Editing Soyuz (spacecraft) (section)

=== Reentry procedure ===
The Soyuz uses a method similar to the 1970s-era [[United States]] [[Apollo command and service module]] to deorbit itself. The spacecraft is turned engine-forward, and the main engine is fired for deorbiting on the far side of Earth ahead of its planned landing site. This requires the least propellant for [[Atmospheric entry|reentry]]; the spacecraft travels on an elliptical [[Hohmann transfer orbit]] to the entry interface point, where atmospheric drag slows it enough to fall out of orbit.

Early Soyuz spacecraft would then have the service and orbital modules detach simultaneously from the descent module. As they are connected by tubing and electrical cables to the descent module, this would aid in their separation and avoid having the descent module alter its orientation.{{Citation needed|date=October 2018}} Later Soyuz spacecraft detached the orbital module before firing the main engine, which saved propellant. Since the [[Soyuz&nbsp;TM-5]] landing issue, the orbital module is once again detached only after the reentry firing, which led to (but did not cause) {{Citation needed|date=July 2024}}emergency situations of [[Soyuz&nbsp;TMA-10]] and [[Soyuz TMA-11|TMA-11]]. The orbital module cannot remain in orbit as an addition to a space station, as the airlock hatch between the orbital and reentry modules is a part of the reentry module, and the orbital module therefore depressurizes after separation.

Reentry firing is usually done on the "dawn" side of the Earth, so that the spacecraft can be seen by recovery helicopters as it descends in the evening twilight, illuminated by the Sun when it is above the shadow of the Earth.{{Citation needed|date=October 2018}} The Soyuz craft is designed to come down on land, usually somewhere in the deserts of Kazakhstan in Central Asia. This is in contrast to the early United States crewed spacecraft and the current SpaceX Crew Dragon, which splash down in the ocean.