What makes the SR-71B’s cockpit different?
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A Few Differences
SR-71As were the main variant of the Blackbird, with the SR-71B designed as the trainer variant. Both planes are essentially identical to each other, but where they mainly differ is in the cockpit.
The Control Transfer Panel is unique to the SR-71B variant. It contains four toggle switches and four control transfer indicator lights. The panel is found in both cockpits inside the B model, allowing either crew member to give or take control of the systems on board the aircraft.
Such systems are composed of Navigation, Fuel, Inlet Spike and Forward Bypass, and Autopilot.
In addition, both crew members have an autopilot indicator panel on the right console. The panel shows what autopilot mode was selected by the other person and only illuminates in the cockpit not in control of the autopilot.
If AC power was lost, a press-to-talk emergency intercom system could be activated on the left side via a button. Alert and bailout warning lights can also be found in both cockpits.
Compared to the SR-71A, the SR-71B doesn’t have a Tactical Air Navigation System Control Switch or a liquid nitrogen gauge. Aside from those differences, the cockpits of both models are almost the same.