> 747s use laser gyros. A few weeks ago on a flight from > Johannesburg to Miami > the pilot explained that "laser radiation" can interfere > with the gyros and > in one case, shut down three engines by switching off the > fuel pumps. I > know these guys away from the "office" and I don't suspect > it was bs. Ummm, how can I put this? Are they on 'ludes?!!! I work as a designer of simulations for aerospace systems. We have intimate knowledge of how aircraft systems are integrated - we have to, we basically re-create the aircraft as computer code. Personally, I've worked on a 747-400, and most recently an A320. This just can't happen. Laser ring gyros are self contained units. There is no way the laser radiation from a (very broken!) MD or CD player could get to them in the avionics bay under the business/first class section on the main level. The laser light would have to get out of the MD/CD player, pass through the floor, pass through the gyro box, and pass through the internal sealed portion of the laser ring part of the gyro. If the laser can get through all of that, you were dead a long time ago. Anyway, laser ring gyros are extremely robust units that rarely fail, and tend to just shutdown like any piece of failed electronic equipment. They certainly won't take out an entire fuel system going down. Cd players can put out RF interference. RF interference can affect any piece of equipment, but if your CD player puts out enough RF to take out a non-RF transmission/reception device (like a laser gyro), then you should be worried about what the heck its doing to you! There is no way the fuel pumps are controlled by whether or not the aircraft knows where it is. The only fuel pumps controlled in even remotely such a manner would be the center tank (and possibly tail tanks) fuel pumps, which are usually auto-shutoff during takeoff and landing to avoid single source contamination issues. This is determined by flap/slat position and weight-on-wheels conditions. Maybe these guys believe the story, but there's no way a laser gyro failure could do that. All the best, Steve (back to deep lurk mode) ----------------------------------------------------------------- To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
