Sir, – Aer Lingus was not, "in effect, born out of the Irish Air Corps" (Books, Weekend Review, June 18th). The Martinsyde aircraft, purchased on Michael Collins's authority, did not see service during the Civil War and was subsequently reduced to scrap very soon after Fianna Fáil came into power in 1932. During the Civil War the Military Air Service used other aircraft for leaflet dropping missions, while I doubt if any aircraft ever operated out of Beggar's Bush Barracks. A more accurate view of the relationship between the Air Corps and civil aviation can be obtained by reading my book Military aviation in Ireland 1921-1945. – Yours, etc,