![]() By now, launch was targeted for no sooner than 29 September, with a 2.5-hour “window” extending from 9:59 a.m. On 10 August, the three main engines were test-fired satisfactorily and the giant TDRS payload was later installed aboard Discovery. Shortly before rollout, a tiny leak, deep inside the shuttle’s left-side Orbital Maneuvering System (OMS) pod was discovered, but was repaired on the pad. Yet NASA intended to afford STS-26 all the caution which had accompanied STS-1, the first shuttle flight, and Discovery did not finally roll out to Pad 39B at the Kennedy Space Center (KSC) in Florida until 4 July 1988. Bridges resigned from NASA, to return to the Air Force, and was replaced by Covey, whilst Nelson was recalled from an academic post to round out the crew at five. Hauck, Lounge and Hilmers had been training with fellow astronaut Roy Bridges to deploy the Ulysses solar probe on Mission 61F at the time of the Challenger disaster. When the STS-26 crew of Hauck, Covey, Lounge and Mission Specialists Dave Hilmers and George “Pinky” Nelson were named, amid much fanfare, in January 1987, it was hoped that they might launch as soon as February 1988. By this time, T-0 had already been delayed at least one hour into the 2.5-hour “window”, due to unacceptable upper-level wind conditions. “Well, if we’re going to do that,” reasoned Covey, “why don’t we have orange suits?” Looking like “real astronauts” again, in their partial-pressure suits, the STS-26 crew departs the Operations & Checkout (O&C) Building, just before 8 a.m. “As they developed this idea of bailout,” reflected STS-26 Pilot Dick Covey, “the first suits they got were dark blue and the life rafts were black or dark blue.” Should the crew abort and ditch in the ocean, they would never be seen. That said, the STS-26 astronauts at least provided some input into the color of the suits. In the words of STS-26 Mission Specialist Mike Lounge, however, the suits were “political eyewash” and he bemoaned them as adding weight, subtracting payload-carrying capability and serving no useful purpose in the event of a major in-flight emergency. ![]() A new escape system, for use under controlled flight conditions, was added, and future astronauts would wear partial-pressure suits, evolvable into fully-pressurized garments from 1994 onwards. The Space Shuttle Main Engines (SSMEs)-problems with which had triggered a pair of on-the-pad launch aborts and a high-altitude abort situation in the months before 51L-saw attention, as did the orbiter’s brakes and tires. Photo Credit: NASA, via Joachim Becker/Īlthough the boosters had been the “smoking gun” in Challenger’s demise, the 32 months were also spent tending to other issues with the shuttle itself, some considered more useful than others. It was crew input which, in part, led to the transition to orange-colored suits for flight. Clad in blue training versions of their partial-pressure suits, STS-26 astronauts (from left) Dick Covey, Mike Lounge and Dave Hilmers confer in the shuttle simulator. By early 1988, the process of recertifying the entire system for return to flight got underway. In tandem, engineering tests in May 1987 validated SRB heaters, the performance of an additional, third O-ring and the capability of external graphite composite stiffeners to prevent the joints from rotating in flight. ![]() In the months after Challenger, the SRBs were extensively redesigned by their contractor, Morton Thiokol, with a pair of full-scale, short-duration booster simulators-the Joint Environment Simulator and the Nozzle Joint Environment Simulator-used on multiple occasions between August 1986 and August 1988 to test, respectively, new field-joints, insulations and improved O-rings and the physical integrity of the joints between the nozzle and the main motor casing. ![]() As outlined previously by AmericaSpace, the presidential inquiry into the loss of Challenger uncovered a string of cultural and managerial shortcomings, in addition to the root technical cause of the disaster, a cold-induced failure of O-ring seals within one of the twin Solid Rocket Boosters (SRBs). Yet fundamentally, in the words of STS-26 Commander Rick Hauck, the main purpose of the mission “was simply to fly again”, after almost two years of introspection and public and political anger and uncertainty over the avoidable accident that Mission 51L had been. STS-26, the 26th mission of the shuttle program and seventh for frequent-flying Discovery, would deploy a large NASA Tracking and Data Relay Satellite (TDRS) into orbit to permit communications between future astronaut crews and ground stations, as well as relaying data from major scientific spacecraft, including the Hubble Space Telescope (HST). ![]()
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