# P 51 Mustang vs Mosquito?



## Blitzrockie (Jul 19, 2016)

P 51 vs Mosquito?
If these planes were engage each other who would win?


----------



## Blitzrockie (Jul 19, 2016)

Which airplane is better You can decide


----------



## pbehn (Jul 19, 2016)

In daylight the P51 at night the Mosquito


----------



## Thorlifter (Jul 19, 2016)

Not really an apples to apples comparison, but I agree with Pbehn.


----------



## pbehn (Jul 19, 2016)

Thorlifter said:


> Not really an apples to apples comparison, but I agree with Pbehn.


There were good few missions where Mustangs escorted Mosquitos which kinda answers it.


----------



## DerAdlerIstGelandet (Jul 19, 2016)

Apples to oranges I would think...


----------



## Thorlifter (Jul 19, 2016)

Apples to Zucchini I think! OK, maybe not that far.

If you want to compare the Mosquito to something, compare it to something similar, like another 2 engine plane that served similar roles. The P-38 or Bf-110 just to name a couple.


----------



## FLYBOYJ (Jul 19, 2016)

Blitzrockie said:


> P 51 vs Mosquito?
> If these planes were engage each other who would win?


Who's flying?


----------



## Airframes (Jul 19, 2016)

Galland is flying the P-51, and Reginald Molehusband (ret'd) is flying the Mossie PR4 ...................................

Reactions: Funny Funny:
1 | Like List reactions


----------



## Blitzrockie (Jul 19, 2016)

I do agree that the Mustang was a day fighter and the Mosquito was a night flyer but Mosquitos can't go into a tropical climate, they break down midair.So a Mustang just can't operate at night, Mosquitos can't be in a tropical climate.


----------



## Blitzrockie (Jul 19, 2016)

An Mosquito can't go into a tropical climate because it's not good for the wood that they are made of.


----------



## pbehn (Jul 19, 2016)

Blitzrockie said:


> An Mosquito can't go into a tropical climate because it's not good for the wood that they are made of.


I think that is largely myth, from memory it was a problem with adhesives not the actual wood.

Reactions: Like Like:
1 | Like List reactions


----------



## pbehn (Jul 19, 2016)

Blitzrockie said:


> I do agree that the Mustang was a day fighter and the Mosquito was a night flyer but Mosquitos can't go into a tropical climate, they break down midair.So a Mustang just can't operate at night, Mosquitos can't be in a tropical climate.


The mosquito was a bomber, fighter bomber PR and night fighter. I read one account where a bomber variant evaded a FW 19by going into a shallow dive, at high speed the mosquito had more control and the FW couldnt get a shot in and eventually the mosquito cruised away.


----------



## Airframes (Jul 19, 2016)

Yep, the adhesive used on the Mosquito was, at first, unsuited to high humidity areas, but they *DID NOT* 'break down mid air', or fall apart, or suffer any other serious defect, other than some 'mould' and slight delamination in some areas , within the adhesive.
This was very soon cured, in production, by a change of adhesive formula, and Mosquitos _continued _to operate in the Far East until long after WW2.
As has been hinted at, comparing a Mustang with a Mosquito is like comparing apples to oranges - two very different types of aircraft, with differing, although sometimes complimentary, roles.

Reactions: Agree Agree:
1 | Like List reactions


----------



## chuter (Jul 23, 2016)

Oddly enough, according to Lee Atwood of North American Aviation these are the only two significant aircraft of WW2 that had properly designed and fully functional use of Meredith Effect cooling systems.


----------



## fastmongrel (Jul 23, 2016)

Blitzrockie said:


> I do agree that the Mustang was a day fighter and the Mosquito was a night flyer but Mosquitos can't go into a tropical climate, they break down midair.So a Mustang just can't operate at night, Mosquitos can't be in a tropical climate.



Mustangs could and did operate at night. RAF tactical recon Mustangs I and IA (the ones with Allison engines) operated in all weathers and late into the night. Basically if it can fly and can land it can do it at night as well as day.

The Mosquito falling apart in the East myth will not die even when burnt alive by the truth. The RAAF and RAF both used them very succesfully in the East and the RAF still had some flying as target tugs out of Singapore as late as the early 1950s.


----------



## FLYBOYJ (Jul 23, 2016)

Here we go again...

Wood structures are hard to maintain and are susceptible to swelling and shrinkage depending on climate and environment, in in my broken record stamen - I know this from experience!!! They are harder to repair and inspect and when they fail structurally, it could be catastrophic, even today.

Pilot Lee Behel Killed At Reno Air Races In One-Of-A-Kind Aircraft

A wood combat aircraft will be essentially a "throw away" weapon and although some were around into the mid 50s (IAF used them till 1957 and those were later models), many post war operators probably with the exception of the IAF roles placed minimum stress on the airframes (target tugs).

When one discusses this, look at when these post war Mosquitoes were built, where they were operated and for how long. The IAF had issues with them.

the mosquito in israeli service


----------



## fastmongrel (Jul 23, 2016)

FLYBOYJ said:


> When one discusses this, look at when these post war Mosquitoes were built, where they were operated and for how long. The IAF had issues with them.
> 
> the mosquito in israeli service



The Israeli Mossies were 3rd hand when the Israelis got hold of them they had had a hard life already. The FBIV s had been used by the RAF then refurbished and sold to the French who used them against the Viet Minh who then sold them to the Israelis who used them until 1956. When they would have been at least 11 years old. Not bad for an aircraft that DeHavilland only expected to last 6 months or so.

[2.0] Mosquito In Service / Foreign Users


----------



## FLYBOYJ (Jul 23, 2016)

fastmongrel said:


> The Israeli Mossies were 3rd hand when the Israelis got hold of them they had had a hard life already. The FBIV s had been used by the RAF then refurbished and sold to the French who used them against the Viet Minh who then sold them to the Israelis who used them until 1956. When they would have been at least 11 years old. Not bad for an aircraft that DeHavilland only expected to last 6 months or so.
> 
> [2.0] Mosquito In Service / Foreign Users



The Mosquito was an excellent aircraft, but these were the exception and they still had issues.

_"The Mk. VI was also involved in a large number of accidents which resulted in 14 Mosquito crew fatalities. On August 8th 1953 a Mosquito was lost during night bombing practice, the pilot apparently suffering from vertigo and crashing into the Mediterranean. Another Mosquito was lost the following day when it hit the sea during the search for the first missing Mosquito. The crashed aircraft were only located in the late 1990s. *The accidents usually resulted from poor maintenance of the aircraft,* as well as from the havoc wrecked by the Mediterranean weather."_


----------



## pbehn (Jul 23, 2016)

FLYBOYJ said:


> The Mosquito was an excellent aircraft, but these were the exception and they still had issues.
> 
> _"The Mk. VI was also involved in a large number of accidents which resulted in 14 Mosquito crew fatalities. On August 8th 1953 a Mosquito was lost during night bombing practice, the pilot apparently suffering from vertigo and crashing into the Mediterranean. Another Mosquito was lost the following day when it hit the sea during the search for the first missing Mosquito. The crashed aircraft were only located in the late 1990s. *The accidents usually resulted from poor maintenance of the aircraft,* as well as from the havoc wrecked by the Mediterranean weather.
> 
> ...


Wooden structures may be harder to maintain but the Mosquito was a WW2 combat aircraft, how many ww2 aircraft in front line service had an engine(s) with 2 major overhauls? The record for bomber missions was a mosquito F Freddie with 213 missions. Personally, as a Brit. I dont mind people advancing the argument while saying it is a combination of temperature and humidity, simply saying humidity is ridiculous, in the UK we spend so much time in the rain some of us have webbed feet, Never order soup while sat outside in the UK it may take you a week to finish it.

Poor maintenance cannot be the fault of the aircraft, I dont know how you can establish a cause of crash as poor maintenance when the one crash mentioned specifically states pilot error and the second aircraft is reported as hitting the sea looking for it..


----------



## pbehn (Jul 23, 2016)

chuter said:


> Oddly enough, according to Lee Atwood of North American Aviation these are the only two significant aircraft of WW2 that had properly designed and fully functional use of Meredith Effect cooling systems.


I have never read anything about the meredith effect that discussed the mosquito, I found a long discussion about the Hornet and the main concern was disturbing the airflow under the wing. Would it be more accurate to say they had the best low drag solutions to cooling water cooled engines


----------



## chuter (Jul 23, 2016)

Back in high school I always hated having to do the extra work to stay on top of my wood prop and spars (7AC-65) while my buddy only had to look for corrosion (Luscombe 8a) occasionally (dammit, he was lazy!). I haven't bothered with wood anything since, although I wood be willing to try a vintage Aeroprop automatic propeller with wood blades ... those are really cool - i think, anyway.


----------



## FLYBOYJ (Jul 23, 2016)

FLYBOYJ said:


> It isn't, but these were the exception and they still had issues.
> 
> _"The Mk. VI was also involved in a large number of accidents which resulted in 14 Mosquito crew fatalities. On August 8th 1953 a Mosquito was lost during night bombing practice, the pilot apparently suffering from vertigo and crashing into the Mediterranean. Another Mosquito was lost the following day when it hit the sea during the search for the first missing Mosquito. The crashed aircraft were only located in the late 1990s. *The accidents usually resulted from poor maintenance of the aircraft,* as well as from the havoc wrecked by the Mediterranean weather."_





pbehn said:


> Wooden structures may be harder to maintain but the Mosquito was a WW2 combat aircraft, how many ww2 aircraft in front line service had an engine(s) with 2 major overhauls? The record for bomber missions was a mosquito F Freddie with 213 missions. Personally, as a Brit. I dont mind people advancing the argument while saying it is a combination of temperature and humidity, simply saying humidity is ridiculous, in the UK we spend so much time in the rain some of us have webbed feet, Never order soup while sat outside in the UK it may take you a week to finish it.
> 
> Poor maintenance cannot be the fault of the aircraft, I dont know how you can establish a cause of crash as poor maintenance when the one crash mentioned specifically states pilot error and the second aircraft is reported as hitting the sea looking for it..



Read my first post - "Wood structures are hard to maintain and are susceptible to swelling and shrinkage depending on climate and environment," and I'll further elaborate, temperature - the cool humidity is actually good for wooden aircraft, don't move them to the desert.

You mention some combat exploits - agree, the Mosquito was a great aircraft.

The "poor maintenance" quote was taken from one article, I know there are other articles stating the maintenance challenges of the IAF operating the Mosquito.

In the bigger picture, if wood was so good to use for military aircraft construction, why did its use fade away after WW2?

More info:

_"At Don Muang, they suffered a number of accidents on landing or in the circuit, and sadly encountered more serious __structural problems__ with their aircraft, one of which broke up in bad weather on a long flight to Singapore, causing the Squadron’s final losses of the Second World War."_

and...

_"*Structural problems*
The structural difficulties of the de Havilland Mosquito have been discussed in a number of places, most tellingly by Jefford in The Flying Camels (at Annex K).

It was eventually determined that the initial problems were the result of a combination of poor mate-up of some structural members, poor gluing practices and failure of glued joints, apparently most common among Far East aircraft after prolonged outdoor storage. It also appeared that swelling of the top skin could lead the securing screws to pull through.

Subsequent examination of European theatre aircraft found a much lower prevalence of joint defects, and no lifting of wing skins. Further investigation in India identified two main defects: the wing spar scarf joints, and the spar boom joints with the plywood skin and other ply members, leading to lifting of the upper surface plywood skin.

Consequently, Modification 638 was adopted: adding a spanwise plywood strip to seal the upper surface skin joint along the length of the front spar; along with application of protective aluminium dope overall (from February 1945). *Despite these efforts, in the tropical conditions of the Far East the combination of heat and water soakage continued to give rise to swelling and shrinkage, resulting in spar defects until as late as 1954."*_

de Havilland Mosquito


----------



## chuter (Jul 23, 2016)

pbehn said:


> I have never read anything about the meredith effect that discussed the mosquito, I found a long discussion about the Hornet and the main concern was disturbing the airflow under the wing. Would it be more accurate to say they had the best low drag solutions to cooling water cooled engines




Lee Atwood was describing the difficulty of designing the Mustang cooling duct and how they finally got that to work properly at a post-war engineer's convention where he also talked about how Supermarine and Messerschmitt failed and De Havilland got it right. According to him, having the coolers right on the leading edge made the rather tricky duct design much easier than when working with recessed coolers between the spars. I don't know if he had inside knowledge of a conscious attempt at achieving Meredith Effect at De Havilland or if he simply assumed they achieved it based on his own analysis of the Mossie's performance. The English always assumed the Mustang's speed was due entirely to its wing (until their experience with the Spiteful) because they failed with "Meredith" on the Spitfire but Lee acknowledged that the Mustang's laminar wing was unable to perform in the field as hoped while the cooling system performed beyond expectations.


----------



## pbehn (Jul 23, 2016)

chuter said:


> Lee Atwood was describing the difficulty of designing the Mustang cooling duct and how they finally got that to work properly at a post-war engineer's convention where he also talked about how Supermarine and Messerschmitt failed and De Havilland got it right. According to him, having the coolers right on the leading edge made the rather tricky duct design much easier than when working with recessed coolers between the spars. I don't know if he had inside knowledge of a conscious attempt at achieving Meredith Effect at De Havilland or if he simply assumed they achieved it based on his own analysis of the Mossie's performance. The English always assumed the Mustang's speed was due entirely to its wing (until their experience with the Spiteful) because they failed with "Meredith" on the Spitfire but Lee acknowledged that the Mustang's laminar wing was unable to perform in the field as hoped while the cooling system performed beyond expectations.


From what I have read the later Me109s had a quite good use of the meredith effect the spitfire was so/so depending on which model. As far as I know the thrust from the P51s meredith effect merely compensated for the drag of the inlet duct. On the Mosquito the outlet of the cooling system was under the wing, it couldnt provide forward thrust but then the inlet was in the wing leading edge and so didnt cate drag either. 

On the Hornet construction of a system to provide thrust by the Meredith effect was impossible due to the wing spar, the challenge was therefore to re introduce the airflow from the radiators without turbulence.


----------



## pbehn (Jul 23, 2016)

FLYBOYJ said:


> Read my first post - "Wood structures are hard to maintain and are susceptible to swelling and shrinkage depending on climate and environment," and I'll further elaborate, temperature - the cool humidity is actually good for wooden aircraft, don't move them to the desert.
> 
> You mention some combat exploits - agree, the Mosquito was a great aircraft.
> 
> ...



What you are saying is environments change and some materials are badly or well suited to them. Try using an RAF Harrier on a carrier and you will have similar problems to the Mosquito encountered. When you talk about the desert then you must understand deserts have many conditions. When I was in Saudi Arabia the humidity at night was frequently 99% your car was stood in a puddle every morning due to condensation, add in a sand storm when the sand is between 0.5 and 1% salt and you have a great environment for corrosion of aluminium. In two years in KSA I saw rain 3 times and despite that all cars there are rust buckets after 3 years.

I am not saying that the mosquito didnt have problems or that wood is a miracle material just that the Mosquiotos problems such as they were were minor compared to (for example) the Typhoons problems in winter getting it to start and in summer stopping the abrasive soil devouring the engine internals, similar situation in North Africa and Malta for Spitfires and Hurricanes


----------



## XBe02Drvr (Jul 23, 2016)

[QUOTE="pbehn, post: 1278340, member: As far as I know the thrust from the P51s meredith effect merely compensated for the drag of the inlet duct.[/QUOTE]
MERELY compensating for cooling drag is HUGE. For piston aircraft of just about any size, type, and performance class, cooling drag represents 30% to 40% of total airframe drag. Their's a lot more drag inside that little scoop than its frontal area would make you think. Cancel that with Meredith thrust, and you should more than compensate for a laminar wing that doesn't live up to its wind tunnel promise under field conditions.


----------



## FLYBOYJ (Jul 23, 2016)

pbehn said:


> What you are saying is environments change and some materials are badly or well suited to them. Try using an RAF Harrier on a carrier and you will have similar problems to the Mosquito encountered. When you talk about the desert then you must understand deserts have many conditions. When I was in Saudi Arabia the humidity at night was frequently 99% your car was stood in a puddle every morning due to condensation, add in a sand storm when the sand is between 0.5 and 1% salt and you have a great environment for corrosion of aluminium. In two years in KSA I saw rain 3 times and despite that all cars there are rust buckets after 3 years.
> 
> I am not saying that the mosquito didnt have problems or that wood is a miracle material just that the Mosquiotos problems such as they were were minor compared to (for example) the Typhoons problems in winter getting it to start and in summer stopping the abrasive soil devouring the engine internals, similar situation in North Africa and Malta for Spitfires and Hurricanes



Comparing Harrier ops to this is like comparing apples to a unicorn. Although aluminum can corrode, you can control it. When wood structures expand and contract, they weaken and split.

You're not getting it - changes in heat AND humidity or just one of will do in a wood aircraft. The humidity could be 99% in Saudi - if the aircraft was originally being operated in mild temps and it now sits in temps over 100F, the structure will shrink. Take it to a place that is zero humidity and still has high temps it will shrink even more. I worked on a Pitts brought to Southern California from Seattle. As soon as the temperatures rose, every metal fitting connected to wood structure loosened up, some of the wood screws were removable just by pulling on the heads. I've seen this on Mooneys and Bellancas as well. This will happen to ANY wood aircraft in time.

The fact that the IAF operated their Mosquitoes until 1957 is a miracle.


----------



## Thorlifter (Jul 24, 2016)

Question about the restored Mosquitos, especially the ones that are (or will be) flying.......

Are they being restored with wooden structures or are they using aluminum?


----------



## FLYBOYJ (Jul 24, 2016)

Thorlifter said:


> Question about the restored Mosquitos, especially the ones that are (or will be) flying.......
> 
> Are they being restored with wooden structures or are they using aluminum?


AFAIK they're using wood


----------



## Thorlifter (Jul 24, 2016)

I certainly would have thought they would use aluminum in the flying ones. To me, and I'm certainly not an aviation expert, restoring something with a material that has a shorter life span would be like putting the Jumo 004 engines back in the new ME-262's. And doing it just for historical accuracy certainly isn't the answer (at least to me). Now if you are restoring a static Mossy, that would be fine.


----------



## XBe02Drvr (Jul 24, 2016)

Thorlifter said:


> I certainly would have thought they would use aluminum in the flying ones. To me, and I'm certainly not an aviation expert, restoring something with a material that has a shorter life span would be like putting the Jumo 004 engines back in the new ME-262's. And doing it just for historical accuracy certainly isn't the answer (at least to me). Now if you are restoring a static Mossy, that would be fine.



Repair techniques on aircraft structures are required to use materials and methods identical or extremely similar to the original. How would you interface wood structure and metal repair in a way that's approved and proven to be as strong as the original? Metal structures are held together by point contact fasteners such as rivets or screws, which are acceptable because the sheet metal is strong enough to withstand the concentration of stress around the fasteners without their tearing through. Plywood construction a la Mosquito is fastened by adhesives which spread the stress along the entire joint rather than concentrating it at each fastener. Point contact fasteners are the weak points in wood structures.

Reactions: Agree Agree:
1 | Like List reactions


----------



## GrauGeist (Jul 24, 2016)

XBe02Drvr said:


> Repair techniques on aircraft structures are required to use materials and methods identical or extremely similar to the original. How would you interface wood structure and metal repair in a way that's approved and proven to be as strong as the original? Metal structures are held together by point contact fasteners such as rivets or screws, which are acceptable because the sheet metal is strong enough to withstand the concentration of stress around the fasteners without their tearing through. Plywood construction a la Mosquito is fastened by adhesives which spread the stress along the entire joint rather than concentrating it at each fastener. Point contact fasteners are the weak points in wood structures.


As long as the laminate can tolerate the stress.

This was the problem the Germans ran into with their Tego film for their laminates and cost them a great deal, in the way of delays and setbacks: especially with the Ta154, which was a victim of the delaminating wood composites.


----------



## Graeme (Jul 24, 2016)

Flak damage. Amazingly it got home, but would the damage be less if the wing was metal?


----------



## XBe02Drvr (Jul 24, 2016)

I doubt it.


----------



## pbehn (Jul 24, 2016)

FLYBOYJ said:


> Comparing Harrier ops to this is like comparing apples to a unicorn. Although aluminum can corrode, you can control it. When wood structures expand and contract, they weaken and split.
> 
> You're not getting it - changes in heat AND humidity or just one of will do in a wood aircraft. The humidity could be 99% in Saudi - if the aircraft was originally being operated in mild temps and it now sits in temps over 100F, the structure will shrink. Take it to a place that is zero humidity and still has high temps it will shrink even more. I worked on a Pitts brought to Southern California from Seattle. As soon as the temperatures rose, every metal fitting connected to wood structure loosened up, some of the wood screws were removable just by pulling on the heads. I've seen this on Mooneys and Bellancas as well. This will happen to ANY wood aircraft in time.
> 
> The fact that the IAF operated their Mosquitoes until 1957 is a miracle.


I do "get it" what I dont get is that people always quote conditions in the far east, heat and humidity. The temperature change from a summers day at ground level in England to that at 40,000 ft is about 60C. In the radiator area the temperature on a winters day could change from minus 20C to plus 100C in minutes. The airframe of any mosquito anywhere in temperate England survived massive temperature and humidity variation yet everyone discusses the humidity in the far east.

You control the corrosion on Harrier ops by building a Sea Harrier.


----------



## pbehn (Jul 24, 2016)

XBe02Drvr said:


> [QUOTE="pbehn, post: 1278340, member: As far as I know the thrust from the P51s meredith effect merely compensated for the drag of the inlet duct.


MERELY compensating for cooling drag is HUGE. For piston aircraft of just about any size, type, and performance class, cooling drag represents 30% to 40% of total airframe drag. Their's a lot more drag inside that little scoop than its frontal area would make you think. Cancel that with Meredith thrust, and you should more than compensate for a laminar wing that doesn't live up to its wind tunnel promise under field conditions.[/QUOTE]
Maybe a bad choice of words, not saying it wasnt important just that the P51 didnt have a secret rocket pushing it along.


----------



## FLYBOYJ (Jul 24, 2016)

pbehn said:


> I do "get it" what I dont get is that people always quote conditions in the far east, heat and humidity. The temperature change from a summers day at ground level in England to that at 40,000 ft is about 60C. In the radiator area the temperature on a winters day could change from minus 20C to plus 100C in minutes. The airframe of any mosquito anywhere in temperate England survived massive temperature and humidity variation yet everyone discusses the humidity in the far east.



Those temperature variations you talk about are seasonal - what is the aircraft being exposed to when it rests at the end of the day? What is the AVERAGE ambient temperatures and humidity it will see?

The link I posted proves my point and I know the RAAF wasn't the only post war operator who had maintenance issues with the Mosquitoes that eventually led to its retirement. Again, I've worked with wood aircraft and seen these issues - if you have information experience that proves me wrong, I'm all ears!

_"Its wood construction provided it’s greatest strength during the war, but was also its Achilles’ heel. While metal aircraft endured after the war, Mosquitos rotted away, between the wood decomposing and the loss of adhesion of the animal-based glues that held the plywood together, few Mosquitos survived long and very few remained airworthy to display on the air show circuits of the world, which caused the plane to fall to an undeserved level of obscurity."

Airworthy de Havilland Mosquito Restoration Approaches Completion in Canada_




pbehn said:


> You control the corrosion on Harrier ops by building a Sea Harrier.


Ok - now we're talking metal planes...

I could tell you that structurally both aircraft are about the same, some dissimilar metal parts were changed to avoid bimetallic corrosion, the Sea Harrier uses different corrosion coatings and inhibitors, but these are EXTERNAL treatments and little to do with this discussion.


----------



## pbehn (Jul 24, 2016)

FLYBOYJ said:


> Those temperature variations you talk about are seasonal - what is the aircraft being exposed to when it rests at the end of the day? What is the AVERAGE ambient temperatures and humidity it will see?
> 
> The link I posted proves my point and I know the RAAF wasn't the only post war operator who had maintenance issues with the Mosquitoes that eventually led to its retirement. Again, I've worked with wood aircraft and seen these issues - if you have information experience that proves me wrong, I'm all ears!


Good info FBJ, my point is, the fact that the Mosquito is an aeroplane going from ground level to 40,000 ft in summer and winter is what makes the structure vulnerable. Talk of mildew in the far east being a problem makes me laugh, as if a plane parked outside in the UK wouldnt get mildew. If water is allowed to get into the wood it will fall apart very quickly I would think, because it will freeze at altitude. Its the thing about humidity in the far east being a particular and chronic problem that I disagree with.


FBJ post number 37 was not made by me


----------



## FLYBOYJ (Jul 24, 2016)

pbehn said:


> Good info FBJ, my point is, the fact that the Mosquito is an aeroplane going from ground level to 40,000 ft in summer and winter is what makes the structure vulnerable. *Talk of mildew in the far east being a problem makes me laugh, as if a plane parked outside in the UK wouldnt get mildew. If water is allowed to get into the wood it will fall apart very quickly I would think, because it will freeze at altitude.* Its the thing about humidity in the far east being a particular and chronic problem that I disagree with.



Mildew will build up if you have no air movement around the wood structure. Around 71F with 30% humidity is the perfect environment for dry rot. 



pbehn said:


> FBJ post number 37 was not made by me



I'm trying to figure that one out.


----------



## wuzak (Jul 24, 2016)

FLYBOYJ said:


> _"Its wood construction provided it’s greatest strength during the war, but was also its Achilles’ heel. While metal aircraft endured after the war, Mosquitos rotted away, between the wood decomposing and the loss of adhesion of the animal-based glues that held the plywood together, few Mosquitos survived long and very few remained airworthy to display on the air show circuits of the world, which caused the plane to fall to an undeserved level of obscurity."
> 
> Airworthy de Havilland Mosquito Restoration Approaches Completion in Canada_.



One of the main reasons that so few survived long after the war is that most of them were scrapped.


----------



## gumbyk (Jul 25, 2016)

Thorlifter said:


> I certainly would have thought they would use aluminum in the flying ones. To me, and I'm certainly not an aviation expert, restoring something with a material that has a shorter life span would be like putting the Jumo 004 engines back in the new ME-262's. And doing it just for historical accuracy certainly isn't the answer (at least to me). Now if you are restoring a static Mossy, that would be fine.


These ones are wooden: Mosquito Aircraft Restoration. Sourcing materials around the world

The way these aircraft will be treated and flown isn't really comparable to the way they were in service. These will all be hangared, and generally kept in controlled conditions.
As stated earlier, the change of conditions is the problem with wooden aircraft, so these will likely have a much longer service life.

Using aluminium means you are building a replica, not a restoration.

Personally, I don't think twice about flying in a wooden aircraft, because I know the engineers know how to maintain it properly.

Also, I've heard rumblings of another test flight approaching...

Reactions: Like Like:
1 | Like List reactions


----------



## drgondog (Jul 26, 2016)

XBe02Drvr said:


> [QUOTE="pbehn, post: 1278340, member: As far as I know the thrust from the P51s meredith effect merely compensated for the drag of the inlet duct.


MERELY compensating for cooling drag is HUGE. For piston aircraft of just about any size, type, and performance class, cooling drag represents 30% to 40% of total airframe drag. Their's a lot more drag inside that little scoop than its frontal area would make you think. Cancel that with Meredith thrust, and you should more than compensate for a laminar wing that doesn't live up to its wind tunnel promise under field conditions.[/QUOTE]

For the P-51D/H (H slightly lower) the cooling drag is important for low speed flight, including climb, gradually shrinking to Net drag near zero as RN approaches 15x10^^6 due to the thrust generated by Meredith Effect.

At RN=2x10^^6 the external drag (at CL=0) for the Radiator Duct (per NAA Report NA-8449) is .0019. In comparison the Empennage Drag = .0022. In climb the Delta Cooling Drag at approx. 9.88x10^^6 at SL is .0064 which as you note is substantial

Reactions: Like Like:
2 | Like List reactions


----------



## pbehn (Jul 26, 2016)

drgondog said:


> MERELY compensating for cooling drag is HUGE. For piston aircraft of just about any size, type, and performance class, cooling drag represents 30% to 40% of total airframe drag. Their's a lot more drag inside that little scoop than its frontal area would make you think. Cancel that with Meredith thrust, and you should more than compensate for a laminar wing that doesn't live up to its wind tunnel promise under field conditions.



For the P-51D/H (H slightly lower) the cooling drag is important for low speed flight, including climb, gradually shrinking to Net drag near zero as RN approaches 15x10^^6 due to the thrust generated by Meredith Effect.

At RN=2x10^^6 the external drag (at CL=0) for the Radiator Duct (per NAA Report NA-8449) is .0019. In comparison the Empennage Drag = .0022. In climb the Delta Cooling Drag at approx. 9.88x10^^6 at SL is .0064 which as you note is substantial[/QUOTE]
Great info dd, I was merely stating that the thrust compensates for the drag so is not actually a net thrust, the Mosquito which had inlets in the wing leading edge presumably was lower than using a scoop inlet.


----------



## Zipper730 (Jul 26, 2016)

Blitzrockie said:


> P 51 vs Mosquito?
> If these planes were engage each other who would win?


Which variants? You do realize that there were several P-51 variants, and more Mosquito variants than letters in the English alphabet?



drgondog said:


> MERELY compensating for cooling drag is HUGE. For piston aircraft of just about any size, type, and performance class, cooling drag represents 30% to 40% of total airframe drag.


WOW that's substantial



> For the P-51D/H (H slightly lower) the cooling drag is important for low speed flight, including climb, gradually shrinking to Net drag near zero as RN approaches 15x10^^6 due to the thrust generated by Meredith Effect.


RN is Reynolds Numbers?



pbehn said:


> For the P-51D/H (H slightly lower) the cooling drag is important for low speed flight, including climb, gradually shrinking to Net drag near zero as RN approaches 15x10^^6 due to the thrust generated by Meredith Effect.
> 
> At RN=2x10^^6 the external drag (at CL=0) for the Radiator Duct (per NAA Report NA-8449) is .0019. In comparison the Empennage Drag = .0022.


If we're talking reynolds numbers, isn't that a function of scale?



> In climb the Delta Cooling Drag at approx. 9.88x10^^6 at SL is .0064 which as you note is substantial


Why would there be differences in cooling drag in the climb? Is that due to speed, AoA, propeller pitch, or something else?


----------



## drgondog (Jul 26, 2016)

Zipper - too many questions.
Start with RN = MAC*V*rho/Mu where Mu = absolute viscosity, Rho= density, MAC = Mean Aero Chord, V=velocity for Incompressible flow.

For a Mustang, Cooling drag is important in all low speed/medium speed flight regimes.

Cooling Drag Delta in Climb is definitely in low/medium low velocity regime for RN. Primarily a function of airspeed and density.


----------



## wuzak (Jul 26, 2016)

drgondog said:


> Cooling Drag Delta in Climb is definitely in low/medium low velocity regime for RN. Primarily a function of airspeed and density.



Also the cooling outlet flap must contribute to some drag also?


----------



## parsifal (Jul 26, 2016)

I respect the great experience many of you guys have with regard to maintenance and longevity issues. I am no expert. never worked on aircraft maintenance never had to tackle the problems of aircraft repair. I freely admit that

however I do know the theory of hypothesis, theory, proven theory and fact, and with respect guys, your neat comfortable claims about how crappy wooden airframes are and how easily they fall apart , in order to be considered or shown to be "a fact" would need to be shown in every case, and in every subset applicable. with respect, that hasn't happened. It would have substantial weight if it was shown to be the case in most situations or in most scenarios. maybe . I don't have information either way to prove that one way or the other. but if there is a subset of a group where their is a consistent disproving of a theory, or exception to your thgeory, then the theory is busted, and you have to go out and rethink your position. If you can find a situation where 2+2 does not always equal 4, then the "fact" that 2+2 = 4 is completely busted 9and incidentally ther are statistical anomalies where 2+2 does equal 4 but lets not go there for now).

Here is a link to the RAAF mosquitoes, many of which remained in service until 1954, some even as late as 1958. I doubt that may p-51s, built 1944-5 could rmain in service as late as 1958....the actual airframes built in 1944-5 I mean. because their is such a massive exception to the rule you guys are attempting to establish, I consider the whole preposition on which the theory is based is busted.

ADF Serials - Mosquito


----------



## GrauGeist (Jul 26, 2016)

parsifal said:


> ...I doubt that may p-51s, built 1944-5 could rmain in service as late as 1958....the actual airframes built in 1944-5 I mean...


Air National Guard units were given surplus P-47 and P-51 types from 1946 onward.

Some Guard units retained their P-51D/K/H well into the 1950's and the West Virginia Air National Guard was the last Guard unit to retire their P-51s, doing so on 25 January 1957.

The WVANG 167th FS was operating F-51D-25-NA and F-51D-30-NA types, with such S/Ns as 44-73574, 44-74936, 44-79248, etc.


----------



## FLYBOYJ (Jul 26, 2016)

wuzak said:


> One of the main reasons that so few survived long after the war is that most of them were scrapped.



Because they were falling apart?


----------



## wuzak (Jul 26, 2016)

FLYBOYJ said:


> Because they were falling apart?





Surplus to requirements.

Reactions: Like Like:
1 | Like List reactions


----------



## XBe02Drvr (Jul 26, 2016)

parsifal said:


> I respect the great experience many of you guys have with regard to maintenance and longevity issues. I am no expert. never worked on aircraft maintenance never had to tackle the problems of aircraft repair. I freely admit that
> 
> Here is a link to the RAAF mosquitoes, many of which remained in service until 1954, some even as late as 1958. I doubt that may p-51s, built 1944-5 could rmain in service as late as 1958....the actual airframes built in 1944-5 I mean. because their is such a massive exception to the rule you guys are attempting to establish, I consider the whole preposition on which the theory is based is busted.
> 
> ADF Serials - Mosquito



Hey let's quit with this "theory of hypothesis" crap! It's a practical world out there, and practical experience has shown that wood is a way more active and less stable material than aluminum in the commonly experienced regimes of temperature and humidity that aircraft are routinely subjected to. It's also a known and accepted fact that the adhesives available in Mosquito days weren't anywhere near as durable and long-lasting as what we have today.
Reading your Australian S/N list seems to indicate that the vast majority of these birds, while still on the active list, were in storage from 1945-46 to 1953-54, and then were pulled out and sold or "returned to components", in other words, SCRAPPED. There also seem to be an inordinate number of in-flight structural failures, way more than you would see with all-metal aircraft like the Mustang. While not proof in the theoretical sense, this looks to me like like really strong evidence for the reduced durability of the Mosquito's wooden structure.
As for the Mustang's durability, they were retired in good mechanical and structural condition due to obsolescence.


----------



## XBe02Drvr (Jul 26, 2016)

Zipper730 said:


> Why would there be differences in cooling drag in the climb? Is that due to speed, AoA, propeller pitch, or something else?



I think you'll find it has to do with ram effect. Less relative wind and more AOA means the air has to bend around to enter the scoop and hits the radiator with less impulse. Like an early centrifugal flow jet, less ram in the front means less thrust out the back.


----------



## parsifal (Jul 26, 2016)

so if we are going to ditch the proven method for testing theory and rely on (claimed) experience, we are basically going to rely who can shout the loudest and longest. a variation of the used car salesman or snake oil merchants in other words. sorry, I'll stick to the proven methods of testing a theory as has been applied in every other sphere of theoretical research. advance a theory, If exceptions on a significant scale are found the theory aint cutting the mustard. not my problem to find the alternative, simply to disprove the comfortable positions being touted as gospel by those with experience.

now, you've suggested the Mosquito fates shown in the ADF serials for mossies suggests an inherent structural problem. many held in storage, many just scrapped . your right that many were scrapped, but we don't know why really, well I do know some, but not all of them and the ones I do know weren't scrapped because they were falling apart. most went to the wreckers yard because of obsolescence. but to do the job properly we would have to look at the particulars for each airframe to really get to the heart of that, but it is at least relevant to also look at the fates of CAC built P-51s in the post war period. many of the airframes that were extant in 1945 were scrapped by 1947, all were gone by 1953 I think. p-51s were last used operationally in the RAAF in 1950 before being replaced by meteor F8s. The theory you are espousing, on the basis of your "experience' is falling apart on the basis of what actually happened 'in the real world" your insistence on relying on the "practical" is falling apart at the starting gate I would suggest.

Here are the fates of the RAAF P-51s. go ahead and have a look at when and what happened to them.

ADF Serials - Mustang

like I said, the theory is busted.....time to suggest a new one


----------



## parsifal (Jul 27, 2016)

Other aircraft in RAAF service worth looking at with respect to longevity of service

Meteor f8.....metal airframe, jet engine, entered service 1952, retired from frontline 1958, about half remained in air reserve until 1963....11 years of service

CAC Ca 27 avon Sabre....metal airframe , entered service 1954, retired from frontline 1964, a few were passed to Malaysia and Indonesia after overhaul, in service until 1970s, but basically with low hours. RAAF service 10 years

Mirage III, 105 built, but never more than 40 in service at any one time. In service from 1964 to 1984, maybe 15 years for each airframe.


I don't see a pattern that cries out metal frame= longer service life. what I see is metal frame irrelevant to service life. engine tech, yes, type obsolescence yes airframe type, mor dependant on its usefulness more than anything. wood, metal, aint got squat to do with it.


----------



## FLYBOYJ (Jul 27, 2016)

parsifal said:


> I doubt that may p-51s, built 1944-5 could rmain in service as late as 1958









*"The Dominican Republic received surplused P-51D's from Sweden 1952/1953 as an addition to a few aircraft purchased from the U.S. during the late 1940's, and kept them in continuous service for over 30 years until finally retired in 1984! During that long service-life, the aircraft saw several IRAN's (Inspection and Repair as Necessary) and upgrading, mostly done by TFA / Cavalier at Sarasota, FL. A few aircraft were added from other sources to replace losses, and some aircraft were cannibalized for spare parts."*

These Mustangs came from Sweden. Here's their history...

N.A. Mustang in Swedish service


----------



## FLYBOYJ (Jul 27, 2016)

* P-51D-20-NA "Upupa Epops" Serial Number 44-72364* 

_Built by North American during 1944. Assigned to the US Army Air Force (USAAF). 

*Wartime History*
Assigned to the US Army Air Force (USAAF) to the 8th Air Force, 353rd Fighter Group, 352nd Fighter Squadron. On March 1, 1945 assigned to pilot Captain Harrison B. "Bud" Tordoff who nicknamed the plane "Upupa Epops", the scientific name for the Hoopoe Bird.

For the next six weeks, this aircraft was flown by Tordoff on combat missions over Europe. On March 31, 1945 Tordoff calimed an enemy aircraft. On April 7, 1945 Tordoff claimed a Me-262 shot down at long range, his fifth claimed victory.

*Postwar*
* During 1947, this aircraft was sold to Sweden. Assigned to the Flygvapnet (Swedish Air Force) coded "Fv26061". Operated in Sweden until 1954. Afterwards, sold to the Dominican Republic arriving on October 31, 1952. Assigned to the Fuerza Aérea Dominicana (Dominican Air Force) coded "FAD 1916". *

*During 1984, purchased by Florida warbird dealer Brian O'Farrell and transported to the United States. In 1999, acquired by "a shadowy consortium of airline pilots in the Pacific Northwest", presumed to be *__*Vulcan Warbirds*__* / *__*Paul Allen Collection*__*.*

*Restoration*
During the early 2000s, restored over two and half years by __WestPac Restoration (Klaers Aviation)__ at __Rialto Airport__. Restored to flying condition and painted in the wartime markings of "Upupa Epops". 

*Display*
On May 12, 2004 registered with the FAA as N723FH by __Vulcan Warbirds__ and flown to Arlington, Washington to the __Flying Heritage Collection (FHC) / Paul Allen Collection__ at Arlington, Washington. 

Since 2004, displayed at the __Flying Heritage Collection (FHC) / Paul Allen Collection__. At the opening of the museum, this aircraft was reunited with former pilot Tordoff. Displayed with original maps used by former pilot Tordoff._

Pacific Wrecks


----------



## FLYBOYJ (Jul 27, 2016)

P-51 Mustang Survivors - MustangsMustangs.com


----------



## gumbyk (Jul 27, 2016)

XBe02Drvr said:


> Hey let's quit with this "theory of hypothesis" crap! It's a practical world out there, and practical experience has shown that wood is a way more active and less stable material than aluminum in the commonly experienced regimes of temperature and humidity that aircraft are routinely subjected to. It's also a known and accepted fact that the adhesives available in Mosquito days weren't anywhere near as durable and long-lasting as what we have today.



Wood does have its advantages, mainly that it doesn't fatigue anywhere near as much as aluminium does However, storage and maintenance is much more critical.

Our tiger has only just had its 70+ year old tailplane replaced due to damage, and there is still a lot of original structural wood in there, so it would have been _possible_ to maintain a Mossie. But the cost and effort required to do this would be disproportionate. And that's just the cost of maintaining the fuselage - you've still got to maintain and feed two hungry V-12's.

Reactions: Like Like:
2 | Like List reactions


----------



## parsifal (Jul 27, 2016)

I think the situation is variable. During WWII the average lifespan of a given airframe might be 6-12 months of frontline service. I don't think being made of wood or metal is going to make all that much difference in that time frame. 

In peace time we have examples of wood framed a/c being used operationally for 10+ years, and metal framed a/c being used for 5-50 years, average say 10 years, getting longer for the newer types. I just cant see that airframe is the main determinant of long term longevity. I think the usefulness of the airframe has more to do with it. in peace time the airframe will get looked after, so it doesn't wear out so much as just stops being useful.


----------



## pbehn (Jul 27, 2016)

There are still airworthy examples of the Dh Dragon Rapide.


----------



## FLYBOYJ (Jul 27, 2016)

parsifal said:


> Other aircraft in RAAF service worth looking at with respect to longevity of service
> 
> Meteor f8.....metal airframe, jet engine, entered service 1952, retired from frontline 1958, about half remained in air reserve until 1963....11 years of service
> 
> ...



In the examples you cite you're looking at metal aircraft that became obsolete very quickly and were basically surpassed by technology. The Mirage III came along during a time where the advances made in aircraft fighter design and construction ensured its longevity.



parsifal said:


> I think the situation is variable. During WWII the average lifespan of a given airframe might be 6-12 months of frontline service. I don't think being made of wood or metal is going to make all that much difference in that time frame.
> 
> In peace time we have examples of wood framed a/c being used operationally for 10+ years, and metal framed a/c being used for 5-50 years, average say 10 years, getting longer for the newer types. I just cant see that airframe is the main determinant of long term longevity. I think the usefulness of the airframe has more to do with it. in peace time the airframe will get looked after, so it doesn't wear out so much as just stops being useful.



Give examples of wood aircraft operated in a high use military role after WW2! And I'm not talking mapping or target tugs! The RAAF Mossies had issues as was previously shown. As shown, Mustangs that saw combat in WW2 were still being operated in a combat role into the 1980s.
Some delivered in 1945 saw combat as late as 1969.

C-47's as bombers, P-51 Mustangs vs Corsairs, the very last All Piston Prop Aerial War! - The Dakota Hunter

Bottom line, wood aircraft in military applications during the post war years was not an option for continual. The IDF was the only operator to use the Mosquito in a *combat role* into 1957 and even then they had issues. Iit was a miracle the IDF operated the Mosquito for as long as it did!


pbehn said:


> There are still airworthy examples of the Dh Dragon Rapide.



As with many antique wood airframes with low yearly operating hours, but look at how they are maintained, flown and stored - basically pampered as they should be.

Gumbyk hit the nail on the head in his post last page;

"Wood does have its advantages, mainly that it doesn't fatigue anywhere near as much as aluminium does However, *storage and maintenance is much more critical.*

Our tiger has only just had its 70+ year old tailplane replaced due to damage, and there is still a lot of original structural wood in there, so it would have been _possible_ to maintain a Mossie.* But the cost and effort required to do this would be disproportionate. And that's just the cost of maintaining the fuselage* - you've still got to maintain and feed two hungry V-12's."


----------



## drgondog (Jul 27, 2016)

XBe02Drvr said:


> I think you'll find it has to do with ram effect. Less relative wind and more AOA means the air has to bend around to enter the scoop and hits the radiator with less impulse. Like an early centrifugal flow jet, less ram in the front means less thrust out the back.



This is part of the explanation but the real root is that the Parasite drag increase is almost linear with change to CL/angle of attack - from a low of Zero lift to a significantly higher value based on increase to CL.

This is a MAJOR factor to loss of energy in high AoA maneuver - namely the increase to Parasite Drag over cruise or level flight envelope.

Reactions: Informative Informative:
1 | Like List reactions


----------



## gumbyk (Jul 27, 2016)

parsifal said:


> I think the situation is variable. During WWII the average lifespan of a given airframe might be 6-12 months of frontline service. I don't think being made of wood or metal is going to make all that much difference in that time frame.
> 
> In peace time we have examples of wood framed a/c being used operationally for 10+ years, and metal framed a/c being used for 5-50 years, average say 10 years, getting longer for the newer types. I just cant see that airframe is the main determinant of long term longevity. I think the usefulness of the airframe has more to do with it. in peace time the airframe will get looked after, so it doesn't wear out so much as just stops being useful.


The thing with wooden structure is that it very easy to get into a situation where it is beyond economical repair; either because of the labour and skills required or due to the amount of material needing to be replaced.

So while a wooden aircraft _could_ have been continued in service - it wasn't economical to do so, IMO.

Reactions: Like Like:
4 | Like List reactions


----------



## parsifal (Jul 27, 2016)

Wood continued to be used for at least 10 years after the war in military aircraft in the eastern block, because the formula they were using for airpower was totally different to the formula employed in the US where such shortages and economies were never an issue. . The use of wood is, (especially un-laminated) inherently weaker and more prone to critical damage than metal, but it has its advantages that are especially useful in wartime. It uses non-strategic materials, it uses skill and a workforce generally underutilised in wartime and frees up more specialised metal working and alloy production for more critical jobs. in the case of the Soviets they opted for those wood construction. Using wooden airframes with fabric coverings allowed them to divert their meagre alloy production and metal working capable workforce to the production of AFVs which they played to their maximum advantage. they didn't produce more than 80000 T-34s with only the 5th largest economy using our formulas for production. They also used steel framing in their IL-2s and 10s, a non-strategic material, another variation to avoiding use of critical materials and skills 

in the post war situation where wartime pressure don't exist, it doesn't make sense to build in wood. it is an inherently weaker material, but this is not a major factor in determining airframe longevity. mentioning the so-called issues about RAAF mossies post war, it was just one of perhaps half a dozen types that we had in surplus in 1945, and yet it was the mosquito that was selected to map half of SE Asia and then provide recon as late as 1954. RAAF mosquitoes incidentally that were selected for retention were all photo recon variants, so they retained their primary roles until retiremement at the beginning of malaya. 

ive deliberately kept my comments confined to RAAF, to maintain some semblance of comparability. Talking about some Sth American airforce and how it retains a wwii crate in service for 50 years may not be comparable to another user. they may have lower airworthiness criteria, lesser annual hours per airframe, just plain acceptance they don't need top shelf toys for their forces. I don't know that the claim that these air forces, if equipped with a mosquito or two instead of a p-51 or two, might not still try and fly them 30 years after their use by date, once or twice a year, or how ever many times, or accept attrition rates totally unacceptable to a modern western air force. the two subsets are just not that comparable


----------



## FLYBOYJ (Jul 27, 2016)

parsifal said:


> Wood continued to be used for at least 10 years after the war in military aircraft in the eastern block, because the formula they were using for airpower was totally different to the formula employed in the US where such shortages and economies were never an issue. . The use of wood is, (especially un-laminated) inherently weaker and more prone to critical damage than metal, but it has its advantages that are especially useful in wartime. It uses non-strategic materials, it uses skill and a workforce generally underutilised in wartime and frees up more specialised metal working and alloy production for more critical jobs. in the case of the Soviets they opted for those wood construction. Using wooden airframes with fabric coverings allowed them to divert their meagre alloy production and metal working capable workforce to the production of AFVs which they played to their maximum advantage. they didn't produce more than 80000 T-34s with only the 5th largest economy using our formulas for production. They also used steel framing in their IL-2s and 10s, a non-strategic material, another variation to avoiding use of critical materials and skills



Parsifal - please provide some sources for your claims! The only East bloc post war military aircraft that I could think of off the top of my head that used some wood in it's primary structure was the AN-2 and maybe some of the early Yak jets.

AFAIK the IL-10 used no wood in any primary structure


parsifal said:


> in the post war situation where wartime pressure don't exist, it doesn't make sense to build in wood. it is an inherently weaker material, *but this is not a major factor in determining airframe longevity.* mentioning the so-called issues about RAAF mossies post war, it was just one of perhaps half a dozen types that we had in surplus in 1945, and yet it was the mosquito that was selected to map half of SE Asia and then provide recon as late as 1954. RAAF mosquitoes incidentally that were selected for retention were all photo recon variants, so they retained their primary roles until retiremement at the beginning of malaya.



Sorry, but you're wrong - wood has an eventual "shelf life" dictated my mother nature and eventually you could only do so much to maintain it unless you have very deep pockets. Either maintenance costs or mother nature will eventually catch up with it, especially if it's flown in environments that could easily produce dry rot and if you're flying the aircraft "hard." Again, if you have some documented "proof" to show that this is just not an opinion, I'd like to hear it.


parsifal said:


> ive deliberately kept my comments confined to RAAF, to maintain some semblance of comparability. Talking about some Sth American airforce and how it retains a wwii crate in service for 50 years may not be comparable to another user. they may have lower airworthiness criteria, lesser annual hours per airframe, just plain acceptance they don't need top shelf toys for their forces. I don't know that the claim that these air forces, if equipped with a mosquito or two instead of a p-51 or two, might not still try and fly them 30 years after their use by date, once or twice a year, or how ever many times, or accept attrition rates totally unacceptable to a modern western air force. the two subsets are just not that comparable



Now you're really showing that you don't know what you're talking about. As stated, the Dominican AF operated the P-51 (about 30 of them) regularly for over 30 years, and as shown, some of the same airframes flew in WW2 - If you could provide proof that they lowered their maintenance standards, please do tell, I'm all ears!!!!

Do you have operational statistics or attrition rates of these airforces to back up your claims????

As far as frequency of operation - look into the history of Central and South American airforces and then let's have a realistic conversation. BTW, the Dominican AF operated the Mosquito as well, 5 FB.6s they lasted 6 years before they were retired.


----------



## FLYBOYJ (Jul 27, 2016)

Just for the record, the Spartan Aviation of Otowa operated late model B.35s starting in 1955 that were refurbished for high altitude mapping. These were commercially flown and lasted into the mid1960s, and from what I understand these aircraft were not stressed, hangared and meticulously maintained, but eventually mother nature caught up with them too.


----------



## gumbyk (Jul 27, 2016)

Don't forget that De Havilland continued to use wood post-war, including in the Venom and Vampire jets, so the fact of utilising other skills for manufacturing doesn't hold water, IMO. Post-war aluminium workers would have been a dime a dozen.

Comparing Al with unlaminated wood is a bit of a straw-man argument, as unlaminated wood was very rarely (if ever) used in an airframe.

If there was a will to have maintained these aircraft, they would have been. The IAF managed to retain their Vampire trainers in service from 1953 to 1982...

Reactions: Like Like:
1 | Like List reactions


----------



## FLYBOYJ (Jul 27, 2016)

gumbyk said:


> Don't forget that De Havilland continued to use wood post-war, including in the Venom and Vampire jets, so the fact of utilising other skills for manufacturing doesn't hold water, IMO. Post-war aluminium workers would have been a dime a dozen.
> 
> Comparing Al with unlaminated wood is a bit of a straw-man argument, as unlaminated wood was very rarely (if ever) used in an airframe.
> 
> If there was a will to have maintained these aircraft, they would have been. The IAF managed to retain their Vampire trainers in service from 1953 to 1982...



The most stressed parts of both aircraft were metal. The cockpits and gun bay doors were wood (varied from model-to-model) and from what I understand some operators replaced some of the wooden doors and panels with metal.


----------



## gumbyk (Jul 27, 2016)

The main change between the DH99 and DH100 was that the fuselage was wooden in the DH100, so there is more than just covers and doors.


----------



## FLYBOYJ (Jul 27, 2016)

I think the cockpit area and exterior was where most of the wood was located. In that case I could see better management of the wood structure as opposed to the wings. The Vampire that was raced at Reno last year was defiantly wood and if I remember it was the whole cockpit area


----------



## nuuumannn (Jul 27, 2016)

The whole forward fuselage of Vampires and Venoms/Sea Venoms is wood, forward for the firewall. The same construction method as the Mossie. The wings and tail booms are metal.



> There are still airworthy examples of the Dh Dragon Rapide.



I don't think it's fair to include restored airworthy aircraft as examples here, because not a scrap of original wooden structure in these flying oldies is as built - it'd all be new build components, post restoration. This includes the Mossie 'restorations' here in New Zealand. These aircraft are, despite the 'restoration' tag, new build machines; all the wooden structure is built from scratch, and therefore these wooden structured machines are kept in as pristine condition as possible, I.e. constantly hangared, good inspection and maintenance, as well as not subjected to the kinds of flight loads that a combat aircraft is subject to etc.

Reactions: Agree Agree:
1 | Like List reactions


----------



## chuter (Jul 30, 2016)

pbehn said:


> From what I have read the later Me109s had a quite good use of the meredith effect the spitfire was so/so depending on which model. As far as I know the thrust from the P51s meredith effect merely compensated for the drag of the inlet duct. On the Mosquito the outlet of the cooling system was under the wing, it couldnt provide forward thrust but then the inlet was in the wing leading edge and so didnt cate drag either.
> 
> On the Hornet construction of a system to provide thrust by the Meredith effect was impossible due to the wing spar, the challenge was therefore to re introduce the airflow from the radiators without turbulence.





The 109 briefly flirted with Meredith only with the F series. Key to the effect is laminar flow, and to achieve this a boundary layer bypass duct was installed but the very abrupt divergence of the forward volume of the duct caused the flow to stall at high speed - just where you're counting on it not to (exact same issue on the Spitfire). Because of this the G series and subsequent had this bypass duct removed to make room for a slightly larger cooler as it was deemed the bypass volume was essentially wasted space if it couldn't do it's job.. (The Mustang moved the scoop intake away from the airframe to avoid boundary layer turbulence in the first place.)

As for the Mosquito's underwing cooling exhaust not being able to provide thrust ... of course it could. There are lots of examples of thrust recovery outlets on aircraft that are parallel to the local airframe. I'm not sure where your assertion comes from. And even if a cooling duct doesn't increase frontal area in can still create a bunch of drag. (One could say a radial engine doesn't increase frontal area - lol).


----------



## pbehn (Jul 30, 2016)

chuter said:


> As for the Mosquito's underwing cooling exhaust not being able to provide thrust ... of course it could. There are lots of examples of thrust recovery outlets on aircraft that are parallel to the local airframe. I'm not sure where your assertion comes from. And even if a cooling duct doesn't increase frontal area in can still create a bunch of drag. (One could say a radial engine doesn't increase frontal area - lol).


I was reading the link below, from what I can glean the considerations of thrust/meredith effect were tied in with achieving low turbulence in the airflow. To my simplistic mind the more effective any meredith effect is the more likely you are to create drag at the inlet. The target was to achieve as close to zero cooling drag,





Some questions after reading the DH Hornet book...


----------



## chuter (Jul 31, 2016)

pbehn said:


> I was reading the link below, from what I can glean the considerations of thrust/meredith effect were tied in with achieving low turbulence in the airflow. To my simplistic mind the more effective any meredith effect is the more likely you are to create drag at the inlet. The target was to achieve as close to zero cooling drag,
> 
> 
> Some questions after reading the DH Hornet book...



Exactly. Meredith requires laminar flow which is difficult to maintain in the divergent duct, not so much in the convergent and, ultimately, is all about eliminating cooling drag - if done right. In your (rather interesting, actually) reference mention is made of the Hornet's cooling flap making the airflow slightly turbulent, however that would only be when the flap was open, typically on the ground, climb and slower speeds, and at high speed the flap would be designed to be flush (or nearly so) with the resulting opening having the appropriate area for achieving Meredith Effect in that situation. What these guys accomplished back then is amazing, frankly. 


This site has a rather good cooling-drag explanation including a Mosquito cooling system cross-section (down a-ways): Contrails ! Radiator aerodynamics


----------



## drgondog (Jul 31, 2016)

First - Cooling Drag is not eliminated by 'Meridith Flow'. The key part of the Mustang design with respect to Meridith flow was the plenum behind the radiator into which the cooling air impinging on radiator heat exchangers flows into the plenum with higher energy and then passed through a squeezed down exit chute at high velocity. At low speed there is not enough thrust to contribute to reducing the effect of Cooling Drag.

At best, the Meridith effect contributes Net Thrust to offset Net Cooling drag.

BTW - "Chuter" seems curiously close to "Shooter" - hopefully by coincidence only.

The Boundary layer improvements (Gutter and lowered intake cowl on the P-51B/D) were made to eliminate the 'rumbling noise' created by the much greater turbulence flowing into the intake cowl before dropping it outside the BL.


----------



## XBe02Drvr (Jul 31, 2016)

drgondog said:


> BTW - "Chuter" seems curiously close to "Shooter" - hopefully by coincidence.



My fellow pilots, in their infinite wisdom, used the term to refer to individuals who would willingly and repeatedly jump out of a perfectly good airplane. Needless to say, the individuals themselves didn't take it as a term of endearment, preferring to be called "jumpers" or skydivers. I went along with this disparagement until I became one and suddenly the tune changed.

Reactions: Informative Informative:
1 | Like List reactions


----------



## drgondog (Jul 31, 2016)

XBe02Drvr said:


> My fellow pilots, in their infinite wisdom, used the term to refer to individuals who would willingly and repeatedly jump out of a perfectly good airplane. Needless to say, the individuals themselves didn't take it as a term of endearment, preferring to be called "jumpers" or skydivers. I went along with this disparagement until I became one and suddenly the tune changed.


 
My father disparaged my choices there also. During WWII he rode it down once behind enemy lines rather than bail, and three times belly landed with really bad battle damage. 

No, the reference to Chuter was also to NeoconShooter and Shooter8..

Reactions: Bacon Bacon:
1 | Like Like:
1 | Like List reactions


----------



## Zipper730 (Jul 31, 2016)

The meredith effect is a ramjet effect?


----------



## XBe02Drvr (Aug 1, 2016)

Zipper730 said:


> The meredith effect is a ramjet effect?



I suppose you could look at it that way. The physicists among us may take umbrage, as it isn't an exact analogy, but yes air gets rammed in the front, it acquires additional energy thru heating, and is ejected at higher velocity thru the tailpipe. And it doesn't acquire useful thrust until the ram velocity achieves a certain threshold.


----------



## pbehn (Aug 1, 2016)

XBe02Drvr said:


> I suppose you could look at it that way. The physicists among us may take umbrage, as it isn't an exact analogy, but yes air gets rammed in the front, it acquires additional energy thru heating, and is ejected at higher velocity thru the tailpipe. And it doesn't acquire useful thrust until the ram velocity achieves a certain threshold.


I would say the thrust was very small maybe enough to compensate for the inlet drag, basically a ramjet where the exhaust gasses were heated by a radiator, the best exponent of the meredith effect also had the most advance inlet design


----------



## Shortround6 (Aug 1, 2016)

The Meridth effect was simple in theory, getting some sort of benefit wasn't that hard. Getting a lot of benefit was.






There is an awful lot going on. 
The Mustang used a large radiator in area. The drag of a radiator is proportional to the speed of the air flowing through it. 
_IF _you can reduce the speed of the air flowing through the radiator to 1/2 the normal airspeed the drag is 1/4 of the full speed drag. 
The large, expanding air duct slowed the airspeed before the air went through the radiator matrix. This reduced the drag. The heated, expanded (higher speed?) air stream was then confined and the speed of the airstream increase further until it exited. 
With the rather modest amount of heat warming the air stream (compared to actually burning fuel in the airstream) the shape/contours?change in cross section have to be carefully planed in order to get any real benefit. Too rapid an increase in cross section or too abrupt an angle increase in the duct the wall and could result in a disrupted airflow before the airstream even gets to the radiator creating excessive drag. If the airflow doesn't hit the radiator at a relatively even airspeed ( core of radiator isn't seeing much higher speed than the edges) then you don't get the advantage of the bigger radiator/slower speed through the matrix.
Getting the airflow speed _through _the radiator matrix right so the air picks up the most heat with the least drag takes a bit of work too. 
Speed too fast and you not only have higher drag, you may not get as high a heat transfer. Speed too slow and you may have not enough engine cooling going on and may not be able to get the airflow back up to the needed speed to generate any thrust ( getting the thrust to actually exceed the drag is the goal (it may not have been achieved) generating a few pounds of thrust (single digit HP) isn't much good if the drag is measured in tens of pounds (or tens of HP) or hundreds. 
The Spitfire ducts weren't long enough and the Mosquito's weren't either.

Reactions: Like Like:
1 | Informative Informative:
2 | Like List reactions


----------



## wuzak (Aug 1, 2016)

Shortround6 said:


> The Spitfire ducts weren't long enough and the Mosquito's weren't either.



I don't think that is correct.

The Spitfire's ducts had too large an opening and too large an exit (at least on the XIV onwards) and only had a two position (IIRC) exit flap.

Its the expansion of the divergent duct (the inlet) and contraction of the convergent duct (the outlet) that matters. I don't know if the Mosquito's had sufficient or not, but its radiator had a totally different shape than the Mustang's, being thin and wide, which means that the length of the duct is, likely, less important.


----------



## Shortround6 (Aug 2, 2016)

This supposed to be the Mosquito's radiator set up. 




It is not the length itself that is the problem but if there isn't sufficient length for a proper expansion and contraction of the duct area/cross section. Too abrupt a change in cross section will cause drag or more drag than the more gradual change.


----------



## wuzak (Aug 2, 2016)

The divergent duct is, arguably, more gradual than that in the P-51.

The convergent duct may be, but the P-51's isn't exactly gradual either, and both have the issue where the outlet is at the bottom, so the duct is less gradual on one side than the other.


----------



## pbehn (Aug 2, 2016)

The Mosquito could have had a much better system to exploit the meredith effect however it involved removing the wing spar, it seems to be the best compromise in the space available.


----------



## drgondog (Aug 2, 2016)

The only advantage the Mosquito Night Fighter had was the ability to find the Mustang and night - and continue to track. Big advantage but its only advantage in an air fight.


----------



## pbehn (Aug 2, 2016)

drgondog said:


> My father disparaged my choices there also. During WWII he rode it down once behind enemy lines rather than bail, and three times belly landed with really bad battle damage.
> 
> No, the reference to Chuter was also to NeoconShooter and Shooter8..


What. was the thinking there, is it safer to belly land than bail out?


----------



## XBe02Drvr (Aug 5, 2016)

pbehn said:


> What. was the thinking there, is it safer to belly land than bail out?


 
Depends on the aircraft, the pilot, and the circumstances. On some aircraft (think Lightning, think Airacobra ), the prospect of getting out of the cockpit without getting hit by the tail was dubious at best. Others weren't so bad. Some aircraft could be gracefully slid onto their belly with relative ease; others were pretty tricky. I know from experience some pilots can transition easily from touching down smoothly with an elevated sightline to doing the same thing with a sightline much closer to the runway. Try checking out a B-52 pilot in his brand new Mooney 201! And the consequences of getting wrong what will probably be your first, last, and only belly landing are not pleasant.


----------



## pbehn (Aug 5, 2016)

XBe02Drvr said:


> Depends on the aircraft, the pilot, and the circumstances. On some aircraft (think Lightning, think Airacobra ), the prospect of getting out of the cockpit without getting hit by the tail was dubious at best. Others weren't so bad. Some aircraft could be gracefully slid onto their belly with relative ease; others were pretty tricky. I know from experience some pilots can transition easily from touching down smoothly with an elevated sightline to doing the same thing with a sightline much closer to the runway. Try checking out a B-52 pilot in his brand new Mooney 201! And the consequences of getting wrong what will probably be your first, last, and only belly landing are not pleasant.


I was asking because it was dd's father and so they may have discussed it


----------



## drgondog (Aug 6, 2016)

pbehn said:


> What. was the thinking there, is it safer to belly land than bail out?


My father made four 'safe' Belly landings - all flak related. When I was contemplating Airborne, he reminded me that "no sane person jumps out of a perfectly flying airplane - and wasn't sure what it would take to get him out of a 'bad flying airplane'. His four were Manston, St. Etiene, FR, Steeple Morden and Steeple Morden. All except the France 'visit' were repaired despite heavy flak damage.

I think the obvious 'go now' sign would be a fire or about to lose something 'important'

Reactions: Like Like:
3 | Like List reactions


----------



## gjs238 (Aug 7, 2016)

drgondog said:


> My father made four 'safe' Belly landings - all flak related. When I was contemplating Airborne, he reminded me that "no sane person jumps out of a perfectly flying airplane - and wasn't sure what it would take to get him out of a 'bad flying airplane'. His four were Manston, St. Etiene, FR, Steeple Morden and Steeple Morden. All except the France 'visit' were repaired despite heavy flak damage.
> 
> I think the obvious 'go now' sign would be a fire or about to lose something 'important'



Great that he saved the plane and it was returned to service!
Was it the same plane each time? (with the exception of St. Etiene)
Was the radiator assembly ripped off each time?
Was the flak encountered while strafing?


----------



## drgondog (Aug 7, 2016)

gjs238 said:


> Great that he saved the plane and it was returned to service!
> Was it the same plane each time? (with the exception of St. Etiene)
> Was the radiator assembly ripped off each time?
> Was the flak encountered while strafing?


No, four separate Mustangs.

WRBbar 44-13591 returned as WRO. 44-13950 WRF was destroyed on the ground by the rest of 354FS Red flight when Priest landed to pick him up. WRBbar 44-14799 returned as YFH (358FS). WRBbar 44-72253 returned as WRL 

All flak, all while strafing or glide bombing

Reactions: Informative Informative:
1 | Like List reactions


----------



## gjs238 (Aug 7, 2016)

drgondog said:


> 44-13950 WRF was destroyed on the ground by the rest of 354FS Red flight when Priest landed to pick him up.



RE: Priest - That's a hero.
A word that's used all too frivolously these days.


----------



## pbehn (Aug 7, 2016)

drgondog said:


> My father made four 'safe' Belly landings - all flak related. When I was contemplating Airborne, he reminded me that "no sane person jumps out of a perfectly flying airplane - and wasn't sure what it would take to get him out of a 'bad flying airplane'. His four were Manston, St. Etiene, FR, Steeple Morden and Steeple Morden. All except the France 'visit' were repaired despite heavy flak damage.
> 
> I think the obvious 'go now' sign would be a fire or about to lose something 'important'


Thanks dd, obviously a belly landing wasnt considered that risky and he saved most of the planes.

Reactions: Like Like:
1 | Like List reactions


----------

