Delta-v budget

Delta-v budget (or velocity change budget) is a term used in astrodynamics and aerospace industry for velocity change (or delta-v) requirements for the various propulsive tasks and orbital maneuvers over phases of the space mission.

Sample delta-v budget will enumerate various classes of manoeuvres, delta-v per manoeuvre, number of manoeuvres required over the time of the mission.

In the absence of an atmosphere and landings where the ground is hit with some speed, the delta-v is the same for changes in orbit the other way around: gaining and losing speed cost an equal effort.

Launch/landing budget

*Launch to LEO — this not only requires an increase of velocity from 0 to 7.8 km/s, but also typically 1.5–2 km/s for atmospheric drag and gravity drag
*Re-entry from LEO

Stationkeeping budget

Maneuver		Altitude		Average delta-v per year		Maximum m/s per year
		[km]		[m/s]		[m/s]
station-keeping		50–55
Drag compensation	400–500	<25	<100
Drag compensation	500–600	<  5	<  25
Drag compensation	>600		<   7.5
Attitude control (3-axis)		2–  6
Spin-up or despin		5–10
Stage booster separation		5–10
Momentum wheel unloading		2–  6

Interplanetary budget

Maneuver				Delta-v required
From:		To:		[m/s]
Earth surface	Low Earth Orbit	9300-10000
Low Earth Orbit	Geostationary Transfer Orbit	2500
Geostationary Transfer Orbit	Geostationary Orbit	1500
Geostationary Transfer Orbit (perigee)	Earth escape orbit	700
Earth escape orbit	Low Lunar Orbit	700
Earth escape orbit	Mars Transfer Orbit	600
Low Earth Orbit	Mars surface	4800
Low Earth Orbit	Solar escape	8700
Low Lunar Orbit	Lunar surface	1600
Mars surface	Low Mars Orbit	4100
Mars capture orbit	Mars low-energy transfer orbit	900
Low Mars Orbit	Phobos Transfer Orbit	900
Phobos Transfer Orbit	Deimos Transfer Orbit	300
Deimos Transfer Orbit	Deimos surface	700
Phobos Transfer Orbit	Phobos surface	500

See also

*Tsiolkovsky rocket equation

External links

*Delta V pages at Caltech
*Javascript Delta V calculator