STS-41-D (formerly STS-14) was the 12th flight of NASA's Space Shuttle program, and the first mission of Space Shuttle Discovery.
It was launched from Kennedy Space Center, Florida, on 30 August 1984, and landed at Edwards Air Force Base, California, on 5 September.
Three commercial communications satellites were deployed into orbit during the six-day mission, and a number of scientific experiments were conducted, including a prototype extendable solar array that would eventually form the basis of the main solar arrays on the International Space Station.
The mission was delayed by more than two months from its original planned launch date, having experienced the Space Shuttle program's first launch abort at T-6 seconds on 26 June 1984.
Crew
Crew seat assignments
Mission background
The launch was originally planned for 25 June 1984, but because of a variety of technical problems, including rollback to the Vehicle Assembly Building to replace a faulty main engine, the launch was delayed by over two months.
The 26 June launch attempt marked the first time since Gemini 6A that a crewed spacecraft had experienced a shutdown of its engines just prior to launch.
June launch attempt
During the 26 June launch attempt, there was a launch abort at T-6 seconds, followed by a pad fire about ten minutes later."
Risk of Space Flight"  (PDF).
Wyle Laboratories.
Retrieved 21 June 2013.
Because the center engine had not started when the abort was triggered, confusion ensued as the flight controllers were unable to verify its state:
Commentary: "We have a cut off."
"NTD we have a RSLS (Redundant Set Launch Sequencer) abort."
Commentary: "We have an abort by the onboard computers of the orbiter Discovery."
"Break break, break break, GLS 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."
"STS-41D pad abort".
YouTube.
6 August 2009.
Retrieved 30 April 2012.
Mission Specialist Steve Hawley was reported as saying following the abort: "Gee, I thought we'd be a lot higher at MECO (Main Engine Cut-Off)!"."
Roundup" (PDF).
NASA.
June 2007.
Retrieved 21 June 2013.
About ten minutes later, the following was heard on live TV coverage:
"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 fire water which is what could be seen spraying up in the vicinity of the engine bells of Discovery's three main engines."
"Discovery STS-41-D Mission - Launch - Abort".
YouTube.
12 April 2017.
Retrieved 20 June 2019.
While evacuating 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 caused by the free hydrogen (fuel) that had collected around the engine nozzles following the shutdown and engine anomaly."
Photo of the week 19 (8 August)".
CollectSpace.
Retrieved 21 July 2013.
Because the fire was invisible to humans, had the astronauts used the normal emergency escape procedure across the service arm to the slidewire escape baskets, they would have run into the fire.
Changes to procedures resulting from the abort included more practicing of "safing" 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 during the STS-41-D abort, as the slidewire had not been ridden by a human.
Examination of telemetry data indicated that the engine malfunction had been caused by a stuck valve that prevented proper flow of LOX into the combustion chamber.
Mission summary
STS-41-D launched on 8:41 a.m.
EDT on 30 August after a six-minute, 50-second delay when a private aircraft flew into the restricted airspace near the launch pad.
It was the fourth launch attempt for Discovery.
Because of the two-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 , a record for a Space Shuttle payload 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 McDonnell Douglas.
Walker was the first commercially sponsored payload specialist to fly aboard the Space Shuttle.
Resnik became the second American woman to fly any NASA space mission, after Sally K. Ride.
Primary cargo of Discovery consisted of three commercial communications satellites: SBS-D for Satellite Business Systems, Telstar 302 for Telesat of Canada, and Syncom IV-2, or Leasat-2, a Hughes-built satellite leased to the US 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-1 solar array, a device  wide and  high, which folded into a package  deep.
The array carried a number of different types of experimental solar cells and was extended to its full height several times during the mission.
At the time, it was the largest structure ever extended from a crewed spacecraft, and it demonstrated the feasibility of large lightweight solar arrays for use on future orbital installations, such as the International Space Station.
The McDonnell Douglas-sponsored Continuous Flow Electrophoresis System (CFES) experiment, using living cells, was more elaborate than the one flown on previous missions, and payload specialist Walker operated it for more than 100 hours during the flight.
A student experiment to study crystal growth in microgravity was also carried out.
The highlights of the mission were filmed using an IMAX motion picture camera, and later appeared in the 1985 documentary film The Dream is Alive.
Because of an obstruction in the shuttle's external wastewater dumping system, a two-foot "pee-sicle" formed during the mission; Hartsfield removed it with the Remote Manipulator System.
On 3 September, concern arose over the formation of ice on the waste dump nozzle of the shuttle.
The next day, Hartsfield used the shuttle’s robotic arm to dislodge the large chunk of ice.35 Years Ago: STS-41D – First Flight of Space Shuttle Discovery
The mission lasted 6 days, 00 hours, 56 minutes, 04 seconds, with landing taking place on Runway 17 at Edwards Air Force Base at 6:37 a.m.
PDT on 5 September 1984.
During STS-41-D, Discovery traveled a total of  and made 97 orbits.
The orbiter was transported back to KSC on 10 September 1984.
Ominously, STS-41-D was the first Shuttle mission in which blow-by damage to the SRB O-rings was discovered, with a small amount of soot found beyond the primary O-ring.
Following the Challenger tragedy, Morton Thiokol engineer Brian Russell called this finding the first "big red flag" on SRB Joint and O-ring safety.
Launch attempts
Mission insignia
The 12 stars within the blue field indicate the flight's original numerical designation as STS-12 in the Space Transportation System's mission sequence.
A representation of Discovery's namesake is manifested in a sailing ship, which is linked to the Shuttle (with the OAST solar array in the payload bay) via a red, white, and blue path, signifying its maiden voyage.
Wake-up calls
NASA began a tradition of playing music to astronauts during the Gemini program, and first used music to wake up a flight crew during Apollo 15.
Each track is specially chosen, often by the astronauts' families, and usually has a special meaning to an individual member of the crew, or is applicable to their daily activities.
Gallery
Image:STS41D-36-034.jpg|SBS-D deployment Image:STS41D-36-111.jpg|Syncom IV-2 deployment Image:STS41D-37-050.jpg|Telstar 3C deployment Image:STS41D-01-021.jpg|The extended OAST-1 solar array See also
List of human spaceflights
List of Space Shuttle missions
References
External links
STS-41-D mission summary.
NASA.
STS-41-D National Space Transportation Systems Program Mission Report (PDF).
NASA.
STS-41-D video highlights.
NSS.
The Dream is Alive (1985).
IMDb.
https://www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-41B.html
