H.Evans, Vickers Against the Odds,Hodder,1978, P.23 has £1.5Mn. Treasury Launch Aid to Viscount, £3.0Mn. Levy recovery - that is that we, the taxpayer came out ahead ("Plowden Report", 1965 had £5.6Mn Aid, £5.41 Mn. Levy recovery by 4/65 on Dart, so that too will have become profitable to us).
Viscount put Vickers-Armstrongs and RR in the commercial business, teaching them how to treat civil customers; its wings from Eastleigh kept Saro in any business, early-1950s.
The Board of Vickers Ltd. then wasted its profit from Viscount by choosing not to seek Launch Aid for the Viscount Major (they resented the 5% Levy on sales and thought they should enjoy the same gift, not loan, that France gave for Caravelle). Vanguard recorded a loss on Vickers accounts of £16.7Mn.