Recently I've been working my way through the PPrune megathread on Concorde: http://www.pprune.org/tech-log/423988-concorde-question-77.h... , in which (somewhere) is a discussion of the control systems. Analog fly-by-wire! A complex set of "synchro" and "resolver" systems connected to op-amps, giving it autostabilisation and autothrottle all the way up to Mach 2. The pilots would just push the throttles full open on the runway and leave them there until it was time to come down.
The F-16 used analog fly by wire, and the F-16's analog computer was very well thought of.[1] Here's what it looks like.[2] All those discrete parts! Note the quadruple redundancy.
AFAIK Concode only uses ~80% thrust on takeoff due to vibrations engines create and risk of overheat. Also fuel gets pumped around to change CG, it is a fascinating piece of machinery.
It's all in that thread :) The 80% limit was only on one engine, due to vortex issues. The others had to be at "100%" and full afterburner to get off the ground. The actual volume of fuel flow for a particular power level was also determined by an analogue computer measuring the inlet air temperature and pressure.
