, I consider wood construction to be a negative feature. Britain did this because they had a shortage of aluminum not because wood was inheritly superior for aircraft construction.

off with a high speed dive at the retreating mosquito.

whos faster, superman or the flash?

as an overall aide to the war effort the mosquito was superior, think of something like the sherman tanks vs the panzers. the shermans were horrible but they were soooo much easier to make.
this advantage for the mosquito was because of its wooden construction, and the wood wasnt just a close substitute, it was superior in some regards.
Goring was asked what kind of plane he needed to win and he said he needed mosquitos. Comments were made that every piano, furniture, and cabinet shop in england could make mosquitos with mostly lowly skilled labor to boot. Additionally, here's where wood was superior...mosquitos absorbed hits from flak and bullets extremely well, and upon landing a crew could spackle in holes with epoxy and sawdust/fabric and the things would literally be as strong as new in 24 hours and back out there. tally ho!
in a sense, given the strategy of diagonally overlapping direction of the wood grain, the ability of the shell to add strength in both tension and compression, and the use of resin epoxy type glue, they are almost the first composite aircraft ever deployed. a happy accident because of metal shortages.

Those were design choices. Boeing could have made similiar choices when designing the B-17.

BTW, I consider wood construction to be a negative feature. Britain did this because they had a shortage of aluminum not because wood was inheritly superior for aircraft construction.

 

[FLYBOYJ]

Comments were made that every piano, furniture, and cabinet shop in england could make mosquitos with mostly lowly skilled labor to boot. Additionally, here's where wood was superior...mosquitos absorbed hits from flak and bullets extremely well, and upon landing a crew could spackle in holes with epoxy and sawdust/fabric and the things would literally be as strong as new in 24 hours and back out there. tally ho!
in a sense, given the strategy of diagonally overlapping direction of the wood grain, the ability of the shell to add strength in both tension and compression, and the use of resin epoxy type glue, they are almost the first composite aircraft ever deployed. a happy accident because of metal shortages.

Are you making these comments based on what you've read or by actually working with wood aircraft? Your comments sound like you're building your favorite 1/72 scale model! I've worked on wood aircraft (35 years as an AME) and I could tell you wood sucks and is no way as easy to repair as you say. The more repairs you do to it, the more the potential for structural failure. You have to have a clean and temperature controlled environment for some of the glues and resins to really work correctly. Remove a wood aircraft from a moist cool environment and watch the shrinkage! There's a reason why wood aircraft all but disappeared after WW2. Go back through this forum, this subject has been covered extensively. Even in todays world, wood could be a liability.

Plane crash kills 1 during qualifying at Reno Air Races

Lee Behel was not only a great pilot but was a friend. Many of us worried about him and his aircraft.

 

[tomo pauk]

As a one on one battle the p38 likely had an edge as all its specs from max speed to rate of climb and payload were higher, (although as for the basic airframe it would be interesting to see the mosquito fitted with the same more powerful engines as the lightning) and for sticklers about low altitude turning radius, it almost doesn't matter. in the pacific the lightnings were avoiding low altitude turning battles anyway. the lightning could dive in at a speed deserving of a mach number, then climb out two or three times faster than its opponent, it would be stupid to stick around and slug it out.

Welcome to the forum
Some things that I'd kindly disagree here. The payload of the Mosquito was nothing to scoff about, with caveat that most if not all was carried internally. That means that Mosquito is a far better bomber than P-38 in the best iteration. The P-38 was, however, a better fighter.
The dive speed of Mosquito was higher than of P-38, you can check out at this thread where people contributed hard data, not opinions. No ww2 fighter will outclimb another one in zoom climb by factor 2 or 3, granted there are better and not so good zoom climbers.

high altitude turning radius is a different matter. i believe (guessing) the mosquito could out turn the lightning at altitude also, but given the engines it would probably bleed speed and lose altitude faster. high ground in a battle wins. makes sense to me that even if you manouevered all the way to the deck down from 30 thousand feet with the lightning in pursuit, the lightning would do best to disengage, climb then finish off with a high speed dive at the retreating mosquito.

The P-38 have had a slight edge at altitude vs. Mosquitoes with 1-stage supercharged engine. If you disengage vs. Mosquito, you've just let it of the hook. As above - P-38 was a lousy diver (but a good climber), when compared with anything modern (Spitfire, Fw 190, P-51, Bf 109).

as an aide to the war effort the mosquito was superior, think of something like the sherman tanks vs the panzers. the shermans were horrible but they were soooo much easier to make.

Don't fall to the myths, check this out: video.

as a side note, if the yanks had actually offered to sell the brits the lightning WITH the superchargers, i wonder if the brits would have bothered to make so many mosquitos or continued development on them.

Again - don't fall to the myths. The British contracted the Lightning I with one supercharger per engine, and then for Lighting II with 2 superchargers per engine (4 S/C total), later the order was cancelled due to the pricey Lightining I not being as fast as the turboed (and even more pricy) Lightning II. The P-38 could replace Mosquito as a fighter bomber, not as a pure bomber.

 

[GregP]

Hey Joe,

Does you know if anybody really knows yet what happened to Lee and "Sweet Dreams?"

I have heard:

1) Unknown structural failure
2) Wing fluttered and departed the aircraft
3) Failed glue joints
4) Encountered wake turbulence that exceeded the design strength

I was not there at the time, don't really know, and would not care to speculate about an event I didn't see. I DO know Lee and Sweet Dreams broke some time-to-climb records shortly before Reno and have seen a video of the flight as Lee disappears off the top edge of the screen, but never have seen a clip of the race. If nothing else, it surely was a great-looking aircraft.

 

[tyrodtom]

I almost bought a partly completed Pietenpol Sky Scout about 10 years ago. Wood fuselage and wings.
Drove up to Pa. to inspect it, I even took my car trailer with me to bring it back.

It had been stored in a usually unheated garage for about 5 years, it had no fabric on it so I could inspect it pretty well.

Even to my uneducated eyes I could see way too many suspect wood joints. I drove back home with a empty trailer.

Speaking of repairing wood structures. Did they even have epoxy adhesives in the WW2 era ?

 

[FLYBOYJ]

Hey Joe,

Does you know if anybody really knows yet what happened to Lee and "Sweet Dreams?"

I have heard:

1) Unknown structural failure
2) Wing fluttered and departed the aircraft
3) Failed glue joints
4) Encountered wake turbulence that exceeded the design strength

I was not there at the time, don't really know, and would not care to speculate about an event I didn't see. I DO know Lee and Sweet Dreams broke some time-to-climb records shortly before Reno and have seen a video of the flight as Lee disappears off the top edge of the screen, but never have seen a clip of the race. If nothing else, it surely was a great-looking aircraft.

I was there but didn't see the accident but if I had to guess I would say all of the above. He did break some climb records at Mojave earlier in 2014.

 

[GregP]

Thanks. I hadn't heard anything and wondered of someone more in the know had ...

 

[parsifal]

Im late for this party so I apologise for being a bit off centre to the current state of the discussion. I think its impossible to compare the two aircraft outright because they each had vastly different roles. I prefer to look at operational results rather try and argue performance issues. I take the view that if the results are there, the performance had to be there somewhere.

There are limits to what can be done with operational results assessments. For one thing we cant say that the challenges were the same for the two aircraft, mosquito was used principally at night, was used in a somewhat different time frame and in vastly different circumstances. neither can we do much in the way of assessing air victories, since many of the roles for the mossie involved unarmed bombers and claims are just that .

possibly one useful exercise , if admittedly very simplistic is to look at loss rates, since these figures are fully known and allow for the widely varied roles that each type was used.

Looking first at the P-38....
In the ETO, P-38s made 130,000 sorties with a loss of 1.3% overall, comparing favorably with ETO P-51s which posted a 1.1% loss, considering that the P-38s were vastly outnumbered and suffered from poorly thought-out tactics. The majority of the P-38 sorties were made in the period prior to Allied air superiority in Europe when pilots fought against a very determined and skilled enemy. Lieutenant Colonel Mark Hubbard, a vocal critic of the aircraft, rated it the third best Allied fighter in Europe. The Lightning's greatest virtues were long range, heavy payload, high speed, fast climb, and concentrated firepower. The P-38 was a formidable fighter, interceptor and attack aircraft


Now for the Mosquito. in nightime operations over the continent, between 1943 and 1945, it flew 26936 sorties and lost 106 aircraft to combat, a loss rate of 0.33%. no other allied aircraft even came close to that record.

In daylight operations, it flew about 12500 sorties and suffered a losses of 148 a/c at a rate of 1.15%

dangerous to do, but if we combine those day/night operations for the mosquito, we get 39436 sorties, and an overall combat loss of 254 a/c. Overall day/night combat loss rate for the mosquito is 0.64% per sortie.

it was about twice as safe to fly the mosquito in its various roles as it was to fly the p-38 in its various roles, in the ETO.

 

[GregP]

If you're fighting a war, I'm not too sure safety is the primary concern. The primary concern would be combat results on similar missions.

 

[parsifal]

Yes, I can agree with that,, but as the japanese found, crew survivability leads to a lot of other goodies. With survival comes a larger slice of your force structure with the necessary skills to do stuff better, a wider mission profile whereby your aircraft can be expected to do some really gobsmacking stuff, because you know you have a good chance of survival. You can bomb stuff more accurately, attempt more dangerous missions, look at stuff other people cant, remain in fights other aircraft cant, and the list goes on. The operational usage of both the P-38 and the Mosquito suggest both had these qualities. The two types had different backgrounds and development histories.....the mossie was designed as a bomber and recon machine, then had nightfighter added to the mix, then fighter bomber and finally day or night intruder. P-38 started as a fighter then had other roles added to it as time progressed. Both did those other things pretty well, suggesting two very versatile and capable aircraft. I cant see how massive distinction can be made to their respective capabilities, but each of them was born for a completely different purpose in the beginning.