Find that rather hard to believe, can anyone support that ?
It is a scary thought.
I've got an Eastern Airlines Flight Manual that lists the requires for CAT IIIa approaches. The first hint is having "A" "B" or "AB" options on the autopilot pitch channel selector.
-19(?) engines. Rocket ship. Huge improvement over the -15's(?).
Dash 15s had 15,500 pounds of thrust. There were -17 and -17R engines with 900 pounds more thrust than the -15. The -17Rs kicked it up another 1000 pounds during an engine failure with the APR armed.
Then there are the Valsan conversions with -217 or -219 engines. The -219s are running 21,700 pounds of thrust down the runway. Ridden in one of those a couple times, true rocket ship performance.