# Apollo 13: Liftoff and Rocket Stages **URL:** \ **Category:** Factual Questions\ **Created:** [June 6, 2000, 1:19pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540 "2000-06-06T13:19:40Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [June 6, 2000, 1:19pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540/1 "2000-06-06T13:19:40Z")
a) Lift-off: What was all the “junk” appearing to be breaking off the skin of the Saturn V rocket? I can understand explosion bolts, but this looked like something more - like ceramic tiles falling off (but I don’t think the skin of the Saturn V has anything of the sort). Does anyone have a WAG? Or, is this just Hollywood effects? (Footage could have been a mix of actual and model.) b) Stages: How do the rocket stages fall off? Is it some kind of automatic response? If so, how exactly? Also, how does the nosecone, atop the rocket, jettison? Is this also an autonomous act? ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [June 6, 2000, 1:26pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540/2 "2000-06-06T13:26:35Z")
Most of the junk falling off of the booster was ice. The booster is a thin metal skin containing large tanks of liquid oxygen (LOX), which is rather cold. Being in a humid environment like Florida, water condensed and froze on the structure. When the ship took off, the ice was dislodged. I’m pretty sure the stage seperation was programmed. The “nosecone” was attached to the escape rocket. When the rocket was jettisoned, the cover went with it. I don’t know if that was jettisoned manually; or if it was programmed to jettison automatically. The purpose was to pull the Apollo module clear of the booster and CM in case of an emergency. It was never used for that purpose. ---
**Author:** ![Thing\_1](https://avatars.discourse-cdn.com/v4/letter/t/ce73a5/32.png) [@Thing\_1](https://boards.straightdope.com/u/Thing_1)\ **Post date:** [June 6, 2000, 1:31pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540/3 "2000-06-06T13:31:41Z")
Jinx, For more information than you could want you might try looking at [http://www.spaceline.org](http://www.spaceline.org). They have a lot of information regarding the Apollo program and the hardware used. John ---
**Author:** ![Groundskeeper\_Willie](https://avatars.discourse-cdn.com/v4/letter/g/eb9ed0/32.png) [@Groundskeeper\_Willie](https://boards.straightdope.com/u/Groundskeeper_Willie)\ **Post date:** [June 6, 2000, 1:35pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540/4 "2000-06-06T13:35:00Z")
> [@](#): > > a) Lift-off: What was all the “junk” appearing to be breaking off the skin of the Saturn V rocket? I can understand explosion bolts, but this looked like something more - like ceramic tiles falling off (but I don’t think the skin of the Saturn V has anything of the sort). It’s frost. The Saturn V used liquid oxygen on all three stages, as well as liquid hydrogen on the second and third stages. Since each stage was basically a set of giant fuel/oxidiser tanks, atmospheric humidity would freeze onto the sides , and break loose during liftoff. > [@](#): > > b) Stages: How do the rocket stages fall off? Is it some kind of automatic response? If so, how exactly? Explosive charges would separate the stages. I believe that the onboard ICU (inertial guidance unit) would control the timing of staging, but I’m not sure. Bill ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [June 6, 2000, 1:35pm UTC](https://boards.straightdope.com/t/apollo-13-liftoff-and-rocket-stages/21540/5 "2000-06-06T13:35:03Z")
Thanks to all for the facts! Very interesting! I didn’t even think about the condensate/ice build-up! Cool!