# What colors were used in the Apollo Lunar Module interior, and why?

There are lots of publications and blog posts on the exterior colors of the Apollo Lunar Module (a function of material choices), but I've struggled to find any information on the interior colors and why those colors were chosen.

This is a modern-day photo of the inside of Lunar Module (LM) Serial Number 2. Serial number 1 was used in an unmanned Earth-orbit-only test flight (part of the Apollo 5 mission) and the second one (LM-2) was built for a follow-on test that was deemed unnecessary and never flown.

LM-2 was used for ground testing prior to the first successful Moon-landing mission and later converted for permanent display at the National Air & Space Museum in Washington D.C.

Note the missing Apollo Guidance Computer Display & Keyboard (DSKY) in the lower center console. I wonder what happened to it? Maybe it went to the Computer History Museum?

• I can recall watching an interview that Buzz Aldrin gave many years ago in which he said the inside of the LM was "navy grey". – Fred Aug 19 '18 at 15:12
• @uhoh -- ...says the guy who added a semi-colon! Seriously, nice work and thanks for the edit. =) – DrFriedParts Aug 20 '18 at 9:35
• @DrFriedParts yikes, that was an artifact from an intermediate solution. Thanks! – uhoh Aug 20 '18 at 9:37
• I want to say; because some tech lead thought it would be a calming color and boost productivity. – anon Aug 20 '18 at 13:40
• related on aviation.SE: Why are most cockpits gray? I suspect the colors and reason to be comparable. – Manu H Jul 8 '19 at 11:22

Colors were decided quite early in the design process by a committee, and were chosen to be consistent between the CM and LM:

October 28, 1963. - An LM-CM displays and controls commonality meeting was held at MSC to explore areas in which commonality might be achieved and to provide a plan of action. Areas discussed included principles of layout, switch and nomenclature conventions, and common specifications -- both functional and environmental. [...] Signal lights, colors, and extinguishment techniques were agreed upon.

Apollo Experience Report: Crew Station Design and Development, NASA Tech Note D-8178

Since the Mercury program, astronauts have had the most say in the design of spacecraft cabins. (They are the ones who have to live and work there.) It's therefore likely that there were astronauts on this committee. As all of the astronauts were pilots, they would probably have picked the aircraft colors that they were used to. And the LM contractor (Grumman) likely already had those colors on hand and happily obliged.

Specific colors are as follows:

• Even though the control panels and floor of the LM were made of aluminum, there were problems with stress corrosion, and thus they were painted. According to NASA Tech Note D-7290, p. 4, the control panels were painted in gray 36231. These paint numbers are from Federal Standard 595, used from 1956 to 2017.

• D-7290 also describes the colors of all switches, controls, indicators, and displays in its Table I. It is too lengthy to include here. Many of the colors are "aviation" colors such as aviation red, aviation yellow, etc.

• The ceiling originally had exposed cabling. When astronauts raised concerns about damaging the cabling, a perforated glass-reinforced plastic ceiling cover was added, in its natural off-white color.

• The handrails are their natural material color.

• Those orange handrails are their natural color? What are they made of? How about the one in the center that changes from orange to black - does its material change? – Organic Marble Sep 23 '19 at 13:39

After the apollo 1 fire, NASA overhauled the entire spacecraft to make sure No flammable or potentially for flame starting could occur. Since alot of the interior is aluminum a metal that can burn in certain conditions, NASA chose to paint the interior metal panels or substitute non-flammable fabrics onboard. So the colors were Gray, and whatever natural colors occured with the manufactured materials

• Do you have any references to back up your assertions? – Organic Marble May 28 '20 at 11:46