What if the P-38 was made of plywood a la Mosquito?

[Fighterguy]

Well, from my understanding, the Mosquito used plywood (which is a composite, the grandfather of modern carbon fiber) so it wouldn't stress strategic resources. The British air ministry wasn't keen on the idea, so De Havilland had to think outside the box to develop the aircraft on their own. Using wood was an alternative that worked better than anticipated. These factors weren't present during P-38, or any other American aircraft outside the Spruce Goose, during design and production. Innovation is driven by circumstance. Where the Mosquito saves weight, is mostly in the frame, spars, ribs, stringers, longerons, and bulkheads, coupled with the use of adhesives, versus rivets, screws, and bolts. The P-38, if made using wood, may have been lighter, but there's no way to know if that alone would've significantly improved performance. Someone would have to use computer modeling to test the theory.

 

[Macandy]

Couple of points.....

A Mosquito designed in metal would have been lighter and better - at the time it was designed, the UK thought it would run short of aluminium.

You can calculate the strength and load factors in a metal airframe to a very fine degree. Wood is a variable material. Every piece is different, so you have to build in excess material to cover that.
But once the structure is compromised, it's quickly all but impossible to calculate the residual strength and ascertain wether the airframe is still fit for service.
You can take a Chance 'it Should still be alright' in wartime, but killing pilots is frowned upon once peace breaks out.
The RAFs mosquitos had led a hard life exposed all their lives to the elements.

Faced with the risks of non calculable airframe degradation, the RAF opted not to take the risk and gave most Mosquitos a petrol bath and a match as soon as the war ended.

 

[Kevin J]

Couple of points.....

A Mosquito designed in metal would have been lighter and better - at the time it was designed, the UK thought it would run short of aluminium.

You can calculate the strength and load factors in a metal airframe to a very fine degree. Wood is a variable material. Every piece is different, so you have to build in excess material to cover that.
But once the structure is compromised, it's quickly all but impossible to calculate the residual strength and ascertain wether the airframe is still fit for service.
You can take a Chance 'it Should still be alright' in wartime, but killing pilots is frowned upon once peace breaks out.
The RAFs mosquitos had led a hard life exposed all their lives to the elements.

Faced with the risks of non calculable airframe degradation, the RAF opted not to take the risk and gave most Mosquitos a petrol bath and a match as soon as the war ended.

As an example of produced: victories. Yak-1/7, 15100; 10 pilots got 8 or more aerial victories. Hurricane IIb/c, 2600 in USSR, 3 pilots got 8 or victories. Yak superior fighter to Hurricane. Hurricane still in use in 1944 in PVO. Twice as cost effective by numbers, don't know about price. I doubt if those Yaks lasted more than a year though with the extreme weather conditions on the Eastern Front.

 

[pbehn]

Couple of points.....

A Mosquito designed in metal would have been lighter and better - at the time it was designed, the UK thought it would run short of aluminium.

You can calculate the strength and load factors in a metal airframe to a very fine degree. Wood is a variable material. Every piece is different, so you have to build in excess material to cover that.
But once the structure is compromised, it's quickly all but impossible to calculate the residual strength and ascertain wether the airframe is still fit for service.
You can take a Chance 'it Should still be alright' in wartime, but killing pilots is frowned upon once peace breaks out.
The RAFs mosquitos had led a hard life exposed all their lives to the elements.

Faced with the risks of non calculable airframe degradation, the RAF opted not to take the risk and gave most Mosquitos a petrol bath and a match as soon as the war ended.

The Mosquito was produced until 1950 and used until the mid 1950s, post war the equally wooden Hornet was brought into service.

 

[Macandy]

The Mosquito was produced until 1950 and used until the mid 1950s, post war the equally wooden Hornet was brought into service.

Most wartime Mosquitos were very much showing signs of wear by VE Day, the ones in the Far East on VJ Day more so.
They went on to the 'don't waste any efforts fixing these up' list and most were demolished in short order. The RAF had plenty of new ones in storage.
Post war, they could be cosseted and covered or stored in hangers to spare them the worst of the weather, a luxury wartime Mosquitos never had. The Mosquito was rapidly replaced by the Canberra in the bomber role, and Meteor in the Night Fighter role.

 

[Fighterguy]

The Mosquito is significant in the innovative repurposing of available materials and processes to manufacture a weapons platform that was highly effective and successful, while at the same time, reducing demand on scarce strategic resources. It's a means to an end. The fact that it doesn't last long is immaterial after serving its purpose.

 

[pbehn]

Most wartime Mosquitos were very much showing signs of wear by VE Day, the ones in the Far East on VJ Day more so.
They went on to the 'don't waste any efforts fixing these up' list and most were demolished in short order. The RAF had plenty of new ones in storage.
Post war, they could be cosseted and covered or stored in hangers to spare them the worst of the weather, a luxury wartime Mosquitos never had. The Mosquito was rapidly replaced by the Canberra in the bomber role, and Meteor in the Night Fighter role.

Only if you call ten years rapid, the Mosquito was only in the war 4 years. As far as aircraft being scrapped goes, the same goes for almost every type in service with anyone at the end of the war. No wartime aircraft lasted long, F-Freddy completed the most sorties of any allied bomber 213 sorties in two years.

 

[Shortround6]

Using wood was an alternative that worked better than anticipated. These factors weren't present during P-38, or any other American aircraft outside the Spruce Goose, during design and production. Innovation is driven by circumstance. Where the Mosquito saves weight, is mostly in the frame, spars, ribs, stringers, longerons, and bulkheads, coupled with the use of adhesives, versus rivets, screws, and bolts.

There were a few other wooden American aircraft. However without a lot of experience (and some innovation) a wooden airframe has trouble competing with a metal one on a strength for weight basis. We have very few designs where they tried to actually build the same airplane (or at least the same shape) out of wood and aluminum.

The Mosquito was never designed to pull the same G loadings as the P-38, if had been designed for 8 G service load and 12 Gs ultimate (safety factor) it's structure would have been much heavier. It did have a much smoother surface finish which cut drag.

Differences in shape and size also come into play. A thicker wing is stronger than a thinner wing if the material thicknesses are the same. This is for actual thickness, not aerodynamic thickness where the thickness is a percentage of the cord. When pulling Gs you are trying to compress the upper surface of the wing more (and stretch the underside more) on a thick wing than on a thin wing (assuming otherwise similar size and shape) and the thick wing can actually be lighter (requires lighter main spar/s and bracing) .

The Nakajima Ki-106 is one of the few aircraft where they tried to substitute a wooden structure for a metal one (a less strategic material Ki-84) and keep pretty much the same exterior shape/size (tail was bigger)
Sources differ as to if the plane was all wood or just wood fuselage. All agree the plane was heavier with one book claiming a 600lb difference. Perhaps there was difference in the 3 prototypes?

Bell and Curtiss both made a hash out of their attempts at wooden aircraft. It is not as easy as DH made it appear.
.

 

[pbehn]

The Mosquito was a light weight design for a bomber because you couldn't walk down the fuselage and had no turrets or defensive guns as much as because it was made of wood. De Havilland built wooden aircraft before the Mosquito some of which are still airworthy it also used wood for the Hornet as a material of choice and continued to use wood in places on its jets.

 

[wuzak]

Only if you call ten years rapid, the Mosquito was only in the war 4 years. As far as aircraft being scrapped goes, the same goes for almost every type in service with anyone at the end of the war. No wartime aircraft lasted long, F-Freddy completed the most sorties of any allied bomber 213 sorties in two years.

The last Mosquito retired from RAF service in 1963. It was a target tug.

 

[wuzak]

Most wartime Mosquitos were very much showing signs of wear by VE Day, the ones in the Far East on VJ Day more so.
They went on to the 'don't waste any efforts fixing these up' list and most were demolished in short order. The RAF had plenty of new ones in storage.
Post war, they could be cosseted and covered or stored in hangers to spare them the worst of the weather, a luxury wartime Mosquitos never had. The Mosquito was rapidly replaced by the Canberra in the bomber role, and Meteor in the Night Fighter role.

Most Mosquitoes showing wear by VE day had, most likely, completed a lot of missions/hours.

It makes sense to dispose of war weary aircraft in favour of factory fresh ones, particularly those of later marks with improved performance.

As for being replaced with the Canberra and Meteor, they were later, much higher performance aircraft. However:

The Canberra entered service in 1951.

The first PR Meteor flew in 1950. The first NF Meteors entered service in 1951.

 

[wuzak]

Well, from my understanding, the Mosquito used plywood (which is a composite, the grandfather of modern carbon fiber) so it wouldn't stress strategic resources.

The Mosquito's structure was composite in that it had a lightweight core (balsa) with plywood skinning top and bottom.

 

[Macandy]

Most Mosquitoes showing wear by VE day had, most likely, completed a lot of missions/hours.

It makes sense to dispose of war weary aircraft in favour of factory fresh ones, particularly those of later marks with improved performance.

As for being replaced with the Canberra and Meteor, they were later, much higher performance aircraft. However:

The Canberra entered service in 1951.

The first PR Meteor flew in 1950. The first NF Meteors entered service in 1951.

Barely 1000 Mosquitos built post war, and as soon as the jets turned up, even those were very quickly gone from front line service.
Wood was an historical anomaly, not a wonderful design innovation. The Mosquito would have been a better plane if all metal. While DH continued to use wood, it didn't produce durable aircraft.

 

[Glider]

Most wartime Mosquitos were very much showing signs of wear by VE Day, the ones in the Far East on VJ Day more so.
They went on to the 'don't waste any efforts fixing these up' list and most were demolished in short order. The RAF had plenty of new ones in storage.
Post war, they could be cosseted and covered or stored in hangers to spare them the worst of the weather, a luxury wartime Mosquitos never had. The Mosquito was rapidly replaced by the Canberra in the bomber role, and Meteor in the Night Fighter role.

All front line aircraft of all types, of all nations had a 'tough life' during the war and few if any served for any period after the war. The ones that did were invariably aircraft that were newbuilds as there was no need to use worn aircraft, even if the types had been used.
Also technology was moving at prodigious speed and WW2 types were often seen as being outdated in the near future a good example being RAF fighters where the future was recognised as being jet powered

 

[pbehn]

Barely 1000 Mosquitos built post war, and as soon as the jets turned up, even those were very quickly gone from front line service.
Wood was an historical anomaly, not a wonderful design innovation. The Mosquito would have been a better plane if all metal. While DH continued to use wood, it didn't produce durable aircraft.

1000 is a lot to build of a 1941 design in the post war era.

 

[Macandy]

1000 is a lot to build of a 1941 design in the post war era.

Just a reflection of the poor state of Britains aircraft industry at the time.

 

[wuzak]

1000 is a lot to build of a 1941 design in the post war era.

There were ~ 1,300 Canberras made, including 400 in the US and 49 in Australia.

Nearly 4,000 Meteors were built, but I am having trouble finding out over what period.

 

[wuzak]

There were ~ 1,300 Canberras made, including 400 in the US and 49 in Australia.

Nearly 4,000 Meteors were built, but I am having trouble finding out over what period.

Meteor production finished in May 1955.

 

[swampyankee]

I suspect that had the P-38 been designed in wood -- had the USAAF accepted it (wood was not considered an acceptable structural material for aircraft being used to transport passengers or cargo for hire due to multiple structural failures; wooden construction was not permitted for airliners by the CAA. This means it's quite likely that the USAAF would not allow Lockheed or any other manufacturer to build a top-end fighter from wood) -- it would not be built in the twin-boom configuration chosen. It may be possible to design the outer wing panels in wood, but there would be quite severe trade-offs.

 

[pbehn]

I do like the notion that using metal was the trouble free option. All sorts of lessons had to be learned about fatigue and stress corrosion.