Comparing Alan Eustace’s Spacesuit with Neil Armstrong’s

Posted on Fri, November 27, 2015
  • by: Lisa Young is an objects conservator for the National Air and Space Museum

Our conservation team had the pleasure of hosting Alan Eustace, former Google executive, engineer, and stratospheric explorer, this month in the Emil Buehler Conservation Laboratory. Eustace and his StratEx team are well known for their three world records including one for the highest altitude jump at 41,422 meters (135,899 feet) in 2014. The adventurer was in town giving a lecture about his historic jump and to donate to the Museum the suit, life support, and balloon equipment module he used during the jump.

This visit was especially exciting for our team as we are busily working on our project to preserve Neil Armstrong’s spacesuit. It was a pleasure to talk to Eustace about his historic jump and to see the one-of-a-kind spacesuit he wore to the outer edges of the atmosphere. We couldn’t help but compare the materials, technology, and engineering of his suit to the spacesuit created for Neil Armstrong 45 years ago. It was amazing to see what has changed and what hasn’t.

<p>Alan Eustace, who holds the record for highest altitude jump, visited our Conservation Labratory in November 2015. </p>


ILC Dover, formerly the International Latex Company, made both suits, and they are remarkably similar. The suits share the same primary function, to keep the wearer alive long enough to complete their mission and return safely to Earth. Both suits did this very well.

Eustace’s suit resembles those worn by Shuttle astronauts and utilizes modern materials that were not available in the 1960s. However, both suits do share a similar protective outer covering, or Thermal Micrometeoroid Garment (TMG). The TMG is used to keep its wearer safe from extreme temperature differences, radiation, and particles in space. Each TMG consists of more than 20 layers of fabric. Many of those materials have remained the same since Apollo. These include protective materials such as aluminized Mylar, Dacron, and Kapton.

The interior restraint layer of each suit is also similar in function, although different types of engineering hardware and material updates were used to make Eustace’s suit. The main function of the restraint system was to make sure its wearer (pilot or astronaut) could remain in position, have flexibility and mobility, and be able to complete tasks while under pressure. While Eustace’s restraint layer had several modern updates, both suits used the traditional cable and pulley systems including anodized aluminum alloy hardware with the similar connectors and locks. These locking mechanisms are also found on the helmet and gloves that attach them to the suits. Eustace did comment, however, that he had to adapt his gloves so that he could release his helmet lock with one hand. Eustace also wore a liquid cooling garment under his suit to keep his body temperature cool. This was a system that was adapted for the Gemini program, but primarily used in Apollo and has been in use ever since.

Alan Eustance breaks Felix Baumgartner's record for highest altitude jump. 


The biggest difference between the suits is the materials that were used to create the pressure bladder. Early Apollo suits used a combination of natural and synthetic rubber to form the pressure bladder. The system was state of the art at the time but was not meant to last long term. The rubber is one of our biggest challenges to preserving Armstrong’s spacesuit—its intended working life was only meant to be six months. With the evolution of materials following Apollo 14, engineers at ILC were able to add an antioxidant to the rubber formula that helped to expand the lifetime of the rubber components on future suits. Much like current extravehicular activity (EVA) suits worn on the International Space Station (ISS), Eustace’s suit has a polyurethane pressure bladder. This material has better aging properties, is readily available, is thinner, and more widely manufactured. It can also be changed out quickly if the suit needs to be repaired on the ISS. Although we do see degradation of the rubber used in Apollo spacesuits, it was the best material available at the time and it did its job very well by enabling astronauts to work and live on the lunar surface.

Having an opportunity to compare and contrast suits made 45 years apart was very exciting for our team. Hearing about Eustace’s experience making the jump, of course, was also fantastic. The research we are conducting now on spacesuits and how best to preserve, store, and display them will help ensure the long-term preservation of Eustace’s more modern suit along with our Apollo spacesuits.