Contract sorted out for the shuttle-Mir docking hardware; NPO Energia will supply a Buran docking mechanism to be mounted on the Rockwell shuttle airlock.
Simulated countdown exercise at the Cape July 20-22 clears the way for the long-awaited Titan-IV-Centaur launch. [Only to have it blocked again by the Vandenberg Titan IV failure...]
Clinton writes to Goldin, saying that NASA's future should be "linked more firmly" to economic competitiveness and "environmental needs", congratulating him on the station redesign, and wishing him "every success in your efforts to restructure NASA".
NASA center directors sign an interesting memo pledging allegiance to Goldin. A few days later, Aaron Cohen quits as JSC director. [Now, mind you, apparently Cohen was planning to leave anyway, so this isn't quite as good a story as AW&ST makes it out to be.]
Commission on airline competitiveness strongly backs a switch to GPS-based navigation.
The Pentagon has voiced strong objections to Inmarsat's plan to broadcast differential-GPS correction data from the Inmarsat 3 satellites. The Clarke-orbit satellites (first launch set for early 1995), will broadcast a GPS-like signal which not only can be used as a GPS ranging signal, but will also carry data identifying ailing GPS satellites... and wide-area differential-GPS corrections obtained from ground stations. Inmarsat points out that there really is no difference between this and the more local differential-GPS corrections that the Pentagon apparently does not object to: the North-America corrections for Inmarsat would come from FAA receiving stations and could be turned off in the event of attack.
The DoD/DoT task force on future civil GPS use hears report suggesting that differential GPS may be significantly easier for terrorists or pranksters to interfere with than plain GPS.
International concern over US control of GPS continues to increase. The Europeans have pointed out that if GPS becomes the universal navigation aid that it has the potential to be, and older systems are then shut down as unnecessary, this would give the US great political leverage. There is talk that GPS cannot become the standard navaid for international civil aviation unless the US signs a binding treaty covering its operation and use.
Atlas flies again, this time successfully, July 19. The payload was a DSCS-3 military comsat, intended to replace the last of the DSCS-2s (which is old and sick). GD is gearing up to try to clear some of the backlog, with a Navy UHF satellite to go in early Sept and an AT&T comsat [on the first Atlas 2AS, I think] in early Dec. Atlas performance this time was essentially perfect, with the payload within 1nmi of the intended transfer orbit.
July 17 Discovery launch scrubbed due to problems with the SRB explosive-nut detonator system. A solid-state switch on the pad, used to arm the detonators, turned itself on about an hour before the scheduled liftoff; it is not supposed to turn on until T-18s, to minimize the chance of accidents. The exact nature of the failure is unclear, although the switch in question did show below-specs performance when tested. This is the first time there has ever been significant trouble in this system. Launch rescheduled for July 24. [No such luck.]
Russia and Kazakhstan continue to squabble over the future of Baikonur/Tyuratam, as problems of poor maintenance, crime, and lousy working and living conditions worsen. Russia is visibly hedging its bets, with construction of a Zenit launch facility underway at Plesetsk and a Proton facility being discussed. Doing Mir 2 entirely from Plesetsk would be awkward with current boosters because of the payload penalty on the "A" boosters used for Soyuz and Progress, but the idea of switching them to Zenit had already been broached for other reasons.
US-Russia argument over the sale of oxyhydrogen engine technology to India resolved: Russia will sell hardware, but not the design and manufacturing technology, and will abide by the Missile Technology Control Regime rules. This is expected to clear the way for resumption of US-Russia talks on space cooperation, which were stalled by the dispute. [On the other hand, India is furious.]
Lockheed-Khrunichev is among the parties relieved by the agreement, because Khrunichev and Salyut recently formed a joint rocket center for Proton marketing, resolving a previous debate about who had the rights to Proton... and Salyut was involved in the sale to India.
P&W sketch possible booster designs using the Russian RD-170 engine. Of particular note is a design for a shuttle SRB replacement, with the usual possibilities for extending it into heavylift vehicles.
FAA plans tests of transmitting differential-GPS corrections through its VOR beacons... using, unfortunately, a data format different from the marine format used by current receivers. [This frankly sounds pretty dumb, but they may have a reason for the change, I suppose. Hmm, perhaps the marine format doesn't include altitude...]
Wisconsin transportation dept. uncovers GPS accuracy degradations while doing differential-GPS tests at Oshkosh; apparently satellite PRN19 is slightly off spec. Trimble (supplier of the survey-grade receivers used) has several other similar reports. The USAF says there's nothing obviously wrong with the satellite. Trimble says that differential GPS is more sensitive than regular GPS, which might explain the difference of opinion. The error is not large, introducing a bias of about 4m.
"Forum" article by Roger Pielke of U of Colorado: "How much does the space shuttle program cost? The answer is not simple..." [Since this is a common debating point in sci.space :-), I'll cover this in some depth...]
NASA's cost tabulations understate the costs slightly, perhaps 10%, because they do not include DoD investment or ASRM. There is endless confusion over constant dollars vs then-year dollars when discussing past costs. [He ends up quoting everything both ways; I'll quote only the 1992-dollars numbers.] Up to FY92, the shuttle cost $79.2G, compared to $92G for the whole Apollo program; the shuttle will pass Apollo by 1996. If FY93 costs are typical, the shuttle total will be $138G by 2005 and $160G by 2010.
If the program had ended at the end of FY92, cost per flight would have been $1.6G. If it averages 8/year to 2005, average cost will be $900M ($825M to 2010). If we assume 4/year -- which is arguably more realistic for a long-term average -- to 2005, it's $1.35G each.
However, a more realistic number is operations costs. Using NASA's official designation of the development program as ending with the fourth flight -- conveniently also the end of FY82 -- development cost was $32.4G, and operational flight rate has been 4.6/year at about $1G each. $1G per flight, and $4.5G/year, is the best estimate of future costs now available; other estimates should be justified in detail.
NASA calls it $414M/flight right now; the discrepancy has two causes. First, they assume that projected flight rates and costs will be realized in practice -- historically a bad assumption. Second, they estimate based only on the current fiscal year, rather than using the full operational history (ten years). Actual costs *might* end up as low as their number, but that's not the way to bet.
Then there are marginal and fixed costs. GAO says the marginal saving of killing one FY93 flight would be about $44M. (Since the flight rate is probably at or near its maximum, talking about the marginal cost of adding a flight is probably meaningless.) The low marginal cost implies high fixed costs; indeed, in FY87 (no launches) the program cost $4G, and in FY88 (one launch) $3.8G. This indicates that messing with the flight rate will not significantly alter total program costs.
Then there is attrition. In the first 50 flights, NASA lost one orbiter, at a replacement cost of about $2.5G. [Remember, this is all 1992 dollars.] At a loss rate of 1 in 50, attrition cost is $50M/flight. But this is dubious: orbiter production is ended, and another loss could well introduce radical policy changes, so this is of interest to future programs but not this one.
Pressure to cut per-flight costs can result in pressure to boost flight rate, possibly hurting reliability. However, given that the annual costs are nearly independent of flight rate, it is better to assess the program based on annual cost, and set flight rates based on other criteria. A complete program assessment should also include schedule performance -- ability to launch and relaunch on schedule -- and operational capability.
[End of Forum article summary.]
Landsat images of midwest flooding, specifically the St. Louis area on 4 July 1988 (drought) and 18 July 1993 (lots and lots of water). [The difference is actually pretty shocking; the rivers are swollen amazingly, and you have to look twice to convince yourself that the two images are to the same scale.] Eosat is providing Landsat images at no cost for disaster recovery. Both Eosat and Spot Image are having an awkward time of it -- they've got intense demand for images of an area that has been just about completely clouded over for weeks! NOAA is experimenting with using data from the military-weather-sat microwave imagers -- which can distinguish dry from wet surfaces -- to do low-resolution (20-50km) flood monitoring even through cloud.
"Every time I inspect the mechanism | Henry Spencer @ U of Toronto Zoology closely, more pieces fall off." | henry@zoo.toronto.edu utzoo!henry