Going Public - GPS Declassified: From Smart Bombs to Smartphones - page 96

providing continuous data to multiple location-based applications running
simultaneously.
Such connectedness was undreamed of in the mid-1980s, but the advance
of semiconductor technology and miniaturization of electronic devices was
underway. After the ti-4100, the size and cost of gps receivers began the famil-
iar downward curves associated with most electronic products, but a delay in
completing the constellation itself slowed the expansion of gps applications
to other uses, particularly navigation.
A Major Malfunction
The February 1980 gao report warned about a potential problem that could
knock the gps program off schedule and did so in such a deadpan manner that
reading it today is rather chilling: “Space Shuttle problems could also jeopar-
dize dod's plan to have navstar fully operational by 1987.” 54 The catastrophic
failure of the space shuttle Challenger seventy-three seconds into its flight on
January 28, 1986, undoubtedly exceeded the concerns gao had in mind. It was
the twenty-ifth shuttle mission, officially designated sts- 51- l. Although rocket
launches routinely experienced technical problems and delays, shuttle mis-
sions had become routine—considered safe enough to add schoolteacher
Christa McAuliffe to the Challenger crew. Starting with two launches in 1981,
nasa successfully launched three missions in 1982, four in 1983, five in 1984,
and nine in 1985. Only ten days before the disaster, on January 18, Columbia
(which later disintegrated on reentry on February 1, 2003) had completed a
six- day mission. 55
The Air Force had planned to launch two dozen Block ii satellites aboard
the shuttle by 1987. Recall, however, that funding cuts in 1980 and 1981 trimmed
the constellation size to eighteen and added a year to the schedule. The eighth
through eleventh Block i satellites, not designed for the shuttle, flew aboard
Atlas rockets from 1983 to 1985. A twelfth Block i satellite, which was removed
from the launch schedule and converted into a prototype Block ii satellite for
test purposes, resides today at the San Diego Air & Space Museum and is the
only gps satellite on public display. 56 The grounding of shuttle flights after the
Challenger disaster slowed the gps launch schedule by about two years as the
Air Force developed plans to use a new “medium launch vehicle” called Delta
II for the first eight Block ii satellites. 57 Although it was a new design at the
time, the Delta II rocket, as well as launch pads 17a and 17b at Cape Canav-
eral, traced their lineage directly to the Air Force's thor intermediate- range