Level 3 Applied Science Unit 16 Assignment C
Emma Padgett
C1: Spacecraft Design
Apollo 11
The Apollo 11 had a primary objective to complete a national goal
set by John. F . Kennedy on May 25th 1961: To perform a crewed
lunar landing and return to earth. It launched on July 16th 1969,
carrying Commander Neil Armstrong, Commander Module Pilot
Michael Collins and Lunar Module Pilot Edwin Aldrin. They spend 21
hours on the moon’s surface. This mission launched aboard the
Saturn V rocket.
Materials and Properties
Rockets need four forces to withstand at all times during take off:
Thrust, weight, drag and lift. The frame of the rocket is usually made
from strong but light weighted materials like titanium or aluminium.
These employ stringers, which run from top to bottom connected by
hoops which run around the circumference. The skin is coated with
thermal protection system to keep the heat for air friction during
flight and keep in the cold temperatures needed for certain fuels and
oxidisers. Fins are attached to the bottom of the frame to provide
stability during flight.
Power
The F-1 is a rocket engine the was developed in the USA in the late
1950s. Five of these engines were used in Saturn V which is the main
Apollo Launch Vehicle. The F-1 however is the most powerful single
combustion chamber liquid propellant rocket engine ever developed.
Saturn V
Saturn V rockets used for the Apollo missions had three stages, Each
stage would burn its engines until it was out of fuel and would
separate itself from the rocket.
,The first stage had the most powerful engines, with 204,000 gallons
of kerosene and 318,000 gallons of oxygen, as these needed to get
the rocket off the ground and lift the rocket 42 miles .
The second stage carried on from there, leading the spacecraft
almost outside the orbit, with 260,000 gallons of liquid hydrogen and
80,000 gallons of oxygen. This is then fully-accomplished by the third
stage, when 66,7000 gallons of hydrogen and 19,369 gallons of
oxygen are used.
Space Radiation
Outside the protective cocoon of the Earth’s atmosphere is a
universe full of radiation. All these kinds of space radiation represent
ionizing radiation:
1. Particles trapped in the Van Allen Belts
2. Particles shot into space during solar flares
3. Galactic Cosmic Rays
The spacecraft had thin aluminium hull. This blocked some of the
radiation but not a lot.
Service Module: Electrical Power Supply
The Apollo command Module’s primary source of electric power was
from a set of three “fuel cells” housed in the Service Module. Each of
the cell combines hydrogen and oxygen to produce electricity and
water. Normal power output for each power plant is 563 to 1420
watts, with a maximum of 2300 watts.
Apollo 13
During the April 1970 lunar landing, one of the oxygen tanks failed
and the mission had to be shut down. One of the tanks ignited and
damaged wires inside of it causing an explosion, leading to cut off of
the life support systems. At this point, the mission controllers
worked on bringing the crew home alive and they used the LM as a
lifeboat.
, Micro-meteorites
These can be a significant threat to any space exploration. Long term
exposure can threaten space craft’s functionality. Several materials
were on the apollo surface to protect it.
Heat Shields
A material called AVOCAT is used on the Apollo for heat protection.
The shield is covered in titanium truss, layered in carbon fibres. The
ablative heat shield protected the capsule from re-entry heat. The
material charred and melted away and carried away the intense heat
in the process. It contains many layers to ensure everything inside is
safe. There was a fatal incident in USA Space Shuttle program that
occurred February 1st 2003. When the shuttle re-entered the
atmosphere the seven crew members were killed after the heat
shield was damaged on the wing.
C2: Spaceflight Practicalities
Lift off
Newton’s 1st law of motion states that if two forces acting on a body
are balanced then there will be zero resultant force. The body will
remain at rest or keep moving in a straight line at a constant speed/
The rocket will then remain on the launch pad whilst the forces
acting on it remain balanced. The resultant force is equal to zero
because normal reaction = weight.
Newtons 2nd law states that when a resultant force acts on a body, it
produces an acceleration in the body in the direction of the resultant
force. When the rocket engine ignites, thrust is produced. When this
thrust is greater than the weight of the rocket, the forces become
unbalanced and produces a resultant force:
thrust – weight = resultant force
As the rockets velocity increases, the air resistance force, that is
acting on the rocket, increases.
