Discussion of the take off capabilities of differently powered aircraft reminds me of the first 747 sent to Mt Pleasant in 1986 after the Tristar had failed to round out from its autoland approach in UK. First 747 down had US engines - we thought it was not going to make it taking off from MPA, and apparently it was even more dramatic at Ascension. All other flight by BA were with RB211 powered aircraft, to the relief of all.