Juno II

Juno II

Launch of a Juno II
Function	Expendable launch system
Manufacturer	Chrysler for the ABMA
Country of origin	United States
Cost per launch (1985)	US$10.83m
Size
Height	24.0m (78.7ft)
Diameter	2.67m (8.76ft)
Mass	55,110kg (121,500lb)
Stages	3-4
Capacity
Payload to LEO	41kg (90lb)
Payload to Sub-orbital TLI	6kg (13lb)
Associated rockets
Family	Jupiter
Launch history
Status	Retired
Launch sites	LC-5 & LC-26B, CCAFS
Total launches	10
Successes	4
Failures	5
Partial failures	1
First flight	1958-12-06
Last flight	1961-05-24
Notable payloads	See text

Juno II was an American space launch vehicle used during the late 1950s and early 1960s. It was derived from the Jupiter missile, which was used as the first stage.

Development

Rocket motors derived from the MGM-29 Sergeant were used as upper stages—eleven for the second stage, three for the third stage, and one for the fourth stage—the same configuration as used for the upper stages of the smaller Juno I rocket. On some launches to low Earth orbit the fourth stage was not flown, allowing the rocket to carry an additional nine kilograms of payload.

Chrysler was responsible for the overall contract, while Rocketdyne handled the first stage propulsion and Jet Propulsion Laboratory handled the upper stage propulsion.

History

The Juno II was used for 10 satellite launches, of which six failed. It launched Pioneer 3, Pioneer 4, Explorer 7, Explorer 8, and Explorer 11 from Cape Canaveral Launch Complex 5 and Launch Complex 26B.

Date/Time (GMT)	Serial N°	Stages	Pad	Payload	Outcome	Remarks
1958-12-06, 05:44	AM-11	4	LC-5	Pioneer 3	Partial failure	High sub-orbital launch. Lunar probe, failed to reach Moon due to premature first stage cutoff. Radiation experiments successful.
1959-03-03, 05:10	AM-14	4	LC-5	Pioneer 4	Successful	High sub-orbital launch. Lunar probe.
1959-07-16, 17:37	AM-16		LC-5	Explorer S-1	Failure	Pitched over 5 seconds after launch, destroyed by range safety
1959-08-15, 00:31	AM-19B		LC-26B	Beacon 2	Failure	Premature first stage cutoff. Failed to orbit
1959-10-13, 15:30	AM-19A	3	LC-5	Explorer 7	Successful	Reached low Earth orbit
1960-03-23, 13:35	AM-19C	3	LC-26B	Explorer S-46	Failure	Third stage failed to ignite. Failed to orbit
1960-11-03, 05:23	AM-19D	3	LC-26B	Explorer 8	Successful	Reached low Earth orbit
1961-02-25, 00:13	AM-19F		LC-26B	Explorer S-45	Failure	Third stage failed to ignite. Failed to orbit
1961-04-27, 14:16	AM-19E		LC-26B	Explorer 11	Successful	Reached low Earth orbit
1961-05-24, 19:48	AM-19G		LC-26B	Explorer S-45A	Failure	Second stage failed to ignite. Failed to orbit

Specifications

• Total length: 24.0 m
• Orbit payload to 200 km: 41 kg
• Escape velocity payload: 6 kg
• First launch date: December 6, 1958
• Last launch date: May 24, 1961

Parameter	1st stage	2nd stage	3rd stage	4th stage
Gross mass	54,431 kg	462 kg	126 kg	42 kg
Empty mass	5,443 kg	231 kg	63 kg	21 kg
Thrust	667 kN	73 kN	20 kN	7 kN
Isp	248 s (2.43 kN·s/kg)	214 s (2.10 kN·s/kg)	214 s (2.10 kN·s/kg)	214 s (2.10 kN·s/kg)
Burn time	182 s	6 s	6 s	6 s
Length	18.28 m	1.0 m	1.0 m	1.0 m
Diameter	2.67 m	1.0 m	0.50 m	0.30 m
Engine:	Rocketdyne S-3D	Eleven Sergents	Three Sergents	One Sergent
Propellant	LOX/RP-1	Solid Fuel	Solid Fuel	Solid fuel

See also

• Juno I
• PGM-19 Jupiter

External links

• Encyclopedia Astronautica - Juno II