Saturn-Shuttle

Infobox rocket


caption = Saturn-Shuttle configuration
name = Saturn-Shuttle
country-origin = United States
function = Manned LEO launch vehicle
manufacturer = Boeing (S-IC)
Martin Marietta (External Tank)
Rockwell International (Space Shuttle Orbiter)
height = 85 m
alt-height = 281 ft
diameter = 10 m
alt-diameter = 33 ft
mass = 2,304,000 kg
alt-mass = 5,070,000 lb
stages = 2
LEO-payload = max 60,500 kg
alt-LEO =
status = Cancelled
sites = LC-39, Kennedy Space Center
stage1name = S-IC
stage1engines = 5 Rocketdyne F-1 or F-1A
stage1thrust = max 34.02 MN
alt-stage1thrust = max 7,648,000 lb_f
stage1time = 212 seconds
stage1fuel = RP-1/LOX
stage2name = Shuttle Orbiter & External Tank
stage2engines = 3 Rocketdyne SSMEs
stage2thrust = 6,834.3 kN
alt-stage2thrust = 1,536,312 lb_f
stage2time = ~475 seconds
stage2fuel = LH2/LOX

The Saturn-Shuttle was a proposed interface of the Space Shuttle orbiter and external tank with the S-IC stage on the Saturn V rocket. An interstage would be fitted on top of the S-IC stage to support the external tank, formerly occupied by the S-II stage, so that NASA would have been able to steer completely away from solid rockets. The addition of wings on the S-IC stage would allow the booster to fly back to the Kennedy Space Center in which the technicians would then refurbish the booster (by replacing only the five F-1 engines and reusing the tanks and other hardware for later flights.

Performance

Because the Shuttle orbiter would be riding piggyback on the External Tank, and the need to prevent damage to the delicate thermal protection tiles, the five-engine variant of the Saturn-Shuttle would require the center engine to be shut down 45 to 50 seconds after launch, while two of the outboard engines would have to be shut down prior to staging. Once the S-IC was jettisoned, the three onboard high-energy SSMEs would then propel the Orbiter into LEO, shutting down 6½ minutes after ignition. The external tank would then be jettisoned, as like that on the current Shuttle configuration and the Orbiter will then perform its mission.

But because of the need to keep costs down and to allow President Richard Nixon to approve the Shuttle program in 1972, NASA decided to utilize segmented Solid Rocket Boosters similar to those used on the Titan III rocket instead of the S-IC, thus killing the Saturn program after the initial Saturn V order was completed. If the Saturn-Shuttle configuration was used, it would have kept Saturn V, Saturn INT-20, and Saturn INT-21 in production, thus preventing the "Challenger" Disaster (caused by an O-ring failure) and launching a Skylab or Mir version of the International Space Station, or a realization of Space Station Freedom, by the mid-1980's. In addition, improvements to the F-1 engines would have allowed a throttlable, and possible reusable version, allowing the Shuttle to carry more payload into orbit.

References

* [http://www.astronautix.com/lvs/satuttle.htm Saturn Shuttle (Astronautix)]