DU Aviation Experts: I have a couple of questions.

[Savannahmann]

65. I am not a Pilot, nor an expert. But I have some experience in the field.

The Radar would show the transponders altitude information, if that was selected as an option on the tower local radar, but not on a scale that would assist them in informing the pilot he was too low. Of course, there is an old school solution, one that isn't used hardly ever anymore. It is called PAR, Precision Approach Radar. With that, a controller uses the radar to manage the glideslope, and course heading of the pilot. It is very accurate, but out of use, it's obviously easier, and cheaper, to use electronic means, like the ILS, Instrument Landing System. With a PAR approach, a controller literally talks the pilot down to about 200 feet above the ground, and if the pilot doesn't see the runway then, bad weather or whatever, a missed approach is called. The controller advises the pilot where he is on the glide path, and course, and issues corrections to get the plane back on the glide path/course. An example, going below glide path, slightly below. Going left of course, slightly left, turn right (new heading at least four degrees from the current one) Then information on how the corrections are working. Slightly below glide path, slightly below. (You're still low, but not getting any lower) Slightly below glide path, coming up slowly. (You're still a little low, but it's getting better) Finally you'll hear. "At decision height" If you can't see the airport go around and try again. By this time, the pilot is normally over the extended lights, and if he can't see the airport now, the weather really sucks.

The GPS approach would alert the pilot that he was low, but not slow, even PAR and ILS would not notify him he was going too slow, that is when the shaker system and planes own systems kick in. Remember the shaker system is the mechanical alarm for the plane going into a stall.

Number 3, yes. The pilot was trying to salvage the approach, but he was doing so from a point too low, and too slow, he should have taken the missed approach much earlier. Asking for one was not the way to go, the published missed approach is always available, and always kept clear. No other aircraft would have been on that path. I don't know what it was for San Francisco, but for the sake of argument, as an example, it would sound something like this. The pilot says executing missed approach. The controller says. "Understand missed approach" Then the controller repeats the missed approach instructions that are published and the standard. "Climb and maintain two thousand feet, fly runway heading, maintain this frequency for further instructions." Once compliance is confirmed. Then the pilot would be directed back into the landing pattern. Usually a turn to get them back into the pattern, followed with an instruction "Contact approach on (frequency)"

The pilot made a mistake, and compounded that mistake by not starting over, by trying to salvage the approach. He was too high, and too fast. He slammed the brakes on by increasing the angle of attack. That's the nose up attitude. Too much, and the plane slows dramatically, and also loses wind across the wings, or lift. Too much lost speed, and the plane no longer wants to fly, but does want to give into gravity. The shaking stick, the controls literally shake in the pilots hands. That's the plane shouting wake up dude, I'm stalling, we're going to fall out of the sky.

The Air France pilots that put the Airbus plane into the middle of the Atlantic ignored the stall warnings, no shaking stick in an A-320, but all sorts of alarms and flashing lights that said Stall. They put the plane in a nose up attitude, high angle of attack, and didn't increase power. The plane literally plummeted down from about 30k feet, and belly flopped into the Atlantic Ocean.