Editing Mars Express (section)

=== Propulsion ===
The Soyuz/Fregat launcher provided most of the thrust ''Mars Express'' needed to reach Mars. The final stage of the Soyuz, Fregat was jettisoned once the probe was safely on a course for Mars. The spacecraft's on-board means of propulsion was used to slow the probe for Mars orbit insertion and subsequently for orbit corrections.<ref name="ref1" />

The body is built around the main propulsion system, which consists of a [[Bipropellant rocket|bipropellant]] 400 [[Newton (unit)|N]] main engine. The two 267-liter propellant tanks have a total capacity of 595&nbsp;kg. Approximately 370&nbsp;kg are needed for the nominal mission. Pressurized helium from a 35-liter tank is used to force fuel into the engine. Trajectory corrections will be made using a set of eight 10 N thrusters, one attached to each corner of the spacecraft bus. The spacecraft configuration is optimized for a Soyuz/Fregat, and was fully compatible with a [[Delta II]] launch vehicle.