See
this post and the following discussion there from nine years ago.
There were only two drops with BMD-1
including crew on the standard P-7 airdrop platform; one with two men inside, the other with the crew in a special cushioned container next to it.
Since then all crewed drops don't use the airdrop platform anymore, but instead the PBS-915/916/950/950U system with:
- chutes that are directly hooked up to the vehicle
- retrorockets for losing speed (PBS-915/916)
- a gas-inflated impact cushion (PBS-950)
- a suspension that
- specially designed seats which can be tilted so you lay on your back (originally only available for driver and gunner).
Chutes slow to 16-23 m/s first, retrorockets slow to an immediate pre-impact velocity of 3.5-5.5 m/s. The bonus thing about the overall design - aside from being able to use the vehicle straight-away after disconnecting the chutes - being that (for BMD-3 and -3M/4) the vehicle doesn't need to be prepped on the tarmac but can drive there completely rigged-and-drop-ready from its base.
The Soviets and Russians continued to use the P-7 platform with the BMD series as well btw. There have only been about 250-300 drops with crewed BMDs in the last 40 years, probably only somewhere around a platoon of troops at any given time in the entire Soviet Army who've done that and likely only a handful of soldiers who've done it twice.