Atlas II Variants - Atlas IIA and IIAS
Credit: © Mark Wade
Status: Retired 2002. First Launch: 1992-06-10. Last Launch: 2002-12-05. Number: 23 . Payload: 7,280 kg (16,040 lb). Thrust: 2,110.60 kN (474,482 lbf). Gross mass: 187,700 kg (413,800 lb). Height: 47.50 m (155.80 ft). Diameter: 3.05 m (10.00 ft). Apogee: 185 km (114 mi).
The Atlas II booster was 2.7-meters longer than an Atlas I and included uprated Rocketdyne MA-5A engines. The Atlas I vernier engines were replaced with a hydrazine roll control system. The Centaur stage was stretched 0.9-meters compared to the Centaur I stage. Fixed foam insulation replaced Atlas I's jettisonable insulation panels.
For the Atlas IIA, RL10A-4 and RL10A-4-1 engines were offered with or without extendable nozzles (Extendible nozzles increased the engines specific impulse, providing additional performance if required). AC-105 / INTELSAT-K, launched 9 June 1992, inaugurated Atlas IIA series flights.
LEO Payload: 7,280 kg (16,040 lb) to a 185 km orbit at 28.50 degrees. Payload: 3,039 kg (6,699 lb) to a GTO. Launch Price $: 90.000 million in 1994 dollars.
Stage Data - Atlas IIA
Stationed at 21.5 deg W. Intelsat K is a single spacecraft purchased to meet critical requirements for Ku-band capacity over the Atlantic region, driven primarily by international broadcasters. The satellite was purchased from GE Americom while under construction (as Satcom K4) and required extensive payload modifications. Spacecraft: Based on GE 5000 series bus.3-axis stabilised using magnetotorquers. Hydrazine propulsion system. Two large solar panels with 1-axis articulation provide 4800 W BOL.4 50 Ahr NiH batteries. Payload: 16 Ku-band transponders which can be configured into 32 high quality television channels. Permits access from ground antennas 1.2 meters dia. and smaller. Launch vehicle put payload into geosynchronous transfer orbit with GCS trajectory option. Positioned in geosynchronous orbit at 21 deg W in 1992-1999 As of 6 September 2001 located at 21.54 deg W drifting at 0.011 deg W per day. As of 2007 Mar 10 located at 160.51W drifting at 11.137W degrees per day.
Commercial TV broadcast. Stationed at 100.79 deg W. Launch vehicle put payload into supersynchronous earth orbit with MRS trajectory option. Positioned in geosynchronous orbit at 101 deg W in 1994-1999 As of 5 September 2001 located at 100.81 deg W drifting at 0.010 deg W per day. As of 2007 Mar 11 located at 91.17W drifting at 0.006W degrees per day.
34 Ku-band transponders for TV. Stationed at 37.48 deg W. Launch vehicle put payload into supersynchronous earth orbit with IFR trajectory option. Positioned in geosynchronous orbit at 37 deg W in 1994-1999 As of 5 September 2001 located at 37.54 deg W drifting at 0.010 deg W per day. As of 2007 Mar 11 located at 37.60W drifting at 0.015W degrees per day.
Mobile communicaitons. Stationed at 101.1 deg W. Launch vehicle put payload into supersynchronous earth orbit with MRS trajectory option. Positioned in geosynchronous orbit at 101 deg W in 1995-1999 As of 5 September 2001 located at 101.01 deg W drifting at 0.024 deg W per day. As of 2007 Mar 11 located at 100.99W drifting at 0.003W degrees per day.
Stationed at 95 deg W; 24 C-band, 24 Ku-band transponders; TV for Caribbean and Central America. Launch vehicle put payload into subsynchronous earth orbit with MRS trajectory option. Positioned in geosynchronous orbit at 95 deg W in 1996-1999 As of 3 September 2001 located at 95.05 deg W drifting at 0.008 deg W per day. As of 2007 Mar 9 located at 132.80W drifting at 0.084W degrees per day.
Geostationary at 64.1E. Launch vehicle put payload into geosynchronous transfer orbit with RAAN Cntl trajectory option. Positioned in geosynchronous orbit at 64 deg E in 1996-1999 As of 5 September 2001 located at 63.98 deg E drifting at 0.003 deg E per day. As of 2007 Mar 10 located at 64.52E drifting at 0.006W degrees per day.
Geostationary at 103.0W. Launch vehicle put payload into supersynchronous earth orbit with IFR/MRS trajectory option. Positioned in geosynchronous orbit at 103 deg W in 1996-1999 As of 4 September 2001 located at 103.06 deg W drifting at 0.009 deg W per day. As of 2007 Mar 11 located at 103.03W drifting at 0.006W degrees per day.
Geostationary at 13.0E. Launch vehicle put payload into supersynchronous earth orbit with IFR/MRS trajectory option. Positioned in geosynchronous orbit at 13 deg E in 1997-1999 As of 3 September 2001 located at 12.95 deg E drifting at 0.024 deg E per day. As of 2007 Mar 4 located at 13.07E drifting at 0.011E degrees per day.
Geostationary at 157.6E. Launch vehicle put payload into geosynchronous transfer orbit with RAAN Cntl trajectory option. Positioned in geosynchronous orbit at 178 deg E in 1997-1999 As of 5 September 2001 located at 178.02 deg E drifting at 0.006 deg W per day. As of 2007 Mar 10 located at 178.19E drifting at 0.002E degrees per day.
Geosynchronous. Stationed over 118.7W Launch vehicle put payload into subsynchronous earth orbit with MRS trajectory option. Positioned in geosynchronous orbit at 119 deg W in 1997-1999 As of 5 September 2001 located at 118.82 deg W drifting at 0.001 deg W per day. As of 2007 Mar 10 located at 42.64E drifting at 4.479W degrees per day.
Classified satellite for the National Reconnaissance Office. It was likely that it was a technology test satellite combining equipment for several future projects, including a prototype COBRA BRASS infrared early warning satellite sensor. The project seemed to have been several years behind schedule (based on the launch vehicle serial number.
The orbit at burnout of the Centaur was 286 km x 25866 km x 27.0 degree. Modification of the orbit to a geostationary 38,300 km circular x 0.0 degree inclination was accomplished by the Marquardt R-4D liquid propellant motor on the HS-601 spacecraft. The satellite carried UHF and EHF transponders for naval communications, and a Ka-band Global Broadcast Service video relay package. Launch mass of 3200 kg dropped to 1550 kg once geostationary orbit was reached. UHF F/O F9 was placed over the Atlantic Ocean in geosynchronous orbit at 174 deg W in 1998; 22 deg W in 1999. Additional Details: here....
US civilian geostationary weather satellite in the Geostationary Operational Environmental Satellite series. It was the first GOES launch on the Atlas II launch vehicle (the Atlas I having been phased out). Built by SS/Loral, based on the FS-1300 bus. It was equipped with one solar panel array and a counter-boom with a solar sail. The satellite carried well as an imaging radiometer and an X-ray detector to monitor solar activity. Stationed at 106 deg W. Positioned in geosynchronous orbit at 104 deg W in 2000. As of 5 September 2001 located at 108.58 deg W drifting at 0.018 deg E per day. As of 2007 Mar 11 located at 135.52W drifting at 0.001E degrees per day.
Launch delayed from June 29. First Advanced Tracking and Data Relay Satellite, using a Hughes HS 601 satellite bus. It included an S-band phased array antenna and two Ku/Ka band reflectors 4.6 meters in diameter. The satellite was launched into a a 167 x 577 km x 28.3 deg parking orbit at 13:05 GMT. The Centaur upper stage made a second burn at 13:21 GMT, releasing the satellite into a subsynchronous transfer orbit of 237 x 27,666 km x 27.0 deg. The satellite's own Primex/Marquardt R4D liquid apogee engine would be used to maneuver the satellite into its final geosynchronous orbit. Stationed at 151 deg W. Positioned in geosynchronous orbit at 150 deg W in 2000. As of 5 September 2001 located at 149.99 deg W drifting at 0.014 deg E per day. As of 2007 Mar 11 located at 145.38E drifting at 3.007W degrees per day.
Military Communications satellite. Launch delayed from October 12 by spacecraft problem. The US Air Force Defense Satellite Communications System satellite was placed by the Centaur upper stage into a 148 km x 898 km x 29.3 deg parking orbit. A second burn put it into a 218 km x 35,232 km x 26.0 deg transfer orbit. The DSCS III B-11 IABS-8 apogee stage, with two Primex R4D liquid apogee engines, circularised the orbit at geostationary altitude on October 21 and then separated from the DSCS.
Launch delayed from July 12, 15 and 22. The GOES-M weather satellite was placed by the Atlas AC-142 Centaur stage into a 164 x 505 km parking orbit and then a super synchronous transfer orbit of 274 x 42275 km x 20 deg. GOES-M was a Loral 1300-series satellite with a single solar array and a solar attitude control sail. Launch mass was 2279 kg and dry mass 1042 kg. The Geostationary Operational Environmental Satellites were developed by NASA-Goddard and were transferred to the NOAA weather agency when operational. In addition to the usual weather imager/sounder, GOES-M carried a new solar soft X-ray imager. Earlier GOES satellites carried simple X-ray collimator detectors, but the new SXI was a full-fledged grazing incidence telescope similar to the SXT on Japan's Yohkoh satellite. The GOES-M satellite was redesignated GOES 12 once in orbit.
GOES 12 was a 980 kg, 973 W spacecraft that carried an IR imager, a "sounder", and an X-ray imager. The IR imager was a Cassegrain telescope covering five wavelength channels, 0.55-0.75, 3.80-4.00, 6.50-7.00, 10.20-11.20, and 11.50-12.50 microns. It provided images covering 3,000 km x 3,000 km every 41 seconds, by scanning the area in 16 square kilometer sections. The "sounder" provided vertical distribution of temperature, moisture and ozone, by passive monitoring in 18 depth-dependent wavelengths. (Long wave IR: 14.71, 14.37, 14.06, 13.64, 13.37, 12.66, and 12.02 microns. Medium wave IR: 11.03, 9.71, 7.43, 7.02, and 6.51 microns. Short wave IR: 4.57, 4.52, 4.45, 4.13, 3.98, and 3.74 microns. There was also another band at visible wavelength 0.7 microns, to provide pictures of cloud tops.) The sounder covered an area of 3,000 km x 3,000 km in about 42 minutes. Another instrument package named SEM (Space Environment Monitor) monitored the energetic electrons and protons in the magnetosphere and the X-rays from the Sun. The above three had been carried on the earlier GOES missions, but GOES 12 carried also an X-ray imager providing an X-ray (about 0.1-1.0 nm wavelength) picture of the solar disk. For some months, the spacecraft was to be on standby, to be activated and moved to a desired longitude. As of 5 September 2001 located at 89.93 deg W drifting at 0.001 deg W per day. As of 2007 Mar 11 located at 74.73W drifting at 0.014E degrees per day.
Launch delayed from October 31, November 13 and 26, 2001 and February 6 due to contract dispute with Boeing over performance of earlier satellites of the series. The Centaur upper stage entered a 167 x 578 km parking orbit and then placed the payload into a 247 x 29135 km x 27.1 deg subsynchronous transfer orbit. NASA's TDRS-I (TDRS-9) data relay satellite used a Boeing BSS-601 bus and was to provide S, Ku and Ka band communications for the Shuttle and International Space Station. After launch a problem developed with the fuel supply from one of the satellite's four propellant tanks. The tanks were paired, so losing one tank cuts the propellant supply in half. A test burn of the General Dynamics R-4D apogee motor raised the orbit to 433 x 29146 km x 26.4 deg on March 11 and a larger perigee burn raised the apogee to geostationary altitude, 429 x 35800 km, on March 13. A further burn on March 19, raised the orbit to 3521 x 35789 km and lowered the inclination to 21.4 deg. A burn on March 25 raised the orbit further to 8383 x 35811 km and lowered inclination to 17.4 deg. As of 2007 Mar 11 located at 62.04W drifting at 0.008W degrees per day.
Delayed from October 29, November 21 and 23. The third and final Advanced Tracking and Data Relay Satellite satellite separated from the Centaur upper stage 30 minutes after launch. This completed the $800 million, three satellite contract. Last launch of the Atlas 2A booster. Flight delayed from October 29, November 21 and 23. As of 2007 Mar 10 located at 40.92W drifting at 0.012E degrees per day.