COTS benefits cited in Comanche`s shift to Pentium
By John Keller
PHILADELPHIA - The need to reduce electronics costs, secure a reliable long-term supplier, and ensure easy upgrades for years to come were the driving forces in the decision at Boeing Defense and Space Group to switch to the Intel Pentium P5 microprocessor for the RAH-66 Comanche scout/attack helicopter.
From six years ago when the U.S. Army awarded the Comanche contract to a team of Boeing Helicopters in Philadelphia and United Technologies Sikorsky Aircraft in Stratford, Conn., until just last fall, Comanche designers planned on using the Intel 80960 microprocessor for the scout/attack helicopter`s flight computers.
"Last year we starting thinking about switching," explains Eric Stuberude, Comanche requirements manager at Boeing. "The Intel military products [business] is going out of business; you could see that coming. We also wanted to apply commercial practices to the program to save some money."
The i960 and the Pentium are both 32-bit microprocessors, yet the i960 originally specified for the Comanche runs at 25 MHz, while the Pentium runs at 133 MHz. "Clearly you now have a much faster processor," Stuberude says.
Boeing is responsible for the Comanche`s mission avionics package, while Sikorsky is handling major airframe design issues.
"We had done a risk-reduction study and determined we could use a commercial chip," Stuberude says. "We wanted to get into the side of the business that is growing very rapidly - the commercial side. Clearly that is where the money is and where the research and development goes. The P5 chip lets us grow that computer in the longer run with the commercial R&D. We have a built-in upgrade path through the P6 and beyond."
Stuberude says he and his colleagues at Boeing deliberated long and hard over switching to the 133 MHz Pentium that is the latest choice for Comanche computers. "We did an exhaustive trade study," which involved the PowerPC and other commercially developed microprocessors, he says. "It was very close, but the decision went to Intel. It was based on cost and performance benefits."
Substantial benefits in cost and performance drove Boeing avionics designers to shift computers on the RAH-66 Comanche scout/attack helicopter from the Intel i960 microprocessor to the Intel Pentium P5.