Well, when I went through the training, it went something like this in an oversimplified, blurred-by-forty-years-of-doing-other-things way:
You have a main parachute on your back and a reserve 'chute strapped to your front. The main opens when a fifteen-foot line that is hooked to a wire rope inside the aircraft yanks a "pilot" 'chute out of the bag that the main is packed into. You exit the aircraft from a ramp that is opened and lowered to just below horizontal at the rear of the aircraft. You walk to the end of the ramp and wait until the jump-master tells you to exit at which time you take a few steps and are outside the plane, falling down. You have one hand (right in most cases) wrapped around a D-ring that is a fall-back way to open the main and the other hand on the D-ring that will open the reserve chute if the main fails.
"Combat" level drops - that is to say, ones at the standard altitude developed from WW2 and Korean War experiences - is about 600 feet and the airspeed depends in part on what the stall speed is for the aircraft you're in. Usually, propellor aircraft are best as the drop speed is lower. Practice and training drops are from 1,500 to 1,000 feet. So-called, "HALO" which I think stands for "High altitude low opening" jumps are from higher altitudes and are for specialized highly trained jumpers. Standard paratroop training in the U.S. Army is really aimed at producing World War 2 massed division-sized (or larger) drops, but is equally capable of training troops for battalion and or brigade sized drops.
You are trained to open your reserve if the main doesn't open, and if the reserve fails, to report to the Chief Rigger at the drop zone and complain immediately after landing. Be sure to bring both of your failed 'chutes with you, so he can determine the cause of failure.
As far as Soviet parachute troops regularly or even sometimes jumping without chutes, that is, in my professional military NCO opinion, plain old bull. Once, a few troops, in a desparate attempt to do something then and there viewed as utterly essential to prevent - fill in the blank with their version of the end of civilization as they knew it - maybe; as a program, policy or regular practice? Bull. I don't care what educated source you cite. Produce one - just one - Soviet paratrooper sergeant who says that he and his boys did it and I eat crow. But I doubt that you can find one, even if any are still alive. Nobody's sergeants do that to their troops on a regular basis. Not even Stalin's.
[ June 11, 2005, 07:08 PM: Message edited by: Ike ]