Friday, September 26, 1997

USA-67

 1990-097B


The USA-67 spacecraft was launched in Nov 1990 aboard Shuttle mission STS-38. The Space Command satellite catalog lists the STS-38 flight, 1990-97A/20935, in a 219 x 261 km x 28.5 deg orbit with a recovery date of 1990 Nov 20. It also lists payload USA 67 (1990-97B/20963), cataloged on Nov 27, and two rocket bodies USA 67 R/B(1) (1990-97C/20964) and USA 67 R/B(2) (1990-97D/20965). The orbits of objects 20963-20965 are classified. This is all that is known officially about USA 67.

The Oct 22, 1990 issue of Aviation Week reported that the payload was designated Air Force Project 658, and had a gross weight of 22000 lb. It would be placed in an orbit with an altitude of 400 nautical miles, using an upper stage. The payload carried digital cameras and other sensors.

The Aviation Week article said ``The Defense Dept. satellite ... will focus on the Persian Gulf region to provide both strategic and tactical recon information for Desert Shield air and ground commanders.''. It futher said, referring to the quoted gross weight, ``Existing launch system/upper stage combinations cannot put this much weight into geosynchronous orbit, ...''.

There are a couple of problems with these statements. First, it seems likely that the gross weight quoted includes the upper stage, in which case the mass could be comparable to a TDRS geosynchronous mission. Quoting payload weights inclusive of the upper stage is not unusual in the NASA Shuttle program. So a geosynchronous mission cannot be ruled out on this basis. Secondly, it seemed implausible that a mission dedicated to Desert Shield could be launched so quickly, especially since it had been sitting on the launch pad since before the invasion of Kuwait - the launch was delayed for 4 months due to hydrogen leaks in the Shuttle. Further, the low inclination of 28.5 degrees is barely enough to see Iraq - Baghdad is at 34 degrees north latitude. Why not launch such a payload to a slightly higher inclination?

Therefore, most analysts at the time discounted the Aviation Week story and assumed that the 28.5 degree inclination meant a geosynchronous payload. The presence of two rocket stages was consistent with an IUS launch, which made the most probable payload a MAGNUM signals intelligence satellite like those flown on missions 51-C and STS-33.

However, I later found evidence that only three classified STS/IUS missions were flown: 51-C, 51-J, and STS-33. All other IUS flights are accounted for. Therefore, (as suggested by D-Day a couple of years ago) the STS-38 mission did not fly an IUS. This makes a geostationary payload less likely and the Aviation Week story regains plausibility. Perhaps the AFP-658 payload was modified during the hydrogen leak standdown to observe the Gulf region. It would be interesting to see if there is any evidence that the original July flight plan for STS-38 involved a higher inclination flight. The presence of two rocket bodies implies the use of solid perigee and apogee motors rather than liquid engines (you would only need a single, restartable, liquid engine). We must imagine a large payload and a relatively small pair of kick stages. Presumably these would not be spin stablized as there would be no mechanism to fit a spin table of that size in the Orbiter. The most probable upper stage configuration is therefore something like the SGS-II which involved a pair of Star 48 motors (the same motors used in the spin-stabilized PAM-D). This dual stage rocket was used for Navstar launches on Atlas, and would take up about half the quoted weight. What was the payload? It might be similar to the USA 53 payload launched in Feb 1990 on STS-36, which was later found in an 800 km high orbit, not too far off the claimed 400 naut. mi. for STS-38's payload. However this doesn't square with the two rocket bodies, which were not cataloged for USA 53. The low inclination makes USA 67 hard to see for high latitude observers, explaining why it has not been tracked yet by amateurs.

The UN submission quoted an orbit of 78 x 226 km x 28.5 deg. This represents the orbit of the Shuttle prior to the OMS-2 burn, long before deployment of USA 67, and clearly represents deliberate disinformation.

A new identification for USA 67 emerged in 1996 during an anti-discrimination suit by Hughes employees, when satellites referred to as B-1 and B-2 were discussed. It seems likely that B-1 was USA 40 and B-2 was USA 67. This suggests that USA 67 may have been a version of the SDS-II modified for geostationary use. The court documents reported `launch of the B-2 satellite in Winter of 1990 ... was mistimed, satellite fuel was consumed improperly, leaving little to reach its projected orbit', allegedly as the result of incompetence by managers appointed after the demotion of Hughes' first black manager, who had been in charge of some aspect of the project.

Another interpretation has been advanced in which the second rocket stage is for a second, uncataloged NRO payload, and the SDS-II had LEASAT-style liquid apogee engine.


USA 67 
 

DateTimeEventOrbit  

1990 Nov 16  0656? Deploy from OV-104  217 x 268 x 28.5 
1990 Nov 17  0130?  Solid motor 1 burn  240 x 7500?  
 0131? Burnout 
 0345? Apogee 1  
 0140? PKM sep  220? x 7930? x 28.5 
1990 Nov 17   GEO?  

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