F-22 Becomes a Reality

[MultimediaMan]

Aerospace development and Computer development are amazingly far apart.

Hell, even top-line jets fighters (up until the F22) used a 9600 bps SERIAL interface for their systems bus. F15 Eagles still use Vacuum Tubes for their missile targeting radar.

Time and development costs are relative: using "all of the experience and lessons learned from previous projects" runs up budgets - big time. Many of the lessons learned were expensive because of a single failure, true; but some of those lessons opened up huge cans of worms as far as what needed to be done to avoid a repeat in the future.

People forget that the bulk of the useful knowledge gleaned from project to production is stored in bags of warm meat that often leave the developing company, retire or die without writing all of their documentation down.

[Marshmallowman]

Another thing, I would think the components they are using would be radiation/emf hardened...probably good reason to use are larger process for making the chips.

Vacuum tubes are inherently less suseptible to emf, so they are probably in no hurry to upgtrade that stuff either.

[GT98]

Originally posted by Marshmallowman
Properly designed embedded systems don't need excessive power,just enough to get the job done efficiently and reliably...if an 8086 does the job its good enough,that does not explain the crash every hour or 2....
.

Could be just bad programing. THere was a crash of a Yf-22 prototype that was cause by software. The pliot survived and the plane was pretty much intact.

[MultimediaMan]

Yeah, that was a long time ago...it happened during high AoA testing...the thing basically fell on the runway, it had to be completely rebuilt.