Crew Exploration Vehicle Environmental Control and Life Support Fire Protection Approach

Abstract

As part of preparing for the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) worked on developing the requirements to manage the fire risk. The new CEV poses unique challenges to current fire protection systems. The size and configuration of the vehicle resembles the Apollo capsule instead of the current Space Shuttle or the International Space Station. The smaller free air volume and fully cold plated avionic bays of the CEV requires a different approach in fire protection than the ones currently utilized. The fire protection approach discussed in this paper incorporates historical lessons learned and fire detection and suppression system design philosophy spanning from Apollo to the International Space Station. Working with NASA fire and materials experts, this approach outlines the best requirements for both the closed out area of the vehicle, such as the avionics bay, and the crew cabin area to address the unique challenges due to the size and configuration of the CEV.

Evaluating Material Flammability in Microgravity and Martian Gravity Compared to the NASA Standard Normal Gravity Test

“…One of the major lessons learned from the Apollo 1 fire is that it is impossible to eliminate all ignition sources, 6 so fire prevention is achieved in spacecraft through material controls near potential ignition sources and the use of fire resistant materials. After Skylab, the Space Shuttle and the International Space Station (ISS) have operated at normal sea-level conditions (air, 21% oxygen and 79% nitrogen by volume at 14.7 psia total pressure) except for brief pre-EVA activities when oxygen levels are increased for a short period of time to 30% oxygen while the total C https://ntrs.nasa.gov/search.jsp?R=20130010991 2018-05-09T17:38:31+00:00Z pressure is lowered to 10.2 psia.…”