The early long body 707's (with JT-4A engines) took a hell of a push on the rudder with an outboard failure at rotation
The British ARB (CAA now) insisted on a fully boosted rudder and an increase in tab authority before BOAC could put them on the British register, for that very reason.
In fact I cant remember now but I think there was a difference in the -300 and -400 as well
