View Full Version : Apollo 15 and heat

Peter B
2002-Jan-02, 05:52 AM
I was browsing through the Apollo 15 Flight Journal on NASA’s website. Within this impressively long and detailed document I happened across the following quote, which seems to be relevant to an earlier (now locked) thread about a spacecraft in sunlight. It related to the last few hours of the flight when the Command Module had separated from the Service Module, yet had most of its systems switched on in preparation for re-entry.

“During these preparations, virtually all of the Command Module systems are powered up. The heat generated by these systems is readily handled by the thermal control systems (part of the Environmental Control System) within the Service Module. Under moderate power loads, the heat from the Command and Service module systems is absorbed by a water-glycol solution (not unlike that which is found in the radiator of an automobile) and is rejected to space through a series of radiators located on the upper panels of the Service Module. A water evaporator system, similar in principle to that of the PLSS sublimators (the Portable Life Support System, worn by the crews on the lunar surface), is also available to remove larger amounts of heat.

“Unfortunately, once the Command and Service Modules separate prior to entry, the elaborate heat dissipation systems used by the Command Module float away with the rest of Service Module. A special provision must be made, therefore, to manage the heat generated within the Command Module during the 30 minutes between separation and splashdown.”

2002-Oct-16, 02:11 PM
On 2002-01-02 00:52, Peter B wrote: To:
7:21 A.M. PDT October 16, 2002
pushed to page one from page 24

2002-Oct-16, 04:23 PM
They took their coats off?

2002-Oct-16, 05:08 PM
On 2002-10-16 12:23, johnwitts wrote:
They took their coats off?

Nah, they just needed to open a window.

2002-Oct-16, 05:53 PM
The answer it the classic heat sink: a reasonably large volume of water-glycol coolant is contained in reservoir in the CM. Prior to re-entry this reservoir is chilled. Then heat from the coolant loop is transferred to this volume of water, which gradually warms. When the crew lands, they have a nice, cool spacecraft and a pot of hot water for making tea.

2002-Oct-16, 07:56 PM
IIRC, a hot shower was more on top of the post-landing priority list...

2002-Oct-16, 09:18 PM
A hot cup of tea made from glycol coolant. Sounds nice.

2002-Oct-16, 10:23 PM
What, isn't that how tea is made in the U.K.?

2002-Oct-16, 11:32 PM
Ethylene Glycol Tea? Sure, we all drink it. Keeps us cool in the Summer and warm in the Winter.

***Disclaimer: Don't drink tea made with Ethlyene Glycol. It sends your teeth a funny colour.

And you die.

2002-Oct-17, 06:52 AM
In 1985, we had the Austrian Diethylene Glycol Scandal when it came out that a big wine merchant mixed wine with diethylene glycol to "improve" its quality...

2002-Oct-17, 11:35 AM
On 2002-10-17 02:52, kucharek wrote:
In 1985, we had the Austrian Diethylene Glycol Scandal when it came out that a big wine merchant mixed wine with diethylene glycol to "improve" its quality...

{uh?HU} & how many ?"BROWSE"? points was that good4
------ speaking of Mark.it points
in these threads yesterday I linked to the
Routers{check4spelling} {as a string} in the
thread about the Russian{SoVieT} Missle blow up/
and then the DOW lost 200 {well never mind ? MAYBE}