SpaceOdysseyHub · Mission Worksheet

Apollo 13: Failure Is Not an Option

Ages 11–14 · Ages 14–18 · 40 min · spaceodysseyhub.com/replays/apollo-13

Name: Date:

Mission objectives

Reconstruct the sequence of events from the oxygen tank failure to splashdown
Explain how the Lunar Module served as a lifeboat and why its systems were pushed past design limits
Practice engineering problem-solving under constraints (the CO₂ scrubber adapter)
Evaluate why Apollo 13 is called a 'successful failure'

1.List the chain of events in order: tank stir → ? → ? → move to LM. Fill in the two missing steps.short answer
2.The LM was built to keep 2 people alive for about 2 days. It kept 3 people alive for about 4 days. Roughly how many 'person-days' is each — and what does the difference tell you?calculation
3.During one stop-point, write down two things you notice about HOW the crew and Mission Control talk to each other.observation
4.You're a flight controller. Water is rationed to one-fifth of normal. Argue for one other thing you would sacrifice to save power, and defend the choice.discussion
5.In your own words: why is Apollo 13 called a 'successful failure'?short answer

free-return trajectory: — A path that uses the Moon's gravity to sling a spacecraft back toward Earth without a major engine burn.
Lunar Module (LM): — The two-person lander — on Apollo 13, used as a lifeboat for three astronauts.
CO₂ scrubber: — A canister of lithium hydroxide that removes exhaled carbon dioxide from cabin air.
Mission Control: — The team in Houston that monitored the spacecraft and worked every problem alongside the crew.
re-entry blackout: — The minutes when ionized air around the returning capsule blocks all radio contact.

Teacher answer key — do not photocopy with page 1

1.Tank stir → oxygen tank 2 explodes → fuel cells lose oxygen, power and water fail → crew moves into the LM.
2.Designed: ~4 person-days (2×2). Flown: ~12 person-days (3×4) — about 3× the design, showing how much hidden margin and rationing made possible.
3.Open response — no fixed answer.
4.Open response — no fixed answer.
5.The mission failed its goal (no Moon landing) but succeeded at something harder — bringing the crew home alive through improvisation, teamwork, and engineering margin.

What failed first on Apollo 13? — An oxygen tank in the Service Module
Why did the crew move into the Lunar Module? — It became a lifeboat with its own power, oxygen, and engine
The 'mailbox' the crew built from flight-plan covers, bags, and tape solved which problem? — Fitting square CO₂ scrubber canisters to round sockets
How did Apollo 13 get home without its main engine? — It flew around the Moon on a free-return trajectory, adjusted with the LM's engine
When did Apollo 13 fly? — April 1970