posted 12-30-2005 07:18 AM               

During reentries, however, some of the Kapton was peeled and/or broke away from the Command Module spacecrafts, especially during a return voyage to the moon. When this did occur, it would look as though -- in many instances -- that much of the "gold" surfaces were in fact part of the outside layers... and even more so when a bright sun was overhead during an ocean recovery.

posted 12-31-2005 04:48 AM               

Studying a photo of the command module recovery it seems that the golden colour appears to be caused by re-entry scorch marks. The lower section of the CM, near to the flotation collar, is very obviously silver.

posted 12-31-2005 11:45 AM               

I have seen Kapton from several other Apollo missions, and they all look the same. But the 'Kapton' from Apollo 17 is different from all of them (it does not have the gold backing, and it is thicker than the Kapton tape samples from the other missions).

It also appears that the underside is coated with a red adhesive that is not present in the other Kapton samples that I have seen.

posted 12-31-2005 01:24 PM            

The foil that is in the newer acrylics flown on Apollo 17 is not the exterior kapton polymide tape, it's a liner foil used under the outer ablator material and it's thicker than kapton foil. The thicker foil is silver on both sides, whereas the .00085 kapton foil is gold on the spacecraft side and silver on the outside surface.

posted 01-01-2006 06:31 PM               

The most extensive use of Kapton in space was on the Apollo Lunar Modules. Up to 27 layers of "Kapton" coated with a thin deposit of aluminum served as thermal insulation on the exterior of the moon ship.

This lightweight thermal control insulation protected both Apollo space vehicles from the extreme heat and cold of outer space by creating a multi-layer reflective barrier against the intense thermal insulation primarily because it does not burn, melt, or shrink excessively at high temperatures.

As an example of its ability to withstand heat: At 200 degrees C. -- a temperature at which most films have little tensile strength -- it would take 17,000 pounds per square inch of force to pull apart a sheet of Kapton one-thousandth of an inch thick.

posted 01-04-2006 08:35 AM               

In an earlier posting that I made a while back someone replied with a comment about Kapton... "The reflective color on the cone of Apollo was a thin layer applied over the thermal protection system to improve the reflection of radar tracking waves, to help tracking at lunar distance."

So, are both comments true? I can see where on the Lunar Module many layers were used, with space in between, which would act as an insulating layer. But, on the command module it was just one layer tightly sealed to the craft... which it would seem would eliminate any insulating abilities of it. Certainly, it would seem that the reflective abilities of this material would reflect dangerous waves from the Sun.

posted 01-06-2006 02:29 PM               

There is a NASA Technical Note (Report # TN D-7564) published in Jan. 1974 that discusses, in detail, about the whole Apollo Thermal Protection Subsystem that included the Kapton usage. As mentioned in some of my certification write-ups of the Du Pont-made thermal plastic film, the thermal control requirements for the Apollo ship modules in outer space necessitates a relatively low thermal absorbance-to-emittance ratio of 0.4 for the surface of the Command Module. This low ratio is achieved with a pressure-sensitive Kapton polyimide tape that is coated with aluminum and oxidized silicon monoxide. It was applied over, as you know, the entire external surface of the spacecraft's ablator.

Kapton was also used extensively in the Lunar Module and in the astronauts' suits made by ILC Industries. When Apollo astronauts explored the lunar surface, there were two inner layers of aluminized Kapton that helped protect the moonwalkers against temperatures from minus 250 degrees F. to 250 degrees F.

Another use of Kapton in space vehicles -- and still today in some instances -- is for electrical insulation on aerospace wire. The most extensive use was in the LM with more than 14 miles of wiring insulated with Kapton polyimide film.

Though Kapton has proven to be vital to space exploration, it was not developed specifically for that purpose. It is the result of a Du Pont Film Department exploratory research effort aimed at finding useful new materials. That effort began in 1955 at a Du Pont experimental station in Delaware and consisted of one chemist working in one laboratory.

posted 01-12-2006 07:48 PM               

But when viewed closeup it actually looks like this:

posted 07-14-2010 10:41 PM               

I assume in it's "naked" state it was white. Museum CMs show specs of a white surface after all the burnt surface is cleaned off.

It seems once it left the factory, it was covered in a blue plastic shielding material which I assume was removed prior to the silver mylar or film application. What appears "shiny gold" after splashdown are scorched pieces of that silver film. Most the rest then appears to be a dull rust color of the actual metal surface.

Do you think we could put together a photographic sequence of the CM appearance from factory to splashdown?