Max Launch Abort System

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The Max Launch Abort System (MLAS) is a proposed alternative to the Max Faget-invented "tractor" Launch Escape System (LES) currently planned for use by NASA for its Orion spacecraft in the event an Ares I malfunction during launch requires an immediate abort.

Designed by NASA engineers and reported on the NASA Space Flight webpage on December 6, 2007, the proposed MLAS uses existing ATK-built solid-rocket motors placed, at 90° intervals, in a bullet-shaped boost protective cover originally designed to protect the Orion spacecraft from aerodynamic stresses during launch, along with providing an interface between the spacecraft's crew module with the LES. With the MLAS, NASA can not only reduce the height of the Orion/Ares I stack, but also reduce weight and center-of-gravity issues that a traditional LES would have incurred (something that NASA has been criticized about), and would allow the agency to possibly add more fuel reserves to the Ares I rocket. The bullet-shaped MLAS would also provide better aerodynamic qualities during the first two minutes of flight, reducing stresses when the vehicle encounters the so-called "Max Q" regions of hypersonic flight, along with simplifying production, as existing hardware would be employed. There are several drawbacks. First, the bullet-shaped protective cover would have to be modified and reinforced to allow for the use of the solid-rocket motors, something not needed with the LES, which bolts atop of the LIDS docking ring assembly. Second, the necessity to fire multiple motors (LES uses one motor and multiple nozzles) simultaneously for an abort decreases the theoretical reliability of the launch abort system by introducing more failure modes.

Like the existing LES, the MLAS would provide protection to the Orion spacecraft crew during the first 2½ minutes of flight, with the MLAS being jettisoned, along with the service module's fairing panels, after the solid-rocket first stage is jettisoned. If implemented, the Orion/Ares I stack would resemble the towerless Gemini-Titan stack used between 1965-66, in which ejection seats were used as the primary form of escape for the astronauts who flew on the 10 Gemini missions.