From memory, the LH at NBO had all L/E stowed, sad day for them
Thread drift here but the LH incident was/is totally unrelated to what happened to the 56.
Now a bit rusty here but.....
In that case, the engines in those days were very 'strapped' for power especially at a place like NBO and bleeds off takeoff was reqd.
The F/E had selected the pylon valves (bleeds) closed after start and at the time there were no warning lights on the front P3 panel for L/E position/disagree. (amber and green). The trailing edges deployed, albeit slowly as the EDP's were producing pressure, but without the pneumatics the L/E flaps all remained stowed.
That indication light mod. on the P3 panel came about a result of that accident.