{"id":24795,"date":"2021-11-12T17:37:54","date_gmt":"2021-11-12T09:37:54","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/40-years-after-sts-2-columbias-second-flight-and-the-path-to-reusability\/"},"modified":"2021-11-12T17:37:54","modified_gmt":"2021-11-12T09:37:54","slug":"40-years-after-sts-2-columbias-second-flight-and-the-path-to-reusability","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/40-years-after-sts-2-columbias-second-flight-and-the-path-to-reusability\/","title":{"rendered":"40 years after STS-2: Columbia\u2019s second flight and the path to reusability"},"content":{"rendered":"

April 14, 1981. The orbiter Columbia rested on a runway at Edwards Air Force Base, California, having completed the first-ever Space Shuttle mission. Now a daunting task lay ahead. Something that had never been attempted before would now have to become reality.<\/p>\n

Columbia would have to be turned around for a second mission. No longer would a U.S. crewed spacecraft be used only once.<\/p>\n<\/p>\n

Ferried back across the country, Columbia arrived at the Kennedy Space Center on April 28, where teams removed her from the back of the Shuttle Carrier Aircraft, a heavily modified Boeing 747, and returned her to the Orbiter Processing Facility (OPF) for turnaround operations \u2014 much of which involved detailed inspections as well as repairs to several of her systems that were damaged during STS-1.<\/p>\n

Most notable of these were the damage imparted to the body flap during the overpressure event at Solid Rocket Booster (SRB) ignition and the Thermal Protection System (TPS) tile damage.<\/p>\n

After studying the SRB overpressure issue after Columbia\u2019s first liftoff, NASA increased the sound suppression system for STS-2 to deaden the sound as much as possible given the lesson learned with STS-1 \u2014 efforts that ultimately proved successful.<\/p>\n

For the tiles, more than 1,300 TPS tiles had to be replaced in the OFP during the turnaround flow for STS-2.<\/p>\n

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Columbia\u2019s replaced TPS tiles ahead of STS-2. Via L2 Historical<\/p>\n

Also changing with STS-2 was the countdown for the Space Shuttle program, which for the first mission saw auto-sequence start and handoff to Columbia\u2019s onboard computers at the T-27 second mark, with main engine ignition at T-3.3 seconds and liftoff at T+3.3 seconds \u2014 at which point the Mission Elapsed Timer reverted to zero.<\/p>\n

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To streamline this, the countdown was adjusted so that auto-sequence start would occur at T-31 seconds, with main engine ignition at T-6.6 seconds and liftoff at T0. This sequence would remain in place until the end of the program.<\/p>\n

Also tweaked from a ground support equipment side for STS-2 was the retraction time of the gaseous oxygen vent arm, which during STS-1 was removed during the T-9 minute hold. For STS-2 onward, the retraction sequence would initiate at T-2 minutes 55 seconds, the same time the liquid oxygen tank of the External Tank began pressurization for flight.<\/p>\n

Aside from Columbia herself, the External Tank for STS-2 arrived at the Kennedy Space Center on April 22, 1981, where it was lifted into a check-out cell in one of the High Bays of the Vehicle Assembly Building (VAB) for post-shipment inspections and pre-mate configurations.<\/p>\n

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STS-2\u2019s White External Tank in the VAB, via NASA<\/p>\n

By early June, assembly of the twin Solid Rocket Boosters was complete inside the VAB, and the External Tank was mated to the SRBs on June 30.<\/p>\n

Inside the Orbiter Processing Facility, technicians installed the Spacelab pallet with the five experiments of the OSTA-1 (Office of Space and Terrestrial Applications-1) payload into Columbia\u2019s payload bay during June. It was also during this month that Columbia became the first orbiter to receive her Canadian-built remote manipulator system (RMS \u2014 more colloquially known as Canadarm).<\/p>\n

The RMS was installed in Columbia on June 29.<\/p>\n

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The installation of the RMS on Columbia for STS-2, via L2 Historical<\/p>\n

By July 29, engineers and technicians inside the OPF completed an intensive, two-day orbiter integrated test that verified that Columbia\u2019s hardware and software were once again ready for a flight.<\/p>\n

By this time, the launch of Columbia on STS-2 was targeted for September 30, with a planned mission duration of five days six hours. \u201cWe\u2019re going to be ready when the bird\u2019s ready,\u201d said STS-2 commander Joe Engle in an August 3 pre-flight press conference.<\/p>\n

\u201cOur mission rules are very conservative. If we have a failure and our mission rules cause us to come home early, we will do that. I would still call it a successful flight,\u201d he added \u2014 words that would ultimately prove prophetic.<\/p>\n

On August 10, after 99 days in the OPF, Columbia rolled to the VAB for mating to her External Tank. Unlike the latter half of the program where the orbiters were moved on a dedicated transporter called the Orbiter Transport System (OTS), Columbia was towed to the VAB on her landing gear.<\/p>\n

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STS-2 Rollover to the VAB, via NASA<\/p>\n

Once in the transfer aisle, Columbia was attached to the hoisting\/mating sling \u2014 itself attached to two overhead cranes, and then lifted slightly off the ground at which point teams retracted her landing gear for flight.<\/p>\n

Columbia was then raised vertically. At this point, the aft attach sling was removed before Columbia was rolled 45\u00b0 and then lifted up and over the transom and into the High Bay for connection to her External Tank.<\/p>\n

After electrical connections were made, engineers undertook a 9-day Shuttle Interface Test, which verified all of the mechanical and electrical connections between the stack as well as the functionality of Columbia\u2019s flight systems.<\/p>\n

Concurrently, the prime and backup crews conducted simulated countdowns and launches that used two launch profiles \u2013 the normal one that could be expected as well as Return To launch Site abort profile. Entry and landing simulations were also undertaken.<\/p>\n

However, the effort of turning around a crewed spacecraft for the first time for a second flight in space was, as expected, causing certain events to take longer than planned. As a result, NASA managers slipped Columbia\u2019s second launch to October 2 on August 26.<\/p>\n

Just before 5 AM local time on August 31, technicians began rolling Columbia out to pad 39A. The entire journey took just more than seven hours to complete. At this time, a countdown demonstration test was scheduled for mid-September and the launch was once again moved to October 9.<\/p>\n

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STS-2 Columbia rolls to the launch pad, via L2 Historical<\/p>\n

The STS-2 backup crew of Ken Mattingly and Henry Hartsfield undertook emergency egress training where they learned how to use the slide wire escape system as well as how to drive the armored personnel carrier if they would need to evacuate the launch pad.<\/p>\n

The countdown demonstration test successfully took place on September 9 with a simulated countdown that saw the prime crew of Engle and Truly walkthrough launch day procedures with the team, including testing of their launch pressure suits as well as entry into Columbia and simulated main engine ignition.<\/p>\n

This general practice would evolve throughout the program to become known as the terminal countdown demonstration test.<\/p>\n

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Joe Engle and Richard Truly ahead of STS-2, via NASA<\/p>\n

Following the countdown practice with the crew, a fueling test of Columbia occurred on September 15 to continue gathering data on how the External Tank\u2019s spray-on foam insulation reacted to the cryogenic fueling process and to test improvements to the foam following STS-1.<\/p>\n

With a successful series of tests behind her, Columbia was looking good for a launch in mid-October\u2026 until three gallons of highly corrosive hypergolic nitrogen tetroxide oxidizer was spilled over the orbiter\u2019s starboard side during fueling of the Forward Reaction Control System on September 22.<\/p>\n

The oxidizer made its way between numerous TPS tiles on the forward portion of the vehicle, and subsequent inspections revealed that the nitrogen tetroxide had melted the glue that held the tiles in place, resulting in the need to re-apply roughly 370 tiles \u2013 many of which fell off on their own after their adhesive melted.<\/p>\n

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Columbia on 39A ahead of STS-2, via L2 Historical<\/p>\n

The time-consuming nature of the work resulted in a further slip of the mission to November 4.<\/p>\n

Countdown preparations began on October 23, with the count itself commencing on October 31 for a planned 7:30 am EST launch on November 4. Engle and Truly flew to the space center on November 2 for launch.<\/p>\n

The count proceeded relatively smoothly, with Columbia fully fueled in the early morning hours. Engle and Truly suited up and boarded Columbia with all \u2014 expect marginal weather \u2014 looking good for liftoff.<\/p>\n

Until the T-9 minute hold.<\/p>\n

During this time, launch personnel noticed indications of lower than acceptable pressures within the oxygen tank of the External Tank. While working on the issue, the hold at T-9 minutes was extended even though engineers were able to quickly resolve the issue.<\/p>\n

Countdown then resumed before halting at the T-31 second mark when the ground launch sequencer (GLS) refused to hand over control of the count to Columbia\u2019s onboard flight computers, initiating a hold in the terminal sequence.<\/p>\n

The issue was traced to Auxiliary Power Units (APUs) 1 and 2, which showed lube oil outlet pressures of 100 and 112 psi.<\/p>\n

Facing uncertain technical issues as well as deteriorating weather, the launch attempt was scrubbed and the launch was reset for November 12 to allow teams time to properly understand the issues that had presented during the final moments of the count.<\/p>\n

Unfortunately for Columbia, the fuel cell issue a T-31 seconds would be yet another prophetic moment.<\/p>\n

On November 12, the launch was delayed two hours 40 minutes after one of Columbia\u2019s Multiplexer-Demultiplexer units failed and a replacement was rushed across the country from Challenger, still under construction in California.<\/p>\n

An additional 10-minute delay occurred as launch teams met to review confidence in systems status for liftoff.<\/p>\n

On November 12 at 10:10 AM EST, coincidentally seven months to the day after she launched on STS-1 and 214 days after she returned from her first mission, Columbia took the skies over Florida once more and became the first crewed spacecraft to make a return journey to space.<\/p>\n<\/p>\n