The F-1 is the Rocketdyne engine that powered the Saturn V first stage, five to a rocket.
nasa-rocketdyne-f-1 Rocketdyne, a division of North American Aviation, built the F-1 for NASA. Each engine burned RP-1 kerosene with liquid oxygen and produced about 1.5 million pounds of thrust. Five of them powered the first stage of the Saturn V, which lifted Apollo spacecraft off the pad. The first flight was the unmanned Apollo 4, on 9 November 1967.
The chamber wall is a bundle of tubes made of Inconel X-750, a nickel alloy built for high temperatures, with fuel running through them to cool the metal. The same fuel lubricates the pump bearings, so there is no separate lubrication system, and it doubles as the hydraulic fluid for the valves and steering actuators.
Five F-1 engines powered the Saturn V first stage (S-IC) that lifted Apollo spacecraft off the pad, burning RP-1 and liquid oxygen. The engine is a reference case for very large kerosene engines and for nickel-superalloy tube-wall thrust chambers; NIST studied recovered hardware to see how the Inconel X-750 changed under engine heat and decades in seawater.
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The chamber is a bell-shaped bundle of tubes, joined by brazing in a furnace. Brazing joins metal parts with a melted filler. Fuel flows through the tubes and cools the wall. The 178 primary tubes form the upper part, and 356 smaller secondary tubes continue below. A ring-shaped steel manifold carries the turbine exhaust.
The injector is a corrosion-resistant steel plate fitted with copper rings, fourteen for fuel and fifteen for oxygen, each drilled with small holes. Two circular and twelve radial baffles, cooled by fuel, split the face into thirteen compartments to keep the burn steady. Development tested 15 baffle designs and 14 injector configurations.
Below the tube-walled bell, a welded double-wall skirt of nickel-base alloy extends the nozzle. Turbine exhaust gas is injected along its inner wall as a cooling film. Steel channel bands are welded around the outside to stiffen it, and asbestos blankets insulate the exit end.
One shaft carries the oxygen pump at the top, the fuel pump below it and the turbine beneath that. Hot gas from a gas generator drives the turbine. Its welded housing is René 41, a high-nickel alloy. Cracks appeared in development and were traced to an improper welding process.
One oxygen valve and one fuel valve sit on each side of the engine, sealed with machined Teflon. A cartridge of self-igniting fluid, 85 percent triethylborane and 15 percent triethylaluminium, starts the engine without a pyrotechnic igniter. A spherical steel joint lets the four outer engines swivel.
The bundle of chamber tubes. NIST examined recovered chambers and found that engine heat had changed the metal's internal structure.
The injector's fuel and oxygen orifice rings, and its fuel-cooled circular and radial baffles.
The turbine housing. Cracks in it were traced to an improper welding process during development.
Inner and outer walls of the nozzle extension, and part of the welded oxygen dome.
The injector plate, the turbine exhaust manifold, the nozzle's reinforcing bands and part of the oxygen dome.
Blankets on the exit end of the nozzle extension, and layered insulators reinforced with Inconel wire.
Five F-1 engines sat at the base of the Saturn V first stage, called the S-IC. The four outer engines swivelled to steer the rocket, and the centre engine stayed fixed. Rocketdyne built all 98 production engines, and 70 of them were tested in S-ICs. The F-1 followed Rocketdyne's earlier S-3D and H-1 engines in its propellants, packaging, chamber design and start sequence.
NASA
Five F-1 engines at the base of the S-IC; four outer engines gimbaled, centre engine fixed
Grumman / NASA
Five on the Saturn V S-IC first stage; Saturn V first-stage engines under the stack that carried the LM; launcher engine, not carried by the vehicle
North American Aviation
Five on the Saturn V S-IC first stage; Saturn V first-stage engines; launcher engine, not carried by the vehicle
F-1 followed their propellant choice, packaging, chamber design, gas generator cycle and start sequence
Engine builder; NASA approved contract NAS8-18734 for 30 F-1 engines in 1966
North American Aviation
asbestos. Here: Exit-end insulation blankets; Asbestos blanket insulators. There: Thruster thrust-chamber insulation.
Inconel. Here: Turbine honeycomb seal; Foil-batt insulators. There: Cryogenic oxygen tanks; Q-ball instrument package and Inconel nose cone.
Aluminium. Here: High-pressure propellant ducts. There: Radial beams; Crushable ribs (x4) and more.
steel. Here: Gimbal bearing. There: Crew couch frames (x3); Couch shock-attenuating struts (x8).
Grumman / NASA
Inconel. Here: Turbine honeycomb seal; Foil-batt insulators. There: Plume-exposed shield areas; RCS plume deflector.
Teflon. Here: Main oxidizer valve poppet seal; Main fuel valve poppet seal. There: Inner window seal jacket.
Aluminium. Here: High-pressure propellant ducts. There: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more.
Aerojet Rocketdyne
Teflon. Here: Main oxidizer valve poppet seal; Main fuel valve poppet seal. There: Duct flange seals (Teflon-coated conical washers).
Aluminium. Here: High-pressure propellant ducts. There: Fuel pump inducer, impellers and body; Turbine blades, disks and hub and more.
carbon. Here: Carbon shaft seals. There: Shaft seals.
Rocketdyne
Copper. Here: Fuel orifice rings (14); Oxidizer orifice rings (15) and more. There: Original injector (flat-faced).
Teflon. Here: Main oxidizer valve poppet seal; Main fuel valve poppet seal. There: Hydrogen seals at duct flanges and pipe joints.
liquid oxygen. Here: Oxidizer. There: Oxidizer.
Rockwest Composites
Copper. Here: Fuel orifice rings (14); Oxidizer orifice rings (15) and more. There: Copper traces in the skins.
Aluminium. Here: High-pressure propellant ducts. There: Aluminium inserts, in-plane and out-of-plane (DiskSat build).
PSAS / Oregon State
Copper. Here: Fuel orifice rings (14); Oxidizer orifice rings (15) and more. There: Helical antenna (+Z end card); Outer copper foil and more.
Aluminium. Here: High-pressure propellant ducts. There: Backplane grounding to frame.
The published description names many materials but few grades. The corrosion-resistant steel and the nickel-base alloy have none, and the pump impellers, pump housings, braze and valve bodies are not described at all. Sources also disagree on size: 16 feet long in one, 18 feet tall in another.
What is written above is built from these numbers and quotes. Each row links to the page it was taken from. Get all of it as JSON, or ask our MCP server.
| What | Value |
|---|---|
| Sea-level thrust | About 1,522,000 lbf (uprated from 1.5 million lbf) |
| Original thrust rating | 1.5 million lbf per engine |
| Specific impulse | 265 s |
| Chamber pressure | 1,100 psi (design) |
| Propellants | Liquid oxygen and RP-1 kerosene |
| Cycle | Gas generator |
| Nozzle area ratio | 16:1 (tube wall to 10:1, double-wall extension to 16:1) |
| Dry mass | About 18,500 lb |
| Envelope (EngineHistory.org) | 12 ft diameter by 16 ft long |
| Envelope (Biggs, Rocketdyne) | 18 ft tall, 12 ft wide |
| Burn time | 165 s per flight |
| Qualification life | 20 starts and 2,250 s |
| Turbopump layout | One shaft: LOX pump, fuel pump, turbine |
| Engines per vehicle | 5 on the Saturn V S-IC first stage (4 outer engines gimbaled, centre engine fixed) |
| Production | 98 production engines |
| Contract | NASA contract NAS8-18734 for 30 F-1 engines (approved 18 Nov 1966) |
| First flight | 9 November 1967, Apollo 4 (AS-501), first Saturn V |
| First flight date | 1967-11-09 |
Each material named in the sources: where it is used here, which other products use it, and its key numbers when its material page exists.
Used in 4 partsFuel orifice rings (14) · Oxidizer orifice rings (15) · Circular baffles (2) · +1 more
Used in 4 partsTurbine exhaust manifold · Injector plate (31 rings, 13 compartments) · Dome body and torus manifold, CRES parts · +1 more
Used in 3 partsChamber tube bundle (178 primary and 356 secondary tubes) · Secondary tubes (356) · Dome-to-injector inner O-ring
Used in 2 partsExit-end insulation blankets · Asbestos blanket insulators
Used in 2 partsTurbine honeycomb seal · Foil-batt insulators
Used in 2 partsDome body and torus manifold, nickel-base alloy parts · Nozzle extension inner and outer walls
Used in 2 partsMain oxidizer valve poppet seal · Main fuel valve poppet seal
Used in 1 partHigh-pressure propellant ducts
Used in 1 partCarbon shaft seals
Used in 1 partGimbal socket liner
Used in 1 partOxidizer pump wear ring
Used in 1 partFuel pump wear rings
Used in 1 partOxidizer
Used in 1 partTurbine housing
Used in 1 partFuel
Used in 1 partGimbal boot
Used in 1 partGas generator hot-gas seals
Used in 1 partGimbal bearing
Used in 1 partDome-to-injector flange gasket
Used in 1 partHypergolic igniter fluid
Used in 1 partDome-to-injector outer O-ring
Part lists and materials come from the Rocketdyne-derived F-1 description (EngineHistory.org Part 8.12), its history page (Part 8.11), NASA SP-2009-4545 and NIST. Chamber tubes, injector, dome, nozzle extension, seals, gimbal, ducts and insulation have a stated material; turbopump rotors, pump housings (except the Rene 41 turbine housing), braze alloys and valve bodies do not.
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Chamber tube bundle (178 primary and 356 secondary tubes)“constructed of a nickel-based superalloy called Inconel X-750” | Inconel X-750 (nickel-based superalloy)inconel-x-750 | — | NIST describes recovered thrust chambers and the exhaust nozzle; EngineHistory.org prints the tubing as Inconel-X |
| Primary tubes (178)“A total of 178 primary tubes, each hydraulically formed” | Not said | — | — |
| Secondary tubes (356)“Inconel-X secondary tubes formed the chamber from the 3:1 to the 10:1 expansion ratio plane” | Inconel-Xinconel-x-750 | — | — |
| Tube-to-tube joints“The thrust chamber body was a furnace-brazed, bell-shaped assembly” | Not said | — | — |
| Turbine exhaust manifold“a corrosion resistant steel (CRES) torus” | corrosion-resistant steel (CRES)cres-corrosion-resistant-steel | — | — |
| Dome-to-injector flange gasket“The dome and injector mating flanges were sealed by a Teflon-filled Flexitallic gasket.” | Teflon-filled Flexitallic gasketteflon-filled-flexitallic-gasket | — | — |
| Dome-to-injector inner O-ring“at the inner diameter by a hollow Inconel-X O-ring” | Inconel-Xinconel-x-750 | — | — |
| Dome-to-injector outer O-ring“sealed at the outer diameter by a Viton-A O-ring” | Viton-Aviton-a | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Injector plate (31 rings, 13 compartments)“It was a CRES, 31-ring, plate-type injector, divided into 13 compartments by 2 circular and 12 radial baffles.” | corrosion-resistant steel (CRES)cres-corrosion-resistant-steel | — | — |
| Fuel orifice rings (14)“Fourteen copper rings, orifice-drilled to provide a doublet fuel-on-fuel impingement” | coppercopper | — | — |
| Oxidizer orifice rings (15)“Fifteen copper rings, orificed-drilled to provide a doublet oxidizer-on-oxidizer impingement” | coppercopper | — | — |
| Circular baffles (2)“two circular, fuel-cooled copper baffles were brazed to the fuel ring grooves” | coppercopper | — | — |
| Radial baffles (12)“The twelve radial, fuel-cooled, copper baffles were supplied with fuel by the outer circular baffle” | coppercopper | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Dome body and torus manifold, CRES parts“The assembly was a welded, CRES and nickel-base alloy unit consisting of a dome body and a torus manifold.” | corrosion-resistant steel (CRES)cres-corrosion-resistant-steel | — | Shares one quote with the nickel-base alloy portion below |
| Dome body and torus manifold, nickel-base alloy parts“The assembly was a welded, CRES and nickel-base alloy unit consisting of a dome body and a torus manifold.” | nickel-base alloy (grade not stated)nickel-based-alloy | — | Source does not say which parts are CRES and which are nickel-base alloy |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Nozzle extension inner and outer walls“The nozzle extension was of welded construction, incorporating nickel-base-alloy inner and outer walls” | nickel-base alloy (grade not stated)nickel-based-alloy | — | Inner wall film-cooled by turbine exhaust |
| Reinforcing channel bands“CRES reinforcing channel bands welded to the outer wall circumference” | corrosion-resistant steel (CRES)cres-corrosion-resistant-steel | — | — |
| Exit-end insulation blankets“Asbestos blankets were used on the exit end of the nozzle extension” | asbestosasbestos | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Gas generator combustor“The gas generator combustor was a welded single-walled manifold connecting the gas generator injector and the turbine inlet.” | Not said | — | — |
| Gas generator thermal shell“The combustor was thermally insulated by a sheet metal shell that bolted around the combustor body.” | Not said | — | — |
| Gas generator hot-gas seals“silver-plated stainless-steel Naflex and K-seals and copper crush washers for hot-gas applications” | silver-plated stainless steelsilver-plated-stainless-steel | — | Copper crush washers used with them |
| Heat exchanger (LOX and helium coils)“using a heat exchanger to vaporize LOX and heat helium to pressurize the LOX and RP-1 tanks” | Not said | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Main oxidizer valves (2)“There were two LOX valves, one on each side of the engine” | Not said | — | — |
| Main oxidizer valve poppet seal“a poppet with a machined Teflon seal secured by a seal retainer” | Teflonteflon-ptfe | — | — |
| Main fuel valves (2)“and two fuel valves, one on each side of the engine as well” | Not said | — | — |
| Main fuel valve poppet seal“a spring-loaded poppet with a machined Teflon seal secured by a seal retainer” | Teflonteflon-ptfe | — | — |
| High-pressure propellant ducts“The ducts were constructed of drawn aluminum tubing, bent in a continuous section.” | aluminum tubing (alloy not stated)aluminium | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Hypergolic igniter fluid“pyrophoric fluid consisting of 85% triethylborane and 15% triethylaluminum” | triethylborane 85% and triethylaluminum 15% pyrophoric fluidtriethylborane-triethylaluminum | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Gimbal bearing“The assembly was a spherical, low-friction, steel universal joint” | steel (grade not stated)steel-grade-unstated | — | — |
| Gimbal socket liner“A composition of Teflon-impregnated fiberglass (Fabroid) was bonded to the bearing surfaces of the sockets.” | Fabroid (Teflon-impregnated fiberglass)fabroid | — | — |
| Gimbal boot“A silicone-impregnated fiberglass boot” | silicone-impregnated fiberglasssilicone-impregnated-fiberglass | — | — |
| Foil-batt insulators“constructed of random fiber batting secured between two layers of textured inconel foil” | Inconel foil over random fibre battinginconel | — | — |
| Asbestos blanket insulators“Asbestos blanket insulators were composed of multiple layers of asbestos cloth reinforced with Inconel lockwire” | asbestos cloth with Inconel lockwireasbestos | — | — |
| Part | Material | Finish and standard | Made by |
|---|---|---|---|
| Oxidizer“five F-1 rocket engines that burned a combination of RP-1 and LOX” | liquid oxygen (LOX)liquid-oxygen | — | — |
| Fuel“five F-1 rocket engines that burned a combination of RP-1 and LOX” | RP-1 kerosenerp-1-kerosene | — | — |
No alloy grades except Inconel X-750 (NIST) and Rene 41; CRES and nickel-base alloy are printed without a grade. No standards.
Maker credit: Rocketdyne, Division of North American Aviation (for NASA). Collected from public pages and documents, checked 4 Nov 2026.
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