3 pilots -> 2 pilots
 

Once upon a time you had two pilots, an engineer, a navigator and a radio operator. Gradually the numbers came down.

I can see how the 747 went from 3 to 2 - all the gauges moved into glass displays but what caused the step between the Trident, 727 (I'm assuming that's 3 crew?) etc and the 2-pilot 737, DC9 etc? How was the third man removed? :confused:

The DC9 and 73 were designed from the get go as a 2 man cockpit. Back in the late 60s early 70s there was an agreement between the aircraft manufactures and ALPA(I think) which said any aircraft over a certain weight would be 3 man, and under 2 man. You can figure what happened.

ALPA may have had an input (limit clauses et al) but the FAA had a weight limit for two crew ops of (if memory serves)70,000lb. Thus BAC 1-11s for FAA customers had lower AUW/MTOW than CAA aircraft. This was gradually increased & the weights became the same on both sides of the pond.

The 767 was originally set up for 3-crew but the FAA started basing everything on workload and, with EICAS, two crew was deemed to be able to handle it. BTW Ansett & El Al 67s had 3 crew cockpits with an additional EICAS DU for the FE.

A lot has to do with automation. Boeing managed to effectively put a complex engineers panel into the overhead panel by the use of automatic electrical bus bars and load shedding devices. Likewise with hydraulic, pneumatic, fuel and pressurisation.