Regarding your enquiry into the “H-S” of Lord Donegall, Hall-Scott was never a contractor for Liberty V12s, although they built some parts for the prototypes. During the war they built only their own four and six cylinder training plane engines, the A7A and A5A. Afterwards they brought out the L6 (aviation) and LM6 (marine) engines, updated six-cylinder Liberties of 200-225 h.p.), Their first 12-cylinder production engine (in 1939) was the 550 h.p. Defender marine engine (derived from the six-cylinder Invader, the successor to the LM6) which powered so many British MTBs, ASRs and MLs in the first years of the second war.
Interesting, isn’t it, that copies or derivatives of the so-scorned American WWI Liberty should be a mainstay of British (and Russian) land and sea forces 25 years later? (The Russians used them in their tanks, too.)
What price the Rolls-Royce Eagle?
Malvern, Penna, USA J. J. S. Sherman