| Pressure | 3.7 psi / 25.5 kPa |
| Suit mass (1g) | 22 lb |
| Life support (primary) | Vehicle provided |
| Life support (backup) | Vehicle provided |
| EVA duration | N/A |
| Program | Mercury |
| Agency | NASA |
| Manufacturer | B.F. Goodrich |
| First use | 1961 |
| Status | Retired |
| Donning / entry | Front entry, custom fitted |
Tight low-volume suit, moving-with-head helmet restraint
Launch / entry contingency pressure retention
No neck bearing; limited head rotation when pressurized; flotation deficiency exposed after hatch jettison incident
"Even a simple IVA suit needs water survival and cockpit visibility contingencies"
Relevant to ultra-light commercial IVA design and crew rescue packaging
Suit lacked adequate flotation during premature hatch jettison water egress
→ Abort-survival packaging must be tested against actual post-egress scenarios, not assumed from lab conditions
Water entered Luca Parmitano's helmet during EVA — vision impaired, comms degraded, breathing compromised
→ Cooling-water management is a primary safety-critical function, not a nuisance issue. Contamination tolerance must be designed in from day one
"Established B.F. Goodrich as the lead US full-pressure suit contractor before Mercury existed"
"Parallel development track alongside Model O testing different mobility solutions"
"Naval and NASA pressure suit research tracks cross-pollinated significantly in this era"
