...the infrastructure needed to maintain all that computing across decades becomes significant.
"With IMA you take all the complexity from all those different functions and house them in one computer.
"It operates on a single computer as if it were multiple virtual computers that cannot interfere with each other... [and] you can add computing resources as necessary to cover additional workloads."
The amount of computing power and memory that can be dedicated to each task is also set before the mission so there is no danger of one task swallowing up processor cycles that are needed by a vital onboard system.
While Orion's processing power outstrips that of the Shuttle's systems, Honeywell's Smithgall said computing muscle has taken a back seat to reliability when designing the Orion's computing systems.
"Imagine that your life was on the line every time your PC hung up and displayed the blue screen," he said.
"The real innovation with this type of computer is not its performance but its guarantees against ever doing anything unexpected or incorrect."
This reliability is made even more remarkable considering the harsh environment in which Orion's systems will operate - temperatures in space fluctuate between extreme cold and heat, and the spacecraft will be bombarded by high-energy cosmic and solar radiation.
"Spaceflight has vibration and radiation exposures that are quite unlike anything a commercial aircraft ever sees," Smithgall said.
"We end up with the performance level of a desktop computer of about five years ago but with extremely high reliability, low power consumption and which is survivable in adverse environments."
Orion's computer systems have been designed to deal with the uniquely hostile environment of space: "You take a commercial chip and you test it and find out how it is going to fail. For instance, is it going to burn out or flip a bit? And then you design circuitry and software around it to mitigate the effects," Nasa's Lemke said.
On top of the inherent stability of the hardware design, Orion carries...