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Satellite Propulsion

How Satellite Propulsion Systems Work

A satellite or spacecraft orbiting the earth or traveling through the solar system encounters very small forces. For this reason, many satellite propulsion systems must deliver very precise ``impulse bits'' in order to accurately control the position or attitude of these objects. Reliability is of utmost importance in these systems since there is normally no real opportunity to service them over their entire lifetime. High performance is also a must; higher Isp systems provide additional on-orbit lifetime or the capability to increase the "payload" portion of the spacecraft. Traditionally, chemical propulsion systems using monopropellant (single fluid) or bipropellant (two fluid) liquid thrusters have been employed for these applications. However, the growth in spacecraft power has led to the use of higher energy electric propulsion (EP) systems for many modern missions. Arcjet thrusters heat a working fluid such as ammonia gas to very high temperatures by flowing the gas through a spark between two closely-spaced electrodes. More recently, ion thrusters have seen service on commercial spacecraft. These thrusters operate by accelerating heavy ions created in a plasma inside the device. Hall effect thrusters work on similar principles; these devices are the focus of many current studies.

Details of Various Satellite Propulsion Systems

• TRW
  • Variable Thrust Engine
  • DACS
  • MRE 0.1
  • MRE 1
  • MRE 4
  • MRE 5
  • MRE 15
• Atlantic Research Corporation
  • Leros 1R
  • Leros 2
  • Leros 2R
  • Leros 20
  • Leros 20H
  • Leros 20R
• Daimler-Benz
  • CGT 1
  • CHT 0.5
  • CHT 1
  • CHT 2
  • CHT 5
  • CHT 10
  • CHT 20
  • CHT 400
  • HAJ 1
  • S10/1
  • S10/2
  • S4
  • S400/1
  • S400/2
• Kaiser Marquardt
  • Bipropellant Thrusters
• Aerojet Rocketdyne
  • ACE Propulsion System
  • Arcjet Systems
  • Athena Orbit Adjust Module
  • Centaur Rocket Modules
  • Electrothermal Hydrazine Thruster
  • Hall Current Thruster
  • Iridium Thruster Modules
  • Pulsed Plasma Thruster

Comparison Tables of Various Engines

Chemical Propulsion Systems

Make	Model	Thrust	Isp (s)	Propellant(s)	Weight	Applications
TRW	VTE	130-1300 lbf	275-310 sec	NTO/MMH	15 lb	LMDE, Delta
	MRE 0.1	0.8 N	216 sec	Hydrazine	0.5/0.9 kg	Attitude Control
	MRE 1	5 N	210-220 sec	Hydrazine	1.8 lbm	Pioneer
	MRE 4	18 N	217 sec	Hydrazine	0.5 kg	Attitude control
	MRE 5	36 N	232 sec	Hydrazine	1.5 kg	Attitude control
	MRE 15	86 N	228 sec	Hydrazine	1.1 kg	Station Keeping/Attitude control
Atlantic Research Corp.	Leros 1R	110 lbf	320 sec	MON3/Hydrazine	8.3 lbm	Orbit Insertion
	Leros 2	125 lbf	312 sec	MON3/MMH	7.5 lbf	Orbit Insertion
	Leros 2R	125 lbf	316 sec	MON3/MMH	8.3 lbf	Orbit Insertion
	Leros 20	5 lbf	293 sec	MON3/MMH	1.25 lbm	Attitude Control
	Leros 20H	5 lbf	300 sec	MON3/Hydrazine	0.9 lbm	Attitude Control
	Leros 20R	5 lbf	307 sec	MON3/MMH	1.25 lbf	Attitude Control
Daimler-Benz	CHT 0.5	0.5 N	2230 m/s	Hydrazine	195 g	Attitude Control
	CHT 1	1 N	2230 m/s	Hydrazine	377 g	Attitude Control
	CHT 5	5 N	2234 m/s	Hydrazine	220 g	Attitude Control
	CHT 10	10 N	2260 m/s	Hydrazine	240 g	Attitude Control
	CHT 20	20 N	2300 m/s	Hydrazine	360 g	Attitude Control
	CHT 400	400 N	2240 m/s	Hydrazine	325 g	Attitude Control
	S 10/1	10 N	2815 m/s	MON/MMH	350 g	Attitude Control
	S 10/2	10 N	2860 m/s	MON/MMH	310/530 g	Attitude Control
	S 4	4 N	2795 m/s	MON/MMH	290 g	Attitude Control
	S 400/1	400 N	2972 m/s	MON/MMH	2.8 kg	Orbit Insertion
	S 400/2	400 N	3120 m/s	MON/MMH	3.4 kg	Orbit Insertion

Liquid Engines : Advanced Systems