Command module

A command module, cockpit, command pod, or probe core is a part which allows a player to control a vessel. While it is no longer required to choose a command module before building, there must be at least one module operational for a ship to be controllable.

Naming

Various names are used for this type of part. The term command module is, in general, everything which allows a player to control a vessel. Cockpits and command pods can be manned by Kerbals, with cockpits usually placed on planes, and command pods normally placed on rockets. Crew pods or capsules might be also used instead of a command pod. Command modules which cannot be manned are sometimes called probe cores but usually are called command modules as well. The name of a separated stage with a command module will get amended by "Lander" for lander cans, "Probe" for unmanned probe cores, "Rover" for the EAS-1 External Command Seat, and "Ship" for everything else.

Control

All vessels can only be controlled as long as at least one command module on board is operational. Manned command pods need at least one crew member to be functional. Probe command modules consume electric charge and cease to function when the energy of the vessel is depleted. Manned command pods do not operate in similar fashion to probe command modules when missing a crew, and do not drain any electric charge.

All unmanned command modules have SAS except for the Stayputnik Mk. 1. The probe cores have different level of direction holding ability.

Name	Cost	SAS level & capabilities
		0	1	2	3
		Stability Assist ()	Prograde/ Retrograde (/)	Normal/Radial Hold (/)	Target Tracking (/)	Maneuver ()
Probodobodyne RoveMate	800	Yes	No	No	No	No
Probodobodyne Stayputnik	300	No	No	No	No	No
Probodobodyne QBE	360	Yes	No	No	No	No
Probodobodyne HECS	650	Yes	Yes	No	No	No
Probodobodyne OKTO	450	Yes	No	No	No	No
Probodobodyne OKTO2	1 480	Yes	Yes	Yes	No	No
Probodobodyne HECS2	7 500	Yes	Yes	Yes	Yes	Yes
RC-001S Remote Guidance Unit	2 250	Yes	Yes	Yes	Yes	Yes
RC-L01 Remote Guidance Unit	3 400	Yes	Yes	Yes	Yes	Yes
MK2 Drone Core	2 700	Yes	Yes	Yes	Yes	Yes
MPO Probe	9 900	Yes	Yes	Yes	Yes	Yes
MTM Stage	21 500	Yes	Yes	Yes	No	No

On manned modules stability assist is only by kerbonauts available which are pilots. The direction holding capabilities depend then on the experience of the most experienced kerbonaut.

Torque is generated using reaction wheels which drain additional power to operate them.

Prior to 0.20 a command module was always the root part, but since that update, it is possible to build vessels without one. In this case the game will warn the player that the craft is not controllable.

Manning

At the beginning of a flight, only the primary command module will be manned. Since 0.21 the player can change which command pods and passenger compartments are manned before launch. The available crew is selected from the astronaut complex. In earlier versions the only way to get additional crew for a ship was by manually moving Kerbals from another vessel using EVAs.

Each command pod which can be manned and except the seat has a small amount of monopropellant on board to allow refilling EVA suits.

Manned pods cannot be launched without at least one astronaut aboard, which makes unmanned testing a bit more difficult, as it requires a probe to be attached to the pod.

List of command modules

There are nineteen different command modules in the game. Four of them are crew pods designed for use with rockets, five are cockpits designed for planes, seven are probe modules designed for unmanned probes, one for unmanned Mk2 crafts, one is a cupola intended for space stations, and one is an external seat for rovers. The main difference between the different command modules is their outer form, their mass, and their crew capacity, except for the EAS-1 External Command Seat which uniquely cannot have crew assigned to it at launch, create or store science reports, or be the first part of a craft.

The PPD-10 Hitchhiker Storage Container, although a manned module, is not a command module and cannot be used to control a craft even if it is occupied.

Image	Part	Radial size	Cost ()	Mass (t)	Max. Temp. (K)	Tolerance (m/s)	Tolerance (g)	Torque (kN · m)	S.A.S. level	Required Crew/ Power	Capacity (⚡)
	Mk1 Cockpit	Small	1 250 (1 241)	1.28 (1.25)	2 000 (1 100)	40	50	10			50 ⚡ 7.5 MP
	Mk1 Inline Cockpit	Small	1 600 (1 591)	1.03 (1.00)	2 000 (1 100)	40	50	10			50 ⚡ 7.5 MP
	Mk2 Cockpit	Mk2	3 500 (3 482)	2.06 (2.00)	2 500 (1 400)	45	50	15		+	150 ⚡ 15 MP
	Mk2 Inline Cockpit	Mk2	3 500 (3 470)	2.10 (2.00)	2 500 (1 400)	45	50	15		+	150 ⚡ 25 MP
	Mk3 Cockpit	Mk3, Small	10 000 (9 880)	3.90 (3.50)	2 700 (1 500)	50	50	40/40/20		+	500 ⚡ 100 MP
	Mk1 Command Pod	Small, Tiny	600 (588)	0.84 (0.80)	2 200 (1 200)	14	50	5			50 ⚡ 10 MP
	Mk1-3 Command Pod	Large, Small	3 800 (3 764)	2.72 (2.60)	2 400 (1 400)	45	50	15		+	150 ⚡ 30 MP
	Mk1 Lander Can	Small	1 500 (1 482)	0.66 (0.60)	2 000 (1 000)	8	50	3			50 ⚡ 15 MP
	Mk2 Lander Can	Large	3 250 (3 202)	1.515 (1.355)	2 000 (1 200)	8	50	15		+	100 ⚡ 40 MP
	PPD-12 Cupola Module	Large, Small	3 200 (3 188)	1.80 (1.76)	2 000 (1 000)	8	50	9			200 ⚡ 10 MP
	EAS-1 External Command Seat	Radial mounted	200	0.05	1 200	6	50	—			—
	Probodobodyne RoveMate	Small	800	0.15	1 200	12	50	—	0	2.4 ⚡/min (144 ⚡/h)	120 ⚡
	Probodobodyne QBE	Tiny	360	0.07	1 200	15	50	—	0	1.5 ⚡/min (90 ⚡/h)	5 ⚡
	Probodobodyne HECS	Tiny	650	0.1	1 200	12	50	0.5	1	1.5 ⚡/min (90 ⚡/h)	10 ⚡
	Probodobodyne OKTO	Tiny	450	0.1	1 200	12	50	0.3	0	1.2 ⚡/min (72 ⚡/h)	10 ⚡
	Probodobodyne OKTO2	Tiny	1 480	0.04	1 200	12	50	—	2	1.8 ⚡/min (108 ⚡/h)	5 ⚡
	Probodobodyne Stayputnik	Tiny	300	0.05	1 800	12	50	—	—	1.67 ⚡/min (100 ⚡/h)	10 ⚡
	Probodobodyne HECS2	Small	7 500	0.2	2 000	8	50	10	3	3.0 ⚡/min (180 ⚡/h)	1 000 ⚡
	RC-001S Remote Guidance Unit	Small	2 250	0.1	2 000	9	50	0.5	3	3.0 ⚡/min (180 ⚡/h)	15 ⚡
	RC-L01 Remote Guidance Unit	Large	3 400	0.5	2 000	9	50	1.5	3	4.8 ⚡/min (288 ⚡/h)	30 ⚡
	MK2 Drone Core	Mk2	2 700	0.2	2 500	20	50	15/3/3	3	3.0 ⚡/min (180 ⚡/h)	250 ⚡
	MPO Probe	Small	9 900 (9 854)	0.895 (0.395)	2 200	9	50	6	3	3.0 ⚡/min (180 ⚡/h)	1 000 ⚡ 45 LF 55 O
	MTM Stage	Small	21 500 (6 300)	0.795 (0.415)	2 200	12	50	12	2	1.8 ⚡/min (108 ⚡/h)	4 000 ⚡ 3 800 XE