The current MK-III carbon-graphite/epoxy Hard Upper Torso (HUT)/hatch assembly represented an 8.3 psi (≈57 kPa) technology demonstrator model of a zero pre-breathe suit. In this configuration, the MK-III suit weighed about 120 lb (≈54 kg). Since future lunar/planetary suits will need to operate under the influence of gravity, as well as operate at 4.3 psi (≈30 kPa), the weight of the suit had to be reduced to a minimum of 79 lb (≈36 kg) with the incorporation of lightweight structural materials and slight HUT/hatch assembly geometric redesign.

The lightweight HUT/hatch assembly will interface directly with current MK-III hardware. Current material developments have allowed many industries to push the envelope of weight reduction. Many robust, lightweight structures based on the technologies of advanced honeycomb materials and new composite laminates lend themselves well to applications requiring materials that are both light and strong.

These advanced materials will be used to design and fabricate a hard upper torso shell structure with rear-entry closure and corresponding hatch. The lightweight HUT/hatch assembly will retrofit with existing MK-III hardware elements, and will contribute to comparative analysis by the customer. By fabricating a lightweight HUT, NASA will have immediate plug-and-play capability and will facilitate comparability with current hardware.

This work was done by Michael McCarthy of Air-Lock, Inc. for Johnson Space Center. MSC-24391-1