| Attempt
|
Planned
|
Result
|
Turnaround
|
Reason
|
Decision point
|
Notes
|
|---|
| 1
|
10 Apr
1981,
7:00:00 am
|
Scrubbed
|
−
|
Technical
|
(T−18 minutes)
|
Timing problem in one of Columbia's general purpose IBM System/4 Pi computers. A software patch was installed to correct. |
| 2
|
12 Apr
1981
7:00:04
|
Success
|
2 days
0 hours
0 minutes
|
|
|
|
Not only was this the first launch of the Space Shuttle, but it marked the first time that solid-fuel rockets were used for a NASA crewed launch (although previous systems had used solid-fuel motors for their escape towers or retro rockets). STS-1 was also the first U.S. crewed space vehicle launched without an uncrewed powered test flight. The STS-1 orbiter, Columbia, also holds the record for the amount of time spent in the Orbiter Processing Facility (OPF) before launch – 610 days, the time needed for the replacement of many of its heat shield tiles.
Not only was this the first launch of the Space Shuttle, but it marked the first time that solid-fuel rockets were used for a NASA crewed launch (although previous systems had used solid-fuel motors for their escape towers or retro rockets). STS-1 was also the first U.S. crewed space vehicle launched without an uncrewed powered test flight. The STS-1 orbiter, Columbia, also holds the record for the amount of time spent in the Orbiter Processing Facility (OPF) before launch – 610 days, the time needed for the replacement of many of its heat shield tiles.
The NASA mission objective for the maiden flight was to
accomplish a safe ascent into orbit and return to Earth for a safe
landing of Orbiter and crew. The only payload carried on the mission was
a Development Flight Instrumentation (DFI) package, which contained
sensors and measuring devices to record the orbiter's performance and
the stresses that occurred during launch, ascent, orbital flight,
descent and landing. All 113 flight test objectives were accomplished,
and the orbiter's spaceworthiness was verified.
During the final T−9 minute holding period, Launch Director George Page read a message of good wishes to the crew from President Ronald Reagan,
ending with, "John, we can't do more from the launch team than say, we
wish you an awful lot of luck. We are with you one thousand percent and
we are awful proud to have been a part of it. Good luck gentlemen."
Ignition of the three RS-25
main engines was sensed as a sharp increase in noise. The stack rocked
"downwards" (towards the crew's feet), then back up to the vertical, at
which point both Solid Rocket Boosters
(SRBs) ignited. Crippen likened lift-off to a "steam catapult shot"
(such as when an aircraft is launched from an aircraft carrier). The
stack's combined northwards translation and climb above the launch
tower's lightning rod were readily apparent to Young. After clearing the
tower the stack began a right roll (until the +Z axis or vertical fin
pointed) to a launch azimuth of 067° True (in order to achieve an orbital inclination of 40.30°), and pitched to a "heads down" attitude (to reduce loading on the wings). Simultaneously control was passed from the launch team in Florida to Flight Director Neil Hutchinson's Silver team in Flight Control Room 1 (FCR 1) in Texas with astronaut Dan Brandenstein as their CAPCOM.
Columbia's main engines were throttled down to 65% thrust to transit the region of Max Q, the point during ascent when the shuttle undergoes maximum aerodynamic stress. This occurred 56 seconds into the flight at Mach 1.06.[10]
The wind corrected value was 29 kPa (4.2 psi) (predicted 28 kPa
(4.1 psi), limit 30 kPa (4.4 psi)). The two SRBs performed better than
expected causing a lofted trajectory,
and were jettisoned after burnout at 2 minutes and 12 seconds (at
53,000 m (174,000 ft) altitude, 2,800 m (9,200 ft) higher than planned).
After 8 minutes and 34 seconds Mission Elapsed Time
(MET), the main engines were shut down (MECO, at altitude 118,000 m
(387,000 ft)) and the external tank was jettisoned 18 seconds later to
eventually break up and impact in the Indian Ocean. Two twin-engined Orbital Maneuvering System
(OMS) engine burns of 86 seconds duration initiated at 10 minutes and
34 seconds MET and 75 seconds duration at 44 minutes 2 seconds MET
inserted Columbia into a 246 × 248 km (153 × 154 mi) orbit. This subtle deviation from the original plan of 240 km (150 mi) circular went largely unnoticed. In fact, it
adjusted the spacecraft's orbital period to take account of the April
10, 1981, scrub, so that attempts could still be made to use KH-11 reconnaissance satellites to image Columbia on orbit. Overall Young commented that there was a lot less vibration and noise
during launch than they had expected. However, the sensations
accompanying the first firing of the large Reaction Control System
(RCS) jets surprised the crew. Crippen commented "it's like a big
cannon just fired ... you don't like them the first time you hear them".
Young reported that "the entire cabin vibrates ... it felt like the
nose was being bent".
Once on-orbit both crew members safed their ejection seats and
unstrapped. The next critical event was payload bay door opening. This
was essential to allow heat rejection from Columbia's
systems via the doors' space radiators. Failure to open these by the
end of the second orbit would have resulted in a return to Earth at the
end of the fifth orbit, before the limited capacity of the flash
evaporator cooling system was exceeded. As they opened the doors the
crew noticed that they had sustained damage to thermal protection system
(TPS) tiles on the OMS pods. This was televised to the ground. Shortly
afterwards Young, then Crippen doffed their emergency ejection suits.
The majority of the crew's approximately 53 hours in low Earth orbit was spent conducting systems tests. Despite the scheduling impact of efforts to image Columbia's
TPS by utilizing external assets, these were all accomplished. They
included: Crew Optical Alignment Sight (COAS) calibration, star tracker
performance, Inertial Measurement Unit
(IMU) performance, manual and automatic RCS testing, radiation
measurement, propellant crossfeeding, hydraulics functioning, fuel cell
purging, and photography. The OMS-3 and OMS-4 burns at 006:20:46 and
007:05:32 MET respectively raised this orbit to 273.9 × 274.1 km
(170.2 × 170.3 mi) (compared to a planned 280 km (174 mi) circular).
These two firings were single engined utilizing the crossfeed system.[13]
The crew reported a cold first night on board despite acceptable
temperature indications. They found the second night comfortable after
settings were adjusted.
During the second day of the mission, the astronauts received a phone call from Vice President George H. W. Bush. President Ronald Reagan had originally intended to visit the Mission Control Center during the mission, but at the time was still recovering from an assassination attempt which had taken place two weeks before the launch (Reagan had returned home to the White House only the day prior to the launch).
The crew awoke from their second sleep period earlier than
planned. Preparations for return to Earth began with breakfast. Stowing
of cabin items, flight control system checkout, data processing system
reconfigurations, and then ejection suit donning followed. In Houston,
the Crimson team headed by their Flight Director Don Puddy came on duty in FCR 1 for the mission's final shift. His CAPCOM was astronaut Joseph P. Allen with Frederick Hauck
assisting. Payload bay door closing was a critical milestone to ensure
vehicle structural and thermal integrity for re-entry. If power closing
had failed, Crippen was trained to conduct a one-man extravehicular activity
(EVA) to manually winch them closed. With cabin switch positions
verified, the crew strapped into their ejection seats. Meanwhile, Johnson Space Center (JSC) pilots Charlie Hayes and Ted Mendenhall were airborne over California's Edwards Air Force Base area in a Shuttle Training Aircraft (STA) performing a final check of landing weather conditions.
Auxiliary Power Units
(APUs) 2 and 3 were started (to provide flight control hydraulic
pressure). The 160-second twin-engine OMS de-orbit burn took place
during the 36th orbit over the southern Indian Ocean and changed the
orbital parameters from 270 × 274 km (168 × 170 mi) to 270 × 0 km
(168 × 0 mi). This ensured atmospheric capture of the spacecraft close
enough to the planned landing site to have sufficient energy for a
controlled glide landing, but not so close that energy would have to be
dissipated at a rate exceeding its structural capability. Young then
slowly pitched Columbia up to the wings level nose high entry
attitude. Both crew members armed their ejection seats during this pitch
around. Nearly half an hour later APU 1 was started as planned. Shortly
afterwards, Columbia entered an approximately 21-minute long
communications blackout. This was due to a combination of ionization (16
minutes) and lack of ground station coverage between Guam and Buckhorn Tracking Station at Dryden Flight Research Facility. Entry Interface (EI) was reached over the eastern Pacific Ocean
8,110 km (5,040 mi) from the landing site at a speed of around
28,240 km/h (17,550 mph). EI is merely an arbitrarily defined geodetic
altitude of 120,000 m (390,000 ft) employed by NASA for the purposes of
trajectory computations and mission planning. Above this altitude, the
spacecraft is considered to be outside the "sensable atmosphere".
Most of this first orbiter entry was flown automatically. An initial angle of attack
of 40° had to be maintained until through the most severe aerodynamic
heating after which it was gradually reduced. At about 100,000 m
(330,000 ft) altitude a light pink air glow caused by entry heating
became visible, and both crew members lowered their visors. Columbia
had to maneuver 583 km (362 mi) "cross range" of its orbital ground
track to reach the planned landing site during the entry. Consequently, a
roll into a right bank was flown when the air density had increased
sufficiently to raise dynamic pressure to 570 Pa (0.083 psi) (with speed
still in excess of Mach 24
and approximately 78,000 m (256,000 ft) altitude). Automatic roll
reversals to control energy dissipation rate and cross range steering
were performed at around Mach 18.5 and Mach 9.8. The crew clearly observed the coast of California as Columbia
crossed it near Big Sur at Mach 7 and 41,000 m (135,000 ft). Both the
Mach 4.8 and Mach 2.8 roll reversals were automatically initiated and
manually completed by John Young. The last RCS jet firing took place at
an altitude of 17,000 m (56,000 ft) - 4,300 m (14,100 ft) lower than
desired (due to a predicted risk of combustion chamber explosion).
Young again took manual control for the remainder of the flight
as they went subsonic approaching the Heading Alignment Circle (HAC). A
wide left turn was flown to line up with lake bed runway 23, whilst T-38 "Chase 1", crewed by astronauts Jon McBride and "Pinky" Nelson joined formation. Main gear touch down occurred on runway 23 at Edwards Air Force Base, at 339 km/h (211 mph) equivalent airspeed,
slightly slower and around 800 m (2,600 ft) further down the runway
than planned. This was the result of a combination of better than
predicted Orbiter lift-to-drag ratios and tail wind. Touch down time was
18:21 UTC on April 14, 1981. As they rolled to a stop, Young remarked over the radio, "This is the
world's greatest all electric flying machine. I'll tell you that. That
was super!"
Columbia was returned to Kennedy Space Center from California on April 28, 1981, atop the Shuttle Carrier Aircraft. The 36-orbit, 1,729,348 km (1,074,567 mi) flight lasted 2 days, 6 hours, 20 minutes and 53 seconds.
