NASA Johnson Space Center’s Shuttle II (1988) - For NASA Nerds Only

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NASA Johnson Space Center’s Shuttle II (1988)


A year ago today, the Space Shuttle Orbiter Atlantis was docked with the International Space Station (ISS). On 21 July 2011, it deorbited and landed back on Earth, ending 30 years of Space Shuttle flights. The decision to end the Shuttle Program after ISS completion was taken by President George W. Bush in 2004. The Space Shuttle’s successor, the Orion capsule, was not ready when Atlantis returned to Earth. Fortunately, the 20-year cooperative relationship with the Russian space program ensured that American astronauts could continue to live and work on board the ISS.

Although the fact is mostly forgotten today, NASA launched plans to replace the Space Shuttle even before the first Space Shuttle mission in April 1981. In 1985, President Ronald Reagan formalized these by signing a directive ordering the U.S. civilian space agency to develop a Space Shuttle successor. Notably, this occurred before the January 1986 Challenger accident laid bare the Space Shuttle’s frailties. NASA has attempted to develop a Space Shuttle successor ever since, but for a wide range of reasons it has not succeeded.

One of the early proposed Shuttle successors was called Shuttle II. The lion’s-share of Shuttle II design work took place at NASA’s Langley Research Center (LaRC) in Hampton, Virginia. Shuttle II first achieved prominence in 1986 in the high-level National Commission On Space report. LaRC’s Shuttle II design evolved – for a time it was to have been a single-stage-to-orbit vehicle – although typically it included a winged manned Orbiter and a winged unmanned Booster, both of which would have landed on runways and been entirely reusable. The Shuttle II Orbiter’s fuselage would have been crammed full of propellant tanks, so it would have toted cargo in a sizable hump on its back.

Shuttle II was intended mainly as a crew transport complementing a “mixed fleet” of launchers that would have included unmanned heavy-lift rockets capable of placing from 50 to 100 tons into space. It would have transported a small amount of cargo – perhaps 10 tons – and a large number of astronauts – between 10 and as many as 25 – to an established, mature Space Station. Only a handful of astronauts – perhaps three – would have been Shuttle II crewmembers; the remainder would have been considered passengers. Upon reaching space on board Shuttle II, they would have either served aboard the Space Station or transferred to spacecraft bound for the moon or Mars.




Although a good case can be made for calling LaRC’s Shuttle II the Shuttle II, it was in fact not the only proposed Shuttle II design. The Advanced Programs Office at NASA Johnson Space Center (JSC) in Houston, Texas, put forward the sleek Shuttle II design depicted in the images that follow. The LaRC design was favored by NASA Headquarters and is relatively well documented. Neither can be said for JSC’s design. These images – NASA photos of a model – constitute a rare glimpse at a spaceship that never was.

Engineers in Houston envisioned that their Shuttle II might develop from an Evolved Space Shuttle. In the Evolved Shuttle, Liquid Replacement Boosters would have stood in for the Space Shuttle’s Solid Rocket Boosters, though the Evolved Shuttle would have retained the Space Shuttle’s expendable External Tank and, with minor modifications, the Space Shuttle Main Engines (SSMEs). Winglets on the tips of the Evolved Shuttle’s modified delta wings would have replaced the Space Shuttle’s single vertical tail fin. Redesigned Orbital Maneuvering System (OMS) engines based on the venerable RL-10 engine would have drawn liquid hydrogen/liquid oxygen propellants from tanks in the wings.



The most dramatic change, however, was reserved for the crew compartment. It would have been completely redesigned so that it could separate from the rest of the Evolved Shuttle in the event of a catastrophic failure and operate as an independent small piloted spacecraft. This feature, along with the wing configuration, would carry over to JSC’s Shuttle II design.

NASA JSC engineers gave no indication of when they expected the transition from Space Shuttle to Evolved Shuttle would occur. If one assumes, however, that JSC’s Shuttle II would have become operational in the first years of the 21st century – like LaRC’s Shuttle II – then the Evolved Shuttle would probably have flown during the 1990s.

Emergency Escape

Unlike the Space Shuttle, which even after Challenger included few realistic options for crew escape in the event of catastrophic failure, Shuttle II could in theory have protected its crew through all phases of its mission. Like the Evolved Shuttle, Shuttle II would have included forward canard wings to enhance stability during atmospheric flight; following separation, these would have become the crew compartment’s wings. The crew compartment’s aft end would have included launch escape and deorbit rocket engines, a crew hatch, and a deployable aerodynamic flap. Following separation in orbit, the crew compartment could have supported 11 astronauts for up to 24 hours. This endurance was designed to ensure that Earth’s rotation would bring into range a suitable landing site on U.S. soil. The crew compartment would have touched down and slid to a halt on extendable skids.

JSC engineers acknowledged that wind-tunnel testing might show that the Shuttle II crew compartment shape was not flight-worthy in all abort situations. They proposed that extendable or inflatable structures “be employed to obtain an acceptable configuration for hypersonic, supersonic, and subsonic controlled flight.”

They also proposed that the Shuttle II crew compartment become the Space Station’s Crew Emergency Rescue Vehicle (CERV). The CERV was conceived as a “lifeboat” for use if the Space Station had to be evacuated rapidly (for example, in the event of fire), if a crew member became seriously ill or injured and needed hospital treatment on Earth, or if Shuttle II became grounded due to malfunction or accident and could not retrieve a Space Station crew.

The JSC engineers noted that the Shuttle II crew compartment/CERV, like Shuttle II itself, would subject its occupants to no more than three gravities of acceleration or deceleration. This would have helped to ensure that, during return to Earth, it would not inflict additional harm on a sick or injured Space Station crewmember.