Hatchback Suits to Reduce Dust and Lead Time

Two key challenges present themselves for lunar surface activity: dust, and lead time. Peter Kokh's solution is to build the suit like Russian Orlan suits--where the backpack is the entry hatch--and then keep the suits outside. The suit latches into a pressure seal in the side of the habitat so that most of the suit is outside while the back of the backpack stays inside. The airlock is a door that closes over the backpack to seal the habitat.

Image of Russian Orlan suit in underwater training.

Dust is a major problem: it caused hystamine reactions in the Apollo crews, and the fines can easily get into equipment unless elaborate precautions are taken. Further, the dust sticks to the beta cloth used in space suits, and just grinds into the fabric rather than brushing off.

The back of the suit could be made of some material which doesn't get dusty, perhaps by choosing a polished material such as mylar or aluminum, or concievably by using vibrational or electrostatic methods to clear it off. As the back hatch is the only external surface that comes into contact with the habitat interior, little dust will enter the habitat--the dirty boots aren't brought inside.

The second key factor in using a "dockable" suit stems from the impressive weight and cost savings in mounting habitat systems outside of the outpost's pressurized volume. However, if an externally mounted system malfunctions, how quickly that item can be accessed for servicing is an issue.

In general, we want to design the systems so that this isn't a problem. Redundancy and reliability in mission-critical systems alleviates most of the urgency in going outside to fix things.

As long as we have to prebreathe, we're probably going to be somewhere between 2 hours and 6 hours from an unanticipated EVA. If we can solve that problem, then it depends on how quickly we can make a suit ready without unnecessarily compromising safety.

It is in this requirement for reducing maintainence lead time that dockable suits come in handy. While conventional space suits are disassembled and inspected before each use, only with the backpack is this practical for a suit largely stored outside. We're thus forced into elegant design and self-testing suits.

Suits kept in a perpetual state of readiness, of course, have little lead time. As a result, a system outside the outpost can be quickly accessed, and without the expense of hours of crew time.

This depends on how much we can afford to invest in the technology, and how much overhead we can put into keeping the EVA system in a perpetual state of readiness. The hatch back, at least, is already available technology.

Development cost is the snake in the garden, of course, but we might expect folks on the moon to develop these things as time goes on. For the initial exploration missions, we can use current technology.