In a previous life I was one of those guys falling out of the OV-10. I say falling out because 4 jumpers (3 if heavily equipped), one at a time, climbed into the fuselage and sat facing aft, between the legs of the one before. The last man in was the stick leader and only had about 2 inches of deck to sit on, held in only by his safety belt with his legs and much of his body actually outside the aircraft.
Ingress to the target was almost always at very low altitude and more than one stick leaders legs struck tree branches. At the IP just prior to the drop zone the pilot would 'pop up' to approximatly 75-80 degrees nose up. The stick leader would be fighting some Gs trying to focus on the green jump light, which was located in a fairly awkward spot and came on at approx 200 feet AGL. At that instant he would release the belt and leave the aircraft. Due to his momentum he would continue his upward trajectory following the aircraft and his static line parachute would actually open underneath him. You haven't lived until you have watched your parachute open below your feet and been somersaulted rather vigorously into proper position for impact (landing) which occured seconds later.
If the conditions were right it was actually possible to swing completely OVER your chute.
The rest of the jumpers would scramble for the door on their backsides and push clear of the aircraft as fast as possible. An important tip was to avoid at all costs being the 4th man as the aircraft would generally run out of 'pop' and into a radar threat environment just as you arrived at the door. A wingover/dive for the ground would soon follow. Many #4 jumpers have literally dove out that door just in the nick of time.
Over in seconds but all in all, a fun way to go to work!
More info on current Bronco events:
OV-10Bronco.Net - Start Page