Spotted at Winton Raceway ..

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Originally Posted by Brian Hjelm

I worked on Merlins, early 1960's. Packard Merlin was a term in common use.

Only minor differences. Some US built engines had US propellor splines, some had British splines. Packard designed ther own supercharger drive. US built engines used US made magnetos and Bendix carburettors. Some Packard superchargers had fewer bolts holding the halves together.

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I did hear that the Mosquito would fly with either British build Merlins or US made ones but with the differences in performance they had difficulty in flying with one of each.

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Originally Posted by Lotz-A-Landies

I did hear that the Mosquito would fly with either British build Merlins or US made ones but with the differences in performance they had difficulty in flying with one of each.

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Aero engines usually do a power test. If the engines were the same Mark then performance should be near enough identical other than slight variations due to tolerances, wear, tuning. This is why they had individual throttles. The flight engineer in Lancasters and Halifax 2's had to balance the engines in flight. One never knows what the ground crews did to keep them flying. They could have mixed and matched parts, used worn parts to maintain squadron readiness, etc. etc. We used to build the hydroplane engines up to the equivalent of Mark 63 and later no matter what the Mark the engine started life as. This was done using an accumulation of spare parts. I imagine war-time airstrips would have had plenty of salvage parts.

Loanrangie, nice pics but............................................... ........







You need a W I D E R lens!! :D:D

Quote:

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Originally Posted by Brian Hjelm

Aero engines usually do a power test. If the engines were the same Mark then performance should be near enough identical other than slight variations due to tolerances, wear, tuning. This is why they had individual throttles.
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I think the problem was that the Mosquito was such a fast, highly stressed aircraft (made out of plywood) and the types of missions they flew, the differences between the two engines were significant at full revs.

What the actual problem was, we'd have to find WWII mosquito aircraftsmen or pilots.

Diana, on a bare engine without the external accessories, and other than the propellor splines and supercharger bolts on some Packard/Continental built engines, there is no way of telling US built Merlins from UK built Merlins other than dismantling and inspecting the supercharger/accessory drive. Packard used their own planetary drive whilst UK engines used a Farman coupling. Engines that had seen a good bit of service may have had carburettors, magnetos, splines, electricals interchanged so these items are not necessarily a clue to origin.