Whilst the Tristar gets several mentions here, it’s interesting to point out that in the UK nobody failed the 1179 type written exam on the Tristar as RR had financial problems and needed to sell engines. Nobody passed the 1179 exam until the 3rd attempt on the 727 whilst Dan Air and Boing tried top get it onto the British register as it was in competition with the Trident. Lears had to be put onto the Irish register as the ARB said no to curved windscreens as it was in competition with the 125. Good old British politics and aviation.