Originally Posted by
Trumpet_trousers
Remind me again how they solved the crossover problem for side door parachuting on the C-17?
It took several things working together.
1. Floor angle. To get the required floor angle required a specific airspeed and AOA, which required experimenting with different flap deployment angles till they found the right one.
2. Air deflector angle and deflector hole size and pattern. There was lots of experimentation with different air deflector angles and hole sizes and patterns
3. Longer static line. Initially a 10 foot static line extension was added for C-17 only. This added to logistics complications (the Army owned the parachutes, but USAF owned the C-17 unique extensions), so all parachutes were equipped with a 10-foot longer static line regardless of the aircraft being jumped from.
But C-17 has turbofans so the airflow around the fuselage is very different than A400. C-17 never had the ramp jump problems the A400 is (reportedly) having, and C-17 never had the bundle, CDS, and LVAD airdrop problems the A400 is (reportedly) having. C-17 also has dual-row airdrop, which is unique to C-17 and A400 does not have. Don't know if all the A400 problems are due to the giant props on the A400, but that's the single biggest difference between the two aircraft.