S-IC

S-IC

The Apollo 10 S-IC stage is hoisted in the VAB for stacking
Fact sheet
Height	42 m (138 ft)
Diameter	10 m (33 ft)
Mass	2,280,000 kg (5,030,000 lb)
Engines	5 F-1 engines
Thrust	33,400 kN (7,500,000 lbf)
Burn time	150 s
Fuel	RP-1 and liquid oxygen

The S-IC (pronounced "ess one see") was the first stage of the American Saturn V rocket. The S-IC stage was built by the Boeing Company. Like the first stages of most rockets, most of its mass of more than 2,000 tonnes at launch was propellant, in this case RP-1 rocket fuel and liquid oxygen (LOX) oxidizer. It was 42 meters tall and 10 meters in diameter, and provided 33,000 kN of thrust to get the rocket through the first 61 kilometers of ascent. The stage had five F-1 engines in a quincunx arrangement. The center engine was fixed in position, while the four outer engines could be hydraulically gimballed to control the rocket.

Manufacturing

The Boeing Co. was awarded the contract to manufacture the S-IC on December 15, 1961. By this time the general design of the stage had been decided on by the engineers at the Marshall Space Flight Center (MSFC). The main place of manufacture was the Michoud Assembly Facility, New Orleans. Wind tunnel testing took place in Seattle and the machining of the tools needed to build the stages at Wichita, Kansas.

MSFC built the first three test stages (S-IC-T, the S-IC-S, and the S-IC-F) and the first two flight models (S-IC-1 and -2). They were built using tools produced in Wichita.

It took roughly seven to nine months to build the tanks and 14 months to complete a stage. The first stage built by Boeing was S-IC-D, a test model.

Components

Cutaway diagram of the S-IC

The largest and heaviest single component of the S-IC was the thrust structure, with a mass of 21 metric tons. It was designed to support the thrust of the five engines and redistribute it evenly across the base of the rocket. There were four anchors which held down the rocket as it built thrust. These were among the largest aluminum forgings produced in the U.S. at the time, 4.3 meters long and 816 kilograms in weight. The four stabilising fins withstood a temperature of 1100 °C.

Saturn V first stages S-1C-10, S-1C-11, and S-1C-9 at Michoud Assembly Facility

Above the thrust structure was the fuel tank, containing 770,000 liters of RP-1 fuel. The tank itself had a mass of 11 metric tons dry and could release 7300 liters per second. Nitrogen was bubbled through the tank before launch to keep the fuel mixed. During flight the fuel was pressurized using helium, that was stored in tanks in the liquid oxygen tank above.

Between the fuel and liquid oxygen tanks was the intertank.

Apollo 11 S-IC separation

The liquid oxygen tank held 1,305,000 liters of LOX. It raised special issues for the designer. The lines through which the LOX ran to the engine had to be straight and therefore had to pass through the fuel tank. This meant insulating these lines inside a tunnel to stop fuel freezing to the outside and also meant five extra holes in the top of the fuel tank.

Two solid motor retrorockets were located inside each of the four conical engine fairings. At separation of the S-IC from the flight vehicle, the eight retrorockets fired, blowing off removable sections of the fairings forward of the fins, and backing the S-IC away from the flight vehicle as the engines on the S-II stage were ignited.

Stages built

Serial number	Use	Launch date	Current location	Notes
S-IC-T	static test firing		part of Saturn V display at Kennedy Space Center
S-IC-S	structural load testing (had no engines)		location unknown (last seen at MSFC)
S-IC-F	facilities testing for checking out launch complex assembly buildings and launch equipment		location unknown
S-IC-D	ground test dynamics model		U.S. Space & Rocket Center, Huntsville, Alabama
S-IC-1	Apollo 4	November 9, 1967		Manufactured by MSFC
S-IC-2	Apollo 6	April 4, 1968		Manufactured by MSFC; carried TV and cameras on Boattail and Forward skirt
S-IC-3	Apollo 8	December 21, 1968		Manufactured by Boeing (as with all subsequent stages); weighed less than previously manufactured units allowing 36 kg more payload
S-IC-4	Apollo 9	March 3, 1969
S-IC-5	Apollo 10	May 18, 1969		Last flight for S-IC R&D Instrumentation
S-IC-6	Apollo 11	July 16, 1969		One or more engines recovered by a team financed by Jeff Bezos.
S-IC-7	Apollo 12	November 14, 1969
S-IC-8	Apollo 13	April 11, 1970
S-IC-9	Apollo 14	January 31, 1971
S-IC-10	Apollo 15	July 26, 1971
S-IC-11	Apollo 16	April 16, 1972
S-IC-12	Apollo 17	December 7, 1972
S-IC-13	Skylab 1	May 14, 1973		engine shutoff changed to 1-2-2 from 1-4 to lessen loads on Apollo Telescope Mount
S-IC-14	Unused		Saturn V display at Johnson Space Center	Scheduled for Apollo 18/19
S-IC-15	Unused		On display at Michoud Assembly Facility	Designated but never used as a backup Skylab launch vehicle

See also

• S-II
• S-IVB
• Apollo (spacecraft)

External links

• Stages to Saturn
• Apollo Saturn Reference Page
• Video of static test on YouTube