So if he pulled up to 90 degrees (heaven forbid) the tiedowns resisting rearwards motion experience the same load?
Surely not?
FWIW, my vote is “surely yes”, and for Machdiamond being right.
Question:
What would be the tension on the tiedowns resisting rearwards motion of the cargo if the aircraft pulled up to 90 degrees
and the engine thrust was zero?
Answer:
The tension in the tiedowns would be zero, because then the aircraft and it’s load would both be accelerating downwards (decelerating) at the same rate. Like in an orbiting spacecraft. And in NASA's "vomit comet".
On the other hand, if the aircraft were stationary on the ground it is true that the tiedown tension would increase with pitch-up angle until at 90º the tension would equal the total weight of the load.
But a flying aircraft is not stationary. It behaves exactly as Machdiamond says in Post#545.