Saturn V

Saturn V
Saturn V launching Apollo 15.
Stages		2 or 3
1 - S-IC	Engines	5 * F-1
Thrust		33,400 kN (7,500,000 lb) (later 33,900 kN)
Burn time		~165 s
Fuels		RP-1/LOX
2 - S-II	Engines	5 * J-2
Thrust		5,000 kN (1,125,000 lb) (later 5,100 kN)
Burn time		~380 s
Fuels		LH2/LOX
3 - S-IVB	Engines	1 * J-2
Thrust		890 kN (200,000 lb) (later 1,000 kN)
Burn time		~475 s (usually 2 burns)
Fuels		LH2/LOX
Two stage version
Payload to LEO		75,000 kg
Three stage version
Payload to LEO		118,000 kg
Payload to TLI		47,000 kg

The Saturn V (popularly known as the Moon Rocket) is a multistage liquid-fuel expendable rocket used by NASA's Apollo and Skylab programs. It was the ultimate design of the Saturn family of rockets designed under the direction of Wernher von Braun.

In 1961, when President Kennedy announced that America would try to get to the moon by the end of the decade, there was nothing in the United States arsenal (or in fact anywhere in the world) that could launch a manned spacecraft to the moon in one piece. The Saturn I was in development but had not flown and would require several launches to place in orbit all the components of the manned launch spacecraft.

In was announced on January 10, 1962 that NASA would build the Saturn V, though at that stage it was called the Saturn C-5. It would use the F-1 and J-2 rocket engines for propulsion and be designed by the Marshall Space Flight Center in Huntsville, Alabama.

It was decided early on to attempt to use as much technology from the Saturn I program as possible. As such the S-IVB third stage of the Saturn V was based on the S-IV second stage of the Saturn I. The Instrument Unit that controlled the Saturn V was also based on that carried by the Saturn I.

Over 110 m high and 10 m in diameter, with a total mass of 3,038,500 kg and a payload capacity of 118,000 kg to LEO, the Saturn V is the biggest and most powerful rocket ever built, although the Soviet Energiya heavy-lift booster was designed to orbit 120-150 tons, but was never flown at this capacity.

Saturn V is composed of three-stages:

• First Stage: S-IC built by Boeing
• Second Stage: S-II built by North American Aviation
• Third Stage: S-IVB built by Douglas Aircraft Company

Saturn V is the vehicle that carried the Apollo astronauts to the Moon. Launched from Launch Complex 39 at the John F. Kennedy Space Center the first stage would burn for 2.5 minutes lifting the rocket to 61 km and accelerated to a speed of 8600 km/h. In the process it has used 2 million kg of propellant.

The second stage now takes over burning for 6 minutes and reaching a speed of 24,600 km/h. The rocket is now at 185 km and nearly at orbital velocity. The thrid stage now burns for a further 2.5 minutes. It is about 12 minutes after launch. The third stage is kept attached while the spacecraft orbits the Earth two and a half times during which the spacecraft and rocket are checked out to make sure everything is in working order.

Then the third stage is reignited at Trans Lunar Injection (TLI) to send the spacecraft to the moon. It burns for over 5 minutes so that it reaches 39,400 km/h or over 10 km/s. A couple of hours after TLI, the Apollo Command Service Module (CSM) separates from the third stage turns 180 degrees and docks with the Lunar Module (LM) which rides below the CSM during launch. The CSM and LM then separate from the third stage.

The final act for the Saturn V rocket now is to be targeted away from the CSM and LM. At the moment it is on the same trajectory as the spacecraft and could present a hazard later in the mission. So the remaining propellant in its tanks in vented out of the engine. It can then be targeted either into a solar orbit or as in the case of the third stages from Apollo 13 onwards directed to impact the moon. These impacts were detected by seismometers left on the moon by previous missions and used to probe the inside of the moon.

Apart from manned lunar flights the Saturn V was used to launch the Skylab space station in earth orbit. Skylab was a modified third stage of a Saturn V and as such for its last flight, the rocket flew with only two stages.

The Space Shuttle was initially conceived of as a cargo transport to be used in concert with the Saturn V. The Shuttle would handle Space Station logistics, while Saturn V would launch components. Lack of funding for a second Saturn V production run killed this plan and left the US without a heavy-lift booster for the next 30 years (and counting).

There were also plans for a larger rocket called Nova that would have featured eight F-1 engines in its first stage allowing it to launch a manned spacecraft on a direct ascent flight to the moon. Other plans for the Saturn V called for using a Centaur as an upper stage or adding strapon boosters. These enhancements would have increased its ability to send large unmanned spacecraft to the outer planets or manned spacecraft to Mars.

Saturn V Vehicles and Launches

Currently there are three Saturn Vs on display:

• At the Johnson Space Center made up of first stage of SA-514, the second stage from SA-515 and the third stage from SA-513
• At the Kennedy Space Center made up of S-IC-T and the second and third stages from SA-514
• At the US Space & Rocket Center, Huntsville, Alabama made up of S-IC-D, S-II-F/D and S-IVB-D (all test stages not meant for actual flight)

Suggested Reading

• Bilstein, Roger E. (1980). Stages to Saturn: A Technological History of the Apollo/Saturn Launch Vehicles. NASA SP-4206. ISBN 0-16-048909-1.
  • Available for reading on-line: http://history.nasa.gov/SP-4206/sp4206.htm
  • and in softcover through the U.S. Government Printing Office: http://history.nasa.gov/gpo/order.html

Launch of the last Saturn V rocket carrying the Skylab space station