Workhorse for the New Age: The Space Shuttle

The world's first reusable spacecraft

Wanted: Dead or Alive by Bon Jovi

Space Shuttle Atlantis (OV-104) departs on STS-45 on March 24, 1992. The mission featured a crew of seven (Commander Charles F. Bolden, Pilot Brian Duffy, Payload Commander Kathryn D. Sullivan, Mission Specialists David C. Leestma and C. Michael Foale, and Payload Specialists Byron K. Lichtenberg and Dirk D. Frimout) and the Atmospheric Laboratory for Applications and Science-1 (ATLAS-1) payload. NASA Photo.

A reusable spacecraft had been one of the goals of the American manned space program since the early 1950s, when the X-15 was in the conceptual phase. When the Soviets orbited Sputnik 1 in October of 1957, a sort of war-effort mentality took over in Washington DC and much of the aerospace community; the public was demanding a quick and easy way of getting Americans into space. The Air Force, NACA, and the Navy had been planning a gradual development of the X-15 into a two-seat, orbital X-15B, and then later, a more advanced winged spaceplane called the Boeing X-20 DynamicSoaring vehicle, also known as the DynaSoar. These vehicles would be launched either from a B-52 mothership, or later, from a Titan I (later Titan III) launch vehicle, orbit the earth, and land on a runway or dry lakebed like rocket planes had been doing for over a decade. Then they could be "turned around" and used again.

Sputnik changed all that. The X-15B and X-20 were years away; they needed men up there as soon as possible. So the expendable "space capsule" approach was used; use a modified ICBM to lob a guy into space in a disposable tin can with instrumentation, rudimentary reaction controls, and a parachute. (As the von Braun character in the film version of The Right Stuff said, "It would go up like a cannonball! And come down....like a connonball!") Which would get American pilots into space quick and easy, but you could never use the launch vehicle or spacecraft again. What launched the mission would be junk, and what came back would be a museum piece.

But the capsule concept worked well enough, and all through the 1960s and 1970s, NASA stuck with the expendable spacecraft. Astronauts orbited the earth in Mercury capsules, learned the spaceflight game in Gemini capsules, flew to the Moon and Skylab and rendezvoused with the Russians in Apollo capsules. But the supply of capsules would be hard to sustain unless the country really committed to some sort of mass-production program, and that just wasn't fiscally or politically feasible. The reusable spaceplane concept re-emerged in the late 1960s. The Nixon administration was enthusiastic about the concept, and the new vehicle, known as the Space Shuttle, was approved in April of 1972. When it was given the green light, John Young and Charlie Duke were on the surface of the Moon, exploring the Descartes Region on Apollo 16.

At first, the whole system was supposed to be reusable. The Shuttle was to have been launched aboard a high-flying, reusable, hypersonic mothership of some sort, but this was rejected. NASA looked at launching the Shuttle on a highly-modified Saturn V, but this too was rejected. Finally, a semi-reusable launch system was developed. It had 4 parts: the Shuttle Orbiter (the spaceplane itself), a large expendable External Tank (ET) to fuel the Orbiter's main engines, and two reusable Solid Rocket Boosters (SRBs) strapped to the sides of the tank, which would provide thrust from liftoff to just after 2 minutes into the mission. At that point, the SRBs would be jettisoned, and the Orbiter would burn fuel and oxidizer from the ET until just before it reached orbit. Then, the tank would be jettisoned, and the Orbiter would use its Orbital Maneuvering System (OMS) engines to establish itself in orbit. The tank would burn up somewhere over the Indian Ocean-the only component that couldn't be reused. The SRBs would parachute into the ocean for retrieval, refurbishment and reuse, and the Orbiter would land on a runway and be turned around like some sort of really finicky, expensive airliner. The whole setup was known as the Shuttle Transportation System, or STS.

Video: The launch of STS-70/Discovery, 7/13/95 (M)

This 30-second video shows the launch of a typical Shuttle mission. It starts with Discovery just before liftoff, thru Main Engine start, SRB ignition, and thru the roll and pitch programs during ascent. Note the jets of sparks beneath the main engines just before ignition; these are known as the Space Shuttle Main Engine Hydrogen Burnoff System. These "pre-burners" are used to burn off any "free" hydrogen in the area of the SSMEs before ignition, to prevent the buildup of explosive gasses.

Video: Launch from camera on External Tank (R)

Video: Shuttle launch w/SRB separation (M)

This video shows an edited version of the launch thru SRB sep. Note the clouds of condensation that form around the vehicle as it ascends

Video: SRB sep-from the SRB point of view (M)

Video: External Tank sep-slow motion (M)

The last Shuttle Orbiter built, Endeavour (OV-105), is carried out to Pad 39A in preparation for STS-111/UF-2 (a flight to the International Space Station) in April, 2002. Visible here are many of the new facilities and leftover Apollo-era hardware used to launch the Shuttle. The spacecraft stack rests on a modified Saturn V Mobile Launcher Platform (MLP), which is carried out from the VAB by one of the Crawlers (the tank tracks of which are visible on the trackways at lower right). To the left of the stack is the modified Saturn V Launch Umbilicle Tower (LUT) that has been removed from an MLP, chopped in half, fixed in place, and modified for Shuttle operations; this structure is now known as a Fixed Service Structure or FSS. And the big structure attached to that is the Rotating Service Structure (RSS), which swings over to cover the vehicle during preparations. NASA Photo.

Video: STS-92 approach/landing at Edwards AFB (R)

Video: Shuttle landing at the Cape (R)

This clip shows STS-112/Atlantis landing at the Shuttle Landing Facility at Kennedy Space Center, complete with Heads-Up Display (HUD) info, final approach over the swamps, and a touchdown with braking chute. The jet noise heard in these clips is from the T-38 and Gulfstream-II STA (Shuttle Training Aircraft) chase planes.

Video: STS-104 KSC night landing (R)

Although much of the flying hardware was new, NASA's ground-based assets would make use of as much off-the-shelf Apollo technology as possible. The handling equipment in the VAB was modified for Shuttle operations. The Mobile Launcher Platforms (MLPs) used for Saturn launches were modified to accept the STS stack. The Crawlers still hauled the MLPs and vehicles around. The two Saturn V launch pads at Launch Complex 39 were modified. Two of the collossal Launch Umbilicle Towers (LUTs) were removed from thier MLPs and cut roughly in half (the Shuttle stack is just over 184 feet tall, compared to the 363-foot Saturn Vs the LUTs were designed for), and the top half of the structure-containing the White Room, some access arms, and the lightning rod-was fixed permanently in place next to the pads. This was now called the Fixed Service Structure or FSS. Hinged onto that was a new structure known as the Rotating Service Structure (RSS) which would be swung into place across the vehicle, allowing technicians acces both to the vehicle and to the payload for final preparations in the weeks leading up to launch.

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