| VALIGN=TOP>||
| TV-0
(8 Dec 1956) Viking No. 13, a liquid-propellant single-stage rocket redestimated TV-0 and fired as the first Vanguard test vehicle. | VALIGN=TOP>Primary: to evaluate the performance of the internal telemetry system, to evaluate the launch complex, and to become familiar with the operations, range safety, and tracking systems of the AFMTC rocket range.
Secondary: to test the Vanguard Minitrack transmitter and to evaluate the coasting.-flight attitude control system. | VALIGN=TOP>All objectives met except evaluation of coasting-flight attitude control. During powered flight, the performance of all components was either satisfactory or superior. Vehicle reached an altitude of 126.5 mi and range of 97.6 mi. Rocket-borne instrumentation and telemetry systems performed excellently; ground instrumentation coverage adequate. | VALIGN=TOP>
| TV-1
(l May 1957) Two-stage test vehicle. lst stage, the Viking no. 14 slightly modified for Van guard objectives. 2d stage a prototype solid-propellant Vanguard 3d stage. 2d-stage payload, an instrumented nosecone. | VALIGN=TOP>Primary: to flight-test the Vanguard 3d-stage prototype for spinup, separation, ignition, and propulsion and trajectory performance.
Secondary: further evaluation of ground- handling procedures, techniques, and equipment and inflight instrumentation and equipment. | VALIGN=TOP>All test objectives met. Flight operation and performance of all powerplant systems very good. The vehicle was properly controlled throughout flight to an altitude of 121 mi and range of 451 mi. | VALIGN=TOP>
| TV-2
(23 Oct 1957) Vanguard prototype consisting of a live 1st stage, a simulated hut inert 2d stage, and an inert 3d stage. | VALIGN=TOP>Primary: to evaluate the Vanguard launch system and the flight performance of the 1st-stage propulsion system, the 2d-stage retrorocket system, and the 3d-stage spinup system and to obtain data on the 1st- and 2d-stage structural characteristics.
Secondary: to evaluate equipment, test, pro procedures, 1st-stage handling, and the SHF (C-band) beacon and radar equipment. | VALIGN=TOP>All test objectives met. Performance of all components throughout flight superior. This test confirmed that the 1st stage operated properly at altitude, conditions were favorable for successful separation of 1st and 2d stages, launch stand clearance for the condition of low surface winds was no problem, there was structural integrity throughout flight. Test also demonstrated dynamic compatibility between control system and structure. | VALIGN=TOP>
| TV-3
(6 Dec 1957) First complete Vanguard test vehicle with three live stages. | VALIGN=TOP>Primary: to launch into orbit a minimal (6.4-in., 4-lb.) satellite to determine atmospheric density and the shape of the earth. To evaluate satellite thermal design parameters and to check the life of solar cells in orbit.
Secondary: to test and evaluate all stages and systems of the vehicle. This was to have been the first flight firing of the 2d-stage propulsion system and of the complete Vanguard guidance and control system. | VALIGN=TOP>Less than one see after liftoff, the 1st-stage engine lost thrust because of improper engine start. Vehicle settled hack on launch stand and exploded. | VALIGN=TOP>
| TV-3BU
(5 Feb 1958) Identical to TV-3. | VALIGN=TOP>Same as those of TV-3. | VALIGN=TOP>After 57 sec. of normal flight, a control system malfunction caused loss of vehicle attitude control. Vehicle broke up only after an angle of attack of at least 45° had been exceeded. | VALIGN=TOP>
| TV-4
(17 Mar 1958) Identical to TV-3BU. | VALIGN=TOP>Same as those of TV-3BU. | VALIGN=TOP>Placed Vanguard I, totaling 57 lb. (a 4-lb. payload and the 53-lb. 3d-stage motor case), in orbit originally expected to last up to 2,000 years (later estimate, 240 years). Initial orbit had apogee of 2,465 mi., perigee of 406 mi., and period of 134 min.
Guidance system produced an overall error of less than 1° in satellite injection angle. First use of solar cells to supply power for satellite instruments. | VALIGN=TOP>
| TV-5
(28 Apr 1958) Final test vehicle, differing from a production satellite launching vehicle (SLV) only in the greater degree of instrumentation. | VALIGN=TOP>Primary: to launch into orbit a fully instrumented 20-in., 21.5 lb. "x-ray and environmental" satellite. This satellite was to study maximum variations in the intensity of solar x-ray radiation in the l to 8 A wavelength bands and to make certain space environment measurements.
Secondary: to verify the performance of the complete vehicle. | VALIGN=TOP>Flight normal through 2d-stage burnout, but 2d-stage shuTD valign=topown sequence was not completed electrically, which prevented arming of the coasting-flight control system and separation and firing of 3d stage. 2d stage performance below nominal, but combined 1st- and 2d-stage performance somewhat better than nominal. | VALIGN=TOP>
| VALIGN=TOP>||
| SLV-l
(27 May 1958) First production satellite launching vehicle. | VALIGN=TOP>To launch into orbit a fully instrumented, 20-in., 21.5-lb Lyman-alpha satellite. This satellite was to study solar Lyman-alpha radiation and to make certain space environment measurements; it was identical to the x-ray satellite of TV-5 except that it covered the 1100 to 1300 A wavelength hands. | VALIGN=TOP>Successful operation and performance achieved throughout flight, except at 2d- stage burnout. At that time, a disturbance caused loss of attitude reference to the pitch gyro so that the remainder of the flight was controlled to a false reference. Third stage launched at an angle of approximately 63° to the horizontal, thus precluding a satisfactory orbit. | VALIGN=TOP>
| SLV-2
(26 June 1958) | VALIGN=TOP>Same as the primary objectives of TV-5. | VALIGN=TOP>Second-stage propulsion system shut down after 8 sec of burning, so that the velocity was low and the 3d stage was never armed for firing. As a normal result of the premature shuTD valign=topown, 2d-stage propellant tank pressures exceeded design values, proving the structural integrity of the tankage. | VALIGN=TOP>
| SLV-3
(26 Sep 1958) | VALIGN=TOP>To launch into orbit a 20-in., 23.3-lb "cloud cover" satellite. This satellite was to measure the global distribution and movement of cloud cover and to contribute to the basic knowledge of the earth's energy budget. | VALIGN=TOP>Flight normal (or better) in all respects, except that 2d-stage performance was well below minimum predicted. Burn-out 3d stage and satellite reached an altitude of shout 265 mi, but the velocity was about 250 fps short of the 25,000 fps required to orbit. The satellite was presumably destroyed during atmospheric reentry some 9,200 mi downrange. | VALIGN=TOP>
| SLV-4
(17 Feb 1959) | VALIGN=TOP>To launch into orbit a 20-in., 25.7-lb "cloud cover" satellite practically identical to that of SLV-3. | VALIGN=TOP>Placed Vanguard II, totaling 71.5 lb (23.7- 1b. payload and 47.08-lb 3d-stage motor case), in an orbit expected to last at least 200 years. Initial orbit had apogee of 2,063 mi, perigee of 346 mi., and period of 125.9 min. Guidance system produced a negligible overall error in injection angle of 0.02° 0.2°. | VALIGN=TOP>
| VALIGN=TOP>||
| SLV-5
(13 Apr 1959) | VALIGN=TOP>To launch into orbit a fully instrumented 13-in. diameter magnetometer satellite and an expandable (30-in.) aluminum sphere. The satellite was to determine if the predicted Stormer-Chapman ring current existed and to improve knowledge of the earth's magnetic field. The expandable sphere was to supply information on upper air density. | VALIGN=TOP>Pitch attitude control of 2d-stage lost during 1st-stage separation. Resulting tumbling motion in the pitch plane aborted the flight. | VALIGN=TOP>
| SLV-6
(22 June 1959) | VALIGN=TOP>To launch a 20-in. diameter, 23.8-lb "radiation balance" satellite into an orbit with a relatively high inclination (about 48) to the equator. This satellite was to measure the direct radiation of the sun, the radiation reflected from the earth, and the longwave radiation emitted by the earth and its atmosphere. | VALIGN=TOP>There was a rapid decay of tank pressures immediately after 2d-stage ignition. Abnormally low flow rates and chamber pressures resulted, accompanied by combustion instability. About 40 sec later, the helium sphere exploded from unrelieved buildup of pressure by the beat generator. The trajectory was accurately modified from a launch azimuth of 100° to a flight azimuth of about 48° by use of inflight roll programming just after launch. | VALIGN=TOP>
| TV-4BU
(18 Sep 1959) This vehicle incorporated the Allegheny Ballistics Laboratory X248 A2 solid-propellant motor as the 3d stage in place of the Grand Central motor used in previous Vanguard vehicles. | VALIGN=TOP>To launch into orbit a fully instrumented 52-lb "magnetometer, x-ray, and environmental" satellite. This payload combined the scientific objectives of the TV-5 and SLV-5 satellites. | VALIGN=TOP>Placed Vanguard III, totaling 94.6 lb (52.25-lb payload and 42.5-lb 3d-stage motor case), in an orbit expected to last at least 50 years. Initial orbit had apogee of 2,326 mi, perigee of 317 mi., and period of 130 min. Guidance system produced a negligible overall error in injection angle of 0.05° 0.2°. | VALIGN=TOP>
| VALIGN=TOP>||
| Jupiter C
(3l Jan 1958) | VALIGN=TOP>To launch into orbit an 18.13-lb "cosmic ray" satellite. | VALIGN=TOP>Placed Explorer I (totaling 30.8 lb, including the 18.13-lb satellite) in an orbit expected to last 3-5 years. Initial orbit had apogee of 1,573 mi., perigee of 224 mi, and period of 114 min. Scientific instrumentation confirmed predicted cosmic radiation levels up to 600-mi. altitude, measured frequency of impacts and size of micrometeoroids, provided information on earth's bulge and gravity, obtained data on atmospheric density at extreme altitude, and confirmed success of method to control temperature of satellite's interior. Count rates above 600-mi. altitude were very irregular, later found to be the result of very intense trapped radiation about the earth. | VALIGN=TOP>
| Jupiter C
(5 Mar 1958) | VALIGN=TOP>To launch into orbit an 18.5-lb "cosmic ray" satellite similar to Explorer I and known as Explorer II. | VALIGN=TOP>Failed to orbit. Last stage did not ignite. Flight time 885 Sec. | VALIGN=TOP>
| Jupiter C
(26 Mar 1958) | VALIGN=TOP>To launch into orbit a payload almost identical to Explorer II. | VALIGN=TOP>Placed Explorer III in an orbit that lasted until 28 June 1958. Initial orbit had apogee of 1,740 mi, perigee of 119 mi, and period of 115.8 min. Scientific instrumentation added to data acquired by Explorer I. | VALIGN=TOP>
| Jupiter C
(26 July 1958) | VALIGN=TOP>To launch into orbit a 25.8-lb payload carrying two Geiger-Mueller counters, two scintillation counters, and internal temperature measurements transmitted by sub- carrier center frequency shift. | VALIGN=TOP>Placed Explorer IV in orbit. Initial orbit had apogee of 1,373 mi, perigee of 163 mi, and period of 110 min. Measured cosmic rays and trapped radiation over a wide range of levels and energies. Also explored a far greater volume of space as regards latitude and altitude than Explorers I and III. Collected data on trapped electrons resulting from Argus high-altitude nuclear explosions. | VALIGN=TOP>
| Jupiter C
(24 Aug 1958) | VALIGN=TOP>To launch into orbit a duplicate of Explorer IV to be known as Explorer V. | VALIGN=TOP>Failed to orbit. At 1st-stage separation, the booster rammed the instrument compartment. Flight time, 659 sec. | VALIGN=TOP>
| Jupiter C
with "apogee kick" 5th stage added (22 Oct 1958) | VALIGN=TOP>To launch into orbit a high-visibility balloon (9.26-lb. 12-It diameter when inflated), to provide high-altitude atmospheric- density data and to serve as a radar target. | VALIGN=TOP>Failed to orbit. Rotational spin vibrations of the cluster caused the payload to drop off at 112 sec. | VALIGN=TOP>
| Juno II
(16 July 1959) | VALIGN=TOP>To launch into orbit a multiple-experiment satellite and double-truncated cone (91.5 lb). | VALIGN=TOP>Failed to orbit. At liftoff the vehicle deviated sharply to the left and was destroyed at 5 1/2 sec after liftoff. Failure of the guidance inverter caused open loop drift of the control system. | VALIGN=TOP>
| Juno II
(14 Aug 1959) | VALIGN=TOP>Same as attempt of 22 Oct 1958. | VALIGN=TOP>Failed to orbit. | VALIGN=TOP>
| Juno II
(13 Oct 1959) | VALIGN=TOP>Same as attempt of 16 July 1959. | VALIGN=TOP>Placed Explorer VII in orbit. Initial orbit had apogee of 681 mi, perigee of 345 mi, and period of 101.3 min. | VALIGN=TOP>
3. IGY Satellite Launches
| VALIGN=TOP>
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| 1957
Sputnik I 2 1957 Alpha
(4 Oct 1957) Sputnik II 2 1957 Beta (3 Nov 1957) | VALIGN=TOP>|||||
| 1958
Explorer I 1958 Alpha
(31 Jan 1958) Explorer II
(5 Mar 1958) Vanguard I 1958 Beta
(17 Mar 1958) Explorer III 1958 Gamma
(28 Mar 1958) Vanguard Test Vehicle 5
(28 Apr 1958) Sputnik III2 1958 Delta
(15 May 1958) Vanguard SLV-1
(27 May 1958) Vanguard SLV-2 (26 Jun 1958) | VALIGN=TOP>Cosmic rays Meteoroid erosion
Temperatures Meteoric dust Meteoroids
Temperatures Cosmic rays
Temperature Cosmic rays Meteoroid erosion
Temperatures Solar x-rays
Environmental Lyman-alpha
Environmental Solar x-rays
Environmental | VALIGN=TOP>In orbit
Failed to orbit
In orbit
28 Jun 1958
Failed to orbit
Failed to orbit
Failed to orbit | VALIGN=TOP>33.3
34 33.4 | VALIGN=TOP>24.4
406 119 | VALIGN=TOP>1,573
2,465 1,740 | VALIGN=TOP>
| VALIGN=TOP>
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| Explorer IV
1958 Epsilon
(28 Jul 1958) Explorer V
(24 Aug 1958) Vanguard SLV-3
(26 Sept 1958) Pioneer I 1958 Eta 1
(11 Oct 1958) Explorer VI 3 (22 Oct 1958) | VALIGN=TOP>Trapped radiation
Trapped radiation
Cloud cover 12. ft inflatable sphere | VALIGN=TOP>23 Oct 1958
Failed to orbit
Failed to orbit Failed to orbit | VALIGN=TOP>50.3 | VALIGN=TOP>163 | VALIGN=TOP>1,373 | VALIGN=TOP>
| Pioneer II (at 983 mi, 3d stage failed to ignite)
(8 Nov 1958) | VALIGN=TOP>|||||
Pioneer III 1958 Theta
(6 Dec 1958) Project Score 1958 Zeta
(18 Dec 1958)
1959 Luna I2 1959 Mu 1
(2 Jan 1959) Vanguard II 1959 Alpha
(17 Feb 1959) Discover I 1959 Beta
(28 Feb 1959) Pioneer IV 1959 Nu l
(3 Mar 1959) Discoverer II 1959 Gamma (13 Apr 1959) | VALIGN=TOP>Cloud cover Internal
temperature | VALIGN=TOP>In orbit | VALIGN=TOP>32.8 | VALIGN=TOP>346 | VALIGN=TOP>2,063 | VALIGN=TOP>
| VALIGN=TOP>
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| Vanguard
SLV-5
(13 Apr 1959) Vanguard SLV-6
(22 Jun 1959) Explorer
(18 Jul 1959) Explorer VI3 1959 Delta
(7 Aug 1959) Discoverer V 1959 Epsilon
(13 Aug 1959) Explorer
(14 Aug 1959) Discoverer VI 1959 Zeta
(19 Aug 1959) Luna II2 1959 Xi 1
(12 Sept 1959) Vanguard III 1959 Eta
(18 Sept 1959) Luna III2 1959 Theta
(4 Oct 1959) Explorer VII 1959 Iota
(13 Oct 1959) | VALIGN=TOP>30.in. inflatable
sphere
Magnetometer Earth energy
balance Duplicate of
Explorer VII Duplicate of
ExplorerVI Magnetometer Solar x-ray Lyman-alpha
Environmental Micrometeoroid Cosmic rays Heavy nuclei Earth energy balance Solar x-ray Lyman-alpha Radio signals Ground studies | VALIGN=TOP>Failed to orbit
Failed to orbit
Failed to orbit
Failed to orbit
In orbit In orbit | VALIGN=TOP>33.3 50.3 | VALIGN=TOP>317 345 | VALIGN=TOP>2,326 681 | VALIGN=TOP>
| Discoverer VII
1959 Kappa
(7 Nov 1959) Discoverer VIII 1959 Lambda (20 Nov 1959) | VALIGN=TOP>
1 Orbit figures are approximate.
2 U.S.S.R.
3
Two payloads were named Explorer VI: an IGY payload that failed
to orbit 22 Oct 1958 and a post-IGY experiment launched successfully
7 Aug 1959.