Warbird Information Exchange

Wood, is the original composite.
Cellulose, in a lignin matrix. Wood, does not fatigue.
If it is protected from rot & fungal decay it can last indefinitely.
These masterpieces will be stored and protected like fine art.
Modern adhesives and epoxies will not suffer deterioration like animal based products.
Post war aeroplanes, were simply left out in the weather. No wonder they deteriorated.
I think the limiting factor, that will eventually ground these machines, will be production of suitable fuel. That, or the lack of skilled people to maintain and operate them.

No idea, but I imagine the climate, hangars and not flying in moisture will help a lot for the recent restorations, vice the in service variants that had an especially rough time in hot and humid climates. Found this interesting quote on line:

Jeff Jefford had an article on 'The Mosquito and its Structural Problems in the Far East' in the recent 'RAF Historical Society Journal' No. 74. The conclusion states the following:

"... , while stories of the glue 'breaking down' circulated widely both during the war and after, and there was some factual basis for these, this was not the root cause of the Mosquito's problem. It is true that there were some early manufacturing deficiencies and joints did tend to come apart, but the real problem lay in the swelling and/or shrinkage of the wooden structure, rather than simply inadequate adhesion - although the end result was the same. Despite the remedial action that was implemented, silver-painted, late series Mosquitos, complete with Mod 638, were still grounded for 'defective glued joints' in Singapore as late as 1954, eg VT628 of No 45 Sqn. But was it really defective glue, or a defective joint, or a well-glued well-made joint which had pulled apart through wood shrinkage? It seems self evident that, regardless of the type of glue employed, the colour of the paintwork and the incorporation of Mod 638, the Mosquito was simply unable to stand up to prolonged exposure to the high ambient temperature and humidity of the tropics."

https://ww2aircraft.net/forum/threads/h ... 167/page-2

Well if a Mossie lived in a hangar here in the Northeastern US (Massachusetts) It would experience yearly temperature variations from 0 to 95. Sometimes worse at both ends. And wood expands and contracts in those temperature changes. I wonder if it's the chunks of balsa in between the thin plywood layers that cause the shrinkage and expansion. Plywood doesn't come apart up here - it's used to side houses. Though it has to be protected from moisture. So maybe the glued up plies aren't the cause of the failure.

In the 1940's versions: were the plies cut from the tree by rotating the tree and skimming off the wood?

These new Mossies - where they built in the same way? Balsa filler between thin plies?

Thanks

Service life is based upon condition. You can't assign a calendar time. Condition will depend on environment and care.

Ok how about:

Well built
Northeast US
always hangared
never flown in rain or snow nor ever sitting in rain or snow

The DH Museum had one of their aircraft X-rayed some years ago, I believe it was W4050 the prototype, to investigate integrity and voids.
Although there was never any intention of doing so, as I recall the conclusion was, surprisingly, that the airframe was structurally sound and could have been made airworthy.

Wood itself isn't a composite, but wood-based forms of structure (mallite, plywood etc) are.

My recollection of glue failures on Miles types (for example) were supposedly due in part to incorrect cure during the power-cut restrictions in the winter of 1946/47.

75 years ago, in November 1946, the RNZAF received the first three Mosquito aircraft as part of its post-War re-equipment programme.

Three ex-RAAF aircraft arrived on 8 November with a fourth arriving three days later, after it was delayed at Whenuapai. They were escorted by a Lincoln bomber from RAAF Amberley, via Norfolk Island and Whenuapai.

These were dual-control aircraft to enable RNZAF crews to train before a significant order of over 70 reconditioned ex-RAF Mosquitos were received from England. The No. 75 Squadron RNZAF Unit History noted on 19 November 1946, “Mosquito Conversion Flight commenced flying training programme – flying from 0600 hrs and continued to 1700 hrs.”

Seen here in this photo is the arrival of the first Mosquitos for No. 75 Squadron at RNZAF Station Ohakea. A52-1005 later became NZ2303. Image ref OhG433-46, RNZAF Official.

Loving the different roundels on aircraft delivered the same day!

Different exhaust between the two as well.

Are the temperatures and humidity in the hangar consistent? Alternating high and low temperatures can result in moisture accumulation.

I think it's a pretty safe bet, that if an owner is prepared to part with the lions share of ten million dollars, the asset is going to be protected in a heated hangar.
These aeroplanes can be looked at as an investment. Like fine art, real estate or exotic cars.

Well to be honest I'm interested in wooden airplane longevity in general when built with the general techniques used for the Mossie. So a modern Mossie rebuild is a good source of info.

So it wouldn't be a $10million plane, but the structural questions would be the same.

I believe it was TA634 that was xrayed to see if they could restore it to airworthy.

Anything that is well cared for will last forever.