The S-I was the first stage of the

Saturn I The Saturn I was a rocket designed as the United States' first medium lift launch vehicle for up to low Earth orbit payloads.Terminology has changed since the 1960s; back then, 20,000 pounds was considered "heavy lift". The rocket's first stag ...

rocket used by NASA for the Apollo program.

Design

The S-I stage was powered by eight H-1

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accordanc ...

s burning

RP-1 RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. RP-1 provides a lower specific impulse than liquid hydrogen (LH2), but is cheaper, is st ...

fuel with

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an applica ...

(LOX) as oxidizer. The design of the S-I was based on Jupiter and Redstone tanks to leverage existing chains. A central

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...

tank was surrounded by a cluster of eight Redstone tanks. Four of these Redstone tanks contained LOX and four contained RP-1. The outer tanks were painted to alter thermal conditions inside the tanks and to provide a "roll pattern" used to estimate radial motion during flight. The engines were arranged in two clusters, a group of four fixed central engines and a group of four outer gimbled engines. The gimbles allowed the stage to be controlled with

thrust vectoring Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the v ...

. On launches after SA-5, eight fins were added to enhance control during atmospheric flight.

History

The S-I stage was developed by Chrysler and consisted of 9 tanks that were previously used on existing rockets. The central tank was a

tank that held the liquid oxygen. This Jupiter tank was sounded by eight Redstone tanks. four of these contained liquid oxygen and the other four held RP-1. The first four launches had no fins on the S-I, but the remaining six added them to improve stability during atmospheric flight. The initial launch of the Saturn I consisted of an active S-I, an inactive S-IV and inactive S-V stage. Tensions were high as a launch vehicle of this size had never flown before. The S-I was partially loaded with propellent to lessen the destruction if an anomaly occurred near or on the pad. In the end, the launch was successful and the subsequent SA-5 launch was identified by

JFK John Fitzgerald Kennedy (May 29, 1917 – November 22, 1963), often referred to by his initials JFK and the nickname Jack, was an American politician who served as the 35th president of the United States from 1961 until his assassination i ...

as the launch that put the U.S. above the USSR in terms of lift capability.

Flight history

References

{{reflist Rocket stages NASA space launch vehicles