STS-41-D

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STS-41-D
Mission insignia
Mission statistics
Mission name	STS-41-D
Space shuttle	Discovery
Launch pad	39-A
Launch date	30 August, 1984, 12:41:50 UTC
Landing	5 September, 1984, 15:37:54 UTC Edwards AFB
Mission duration	6d/00:56:04
Number of orbits	97
Orbital altitude	184 nautical miles (341 km)
Orbital inclination	28.5°
Distance traveled	2,490,000 miles (4,010,000 km)
Crew photo
Back row: L-R: Walker, Resnik Front row L-R: Mullane, Hawley, Hartsfield, Coats
Related missions
Previous mission Next mission STS-41-C STS-41-G

STS-41-D was the first space shuttle mission for Space Shuttle Discovery. It was the 12th shuttle mission, and launched from Kennedy Space Center, Florida on 30 August, 1984.

Crew

Mission parameters

• Mass:
  • Orbiter Liftoff: 263,477 pounds (119,511 kg)
  • Orbiter Landing: 201,674 pounds (91,478 kg)
  • Payload: 41,184 pounds (18,681 kg)
• Perigee: 187 nautical miles (346 km)
• Apogee: 191 nautical miles (354 km)
• Inclination: 28.5°
• Period: 90.6 min

Mission highlights

The orbiter Discovery was launched on its maiden flight, the 12th in the program, on 30 August 1984. It was the third orbiter built and the lightest one thus far because of its lightweight thermal blanket material.

The mission was originally planned for 25 June 1984, but because of a variety of technical problems, including rollback to the VAB to replace a main engine, the launch did not take place until 8:41 a.m. EDT, 30 August 1984, after a 6-minute, 50-second delay when a private aircraft flew into the restricted air space near the launch pad. It was the fourth launch attempt for Discovery. The June launch attempt marked the first time since Gemini 6A that a Manned Spacecraft experienced a shutdown of its engines just prior to launch.

The launch of STS-41-D.

Because of the 2-month delay, the STS 41-F mission was cancelled (STS 41-E had already been cancelled) and its primary payloads were included on the STS 41-D flight. The combined cargo weighed over 41,184 pounds (18,681 kg), a Space Shuttle record up to that time.

The six-person flight crew consisted of Henry W. Hartsfield Jr., commander, making his second Shuttle mission; pilot Michael L. Coats; three mission specialists:—Judith A. Resnik, Richard M. Mullane and Steven A. Hawley; and a payload specialist, Charles D. Walker, an employee of the McDonnell Douglas Corp. Walker was the first commercially-sponsored payload specialist to fly aboard the Shuttle.

The primary cargo consisted of three communications satellites, SBS-D for Satellite Business Systems, Telstar 3-C for Telesat of Canada and SYNCOM IV-2, or Leasat-2, a Hughes-built satellite leased to the Navy. Leasat-2 was the first large communications satellite designed specifically to be deployed from the Space Shuttle. All three satellites were deployed successfully and became operational.

Another payload was the OAST-l solar array, a device 13 feet (4.0 m) wide, and 102 feet (31 m) high, which folded into a package 7 inches (180 mm) deep. The wing carried a number of different types of experimental solar cells and was extended to its full height several times. It was the largest structure ever extended from a manned spacecraft and demonstrated the feasibility of large lightweight solar arrays for future application to large facilities in space such as the Space Station.

The McDonnell Douglas-sponsored Continuous Flow Electrophoresis System (CFES) experiment, using living cells, was more elaborate than the one flown previously and payload specialist Walker operated it for more than 100 hours during the flight. A student experiment to study crystal growth in microgravity was carried out. Highlights of the mission were filmed using an IMAX motion picture camera, and these later appeared in The Dream is Alive.

The mission lasted 6 days, 56 minutes, with landing on Runway 17 at Edwards AFB, at 8:37 a.m. PDT, on 5 September 1984. It traveled 2,490,000 miles (4,010,000 km) and made 97 orbits. It was transported back to KSC on 10 September 1984.

26 June launch attempt

During the 26 June 1984 launch attempt of STS-41-D there was a launch abort at T-4 seconds followed by a pad fire around ten minutes later. ^{[1] [2]}

Commentary: "We have a cut off."
"NTD we have a RSLS (Redundant Sequence Launch Sequencer) abort."
Commentary: "We have an abort by the onboard computers of the orbiter Discovery."
"Break Break, Break Break, DLS shows engine one not shut down."
"OK, PLT?"
"CSME verify engine one."
"You want me to shut down engine one?"
"We do not show engine start on one."
"OTC I can verify shutdown on verify on engine one, we haven't start prepped engine one."
"All engines shut down I can verify that."
Commentary: "We can now verify all three engines have been shut down."
"We have red lights on engines two and three in the cockpit, not on one."
"All right, CSME verify engine one safe for APU shutdown."
"If I can verify that?"
"OTC GPC go for APU shutdown."
^[3] (Audio from CNN, transcript starting at 9:48)

Steve Hawley, one of the crew, broke the tense atmosphere following the abort in the shuttle cabin saying: "Gee, I thought we'd be a lot higher at MECO (Main Engine Cut-Off)!".^[4]

About ten minutes later the following was heard on the live TV coverage (at 22:45 of the audio file referenced above):

"We have indication two of our fire detectors on the zero level; no response. They're side by side right next to the engine area. The engineer requested that we turn on the heat shield firewall screen between the engine valve and Discovery's three main engines."

While evacuating from the shuttle, the crew was doused with water from the pad deluge system, which was activated due to a hydrogen fire on the launch pad. ^[5]

Changes to procedures resulting from this abort included more practicing of "safeing" the orbiter following aborts at various points, the use of the fire suppression system in all pad aborts, and the testing of the slidewire escape system with a real person (Charles F. Bolden, Jr.). It emerged that launch controllers were reluctant to order the crew to evacuate as the slidewire had not been ridden by a human. ^[4]

Wake-up calls

A tradition for NASA human spaceflights since the days of Gemini, mission crews are played a special musical track at the start of each day in space. Each track is specially chosen, often by their families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities. ^[6]

Gallery

SBS-D after deployment

Syncom IV-2 after deployment

Telstar 3-C after deployment

OAST-1 solar array

Mission insignia

The twelve stars of the mission insignia symbolize the flight's numerical designation in the Space Transportation System's mission sequence.

References

See also

• Space science
• Space Shuttle
• List of space shuttle missions
• List of human spaceflights chronologically

External links

• NASA mission summary
• STS-41D Video Highlights
• The Dream is Alive IMAX film with footage from STS-41-D