In a history of British Midland by B.G. Cramp, the short "time between overhaul" interval of the Merlins is mentioned.
Midland bought the aircraft "on the cheap" from Overseas Aviation, then found that they were costly to maintain.
Was the Merlin a high-performance military power plant, unsuited to commercial operations?
And was it particularly unreliable in the Argonaut?
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