Apollo 17 CDR Eugene Cernan during EVA practice. Note red Commander’s stripe down center of helmet
The Lunar Extravehicular Visor Assembly (LEVA) was designed to fit over the Apollo Pressure Helmet Assembly (aka Bubble Helmet), and latch into place. The LEVA provided “visual, thermal, and mechanical protection to the crewman’s helmet and head.” The LEVA was an elegant design, consisting in one assembly of a thermal cover, 2 visors, and 3 eyeshades. The 2 visors were layered over each other. The inner “protective visor” was made of ultraviolet-stabilized polycarbonate plastic and filtered ultraviolet rays, rejected infrared and, in combination with the sun visor and pressure helmet, formed an effective thermal barrier. The outer “sun visor” was made of high-temperature polysulfone plastic and filtered visible light and most ultraviolet and infrared rays.
The LEVA, like the EMU and most Apollo hardware, went through a few evolutionary steps. The first LEVAs worn on the moon on Apollo 11 featured the basic LEVA with side visors only. Apollo 12 added the center eyeshade with viewport door. Apollo’s 13 – 17 LEVAs featured side and center eyeshades, as well as a hard shell cover over the thermal cover on top of the LEVA. The hard shell covering the LEVA ws added after it was discovered that micrometeoroids were penetrating the thermal covering of the LEVA. The commander’s LEVA sported the red CDR stripe down the center from Apollo 13 on. Also of note, on Apollos 15 – 17 the surface crewmen wore the PLSS Tool Carrier Harness on their backpacks. In order to facilitate dropping the harness off the PLSS to reenter the LM quickly in the event of an emergency, a pair of straps was attached with velcro to each side of the LEVA. Click on photo below to see the straps. Photo above and at top of page courtesy Kipp Teague’s Project Apollo Archive
NASA LEVA diagram Detailed diagram showing all the major parts of the early LEVA
Front view. Note tabs to pull down the various visors and eye shades. Also note image of a smiling Paul Kashuk reflected in the visor! | Side view, with side eyeshades pulled down | Great photo! Note that Paul put tape measures in the photo. Inside of helmet is red and the cowling flaps on the bottom of the LEVA are shown. Note the open latch on the front. | Side view. Every seam on the thermal cover is visible. |
Front view showing the hinge mechanismLatch mechanism and EMU helmet ringInside-the-helmet view of the hinge mechanism |