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Hi Bill - On the 1500-foot marker rule, that works When you have an 11,000-foot runway, but when you're flying a large Boeing 747 or a 777 and you're on the glide slope to land at an airport like St. Marteen's Princes Juliana Intl., which I believe has a runway that's only about a little over 7,000 feet long, the 1500-foot marker rule does not apply, as this image shows.
Hello Mike, a 7000 foot runway is no problem for a 747. I notice that I wrote 1500 feet is the target point. That was a typo. 1000 feet is the target point, and landing between the 500 and 1500 foot marker is the goal. The touch down zone is 3000 feet, and the aircraft must be landed within that area, or a go around should be executed. (That was our procedure. While you could safely stop on most runways if you landed at 4000 feet, if a brake malfunctioned after landing and you couldn't stop, then you could be cited by the company for landing long.)
The white arrows point to a horizontal white line followed by 12 vertical hash marks. The white line is the beginning of the runway, and one should never touch down before that point.
The next group of hash marks (6) 3 on each side of the center line is the 500 foot marker
The next marker is the 2 large squares, one on either side of center line. That is the 1000 foot marker, the target point.
Each group is spaced 500 feet apart, the next two groups have 2 hash marks on either side, and the following two groups have 1 hash mark on either side. The last mark is the 3000 foot marker.
The 747 in the photo appears to be going to touch down prior to reaching the beginning of the runway. He is flaring, but his main gear is about 500 feet from the beginning of the runway. At any rate, it was not safe being that low at that point. There was no reason for him to be that low. If he was trying to give the people on the beach a thrill, it was a poor judgement call.
...And it is absolutely unacceptable for the ILS in a major International airport to be down for an extended period of time, as is apparently the case at SFO.
A shame that trusting innocents had to die to raise the question of what the hell were they thinking?
The FAA mandated the change at SFO, and changes at other airports, in order to improve aviation safety. It's part of a large improvement program. They were moving the end of the runway from 300 feet to 600 feet from the sea wall. Some experts believe that had the change not been made, that the airplane may have hit the sea wall at a different angle creating a greater catastrophe.
It takes time to make those runway changes, and while they're being made, it is necessary to shut the ILS down. An approach in visual condition should be able to be made without the use of any landing aids, such as VASI, ILS.
Once again, there are many factors that could have entered into the equation to cause this accident; we do not know what was going on in the cockpit, the instrument settings, nor do we know why.
Here is an article that talks about the runway changes that are being made.
Non-pilots can jump the gun and call these pilots incompetent, but the professional pilots know all too well that in most aircraft accidents, there are usually multiple factors that contribute to the accidents.
How frequently do such accidents happen? Very infrequently indeed. This is the first one I recall hearing about involving a commercial airliner. If others did happen its been years ago. Among airliners flown by airlines here in the United States, I don't recall hearing of an accident that took place because the air speed upon landing was too slow.
Unless there is some undisclosed mechanical problem that we don't know about this accident clearly involves pilot error. I'll go beyond that. For a flight crew to make such an error upon landing does show incompetence. I strongly question the decision to allow the inexperienced pilot to land at an airport like SFO which involves a challenging runway situation like this one.
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Fortunately, we have an NTSB and trained professional accident investigators who, today, take the time to investigate every aspect of an accident to determine the cause, and all contributing factors, and make recommendations to prevent future accidents of the same type.
Agreed. I'm grateful for NTSB and I believe they are one of the better government agencies. I fly regularly and one of the reasons I feel so secure is knowing that we have both a regulatory system and legal system that will not allow any such accident to occur without the most thorough investigation and consequences when the truth is discovered.
Location: About 10 miles north of Pittsburgh International
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Originally Posted by CrownVic95
The accident that happened proves does anything but prove otherwise. What it proves beyond any debate is my point that it is absolutely unacceptable for the ILS to be down by design at a busy major International airport. Didn't take long to see the result.
The ILS is critical for safety....as proven by the accident....but apparently there is a mindset out there that confuses a 777 pilot with John Wayne flying a DC-3 by the seat of his pants.
By your logic, we should require airline pilots to land without flaps on one day each week to make sure they can handle a flaps failure scenario. After all, flaps are a crutch.
One of the reasons commercial aviation has such an enviable safety record is the redundancy--backups that are backups to the backups.
Are you suggesting that we've lost the redundancy of aircrews that are capable of safely conducting a visual approach in good weather?
One of the reasons commercial aviation has such an enviable safety record is the redundancy--backups that are backups to the backups.
Are you suggesting that we've lost the redundancy of aircrews that are capable of safely conducting a visual approach in good weather?
Well, apparently we did in this case, did we not?
No, I'm not saying that we don't need for pilots to be capable of a manual landing approach and we certainly need redundancy, as you suggest. But it should be just that - redundancy. The all-manual visual approach should not be the only option for heavy jet pilots at a major airport, as it was here. For, in that event, we have lost our redundancy, haven't we?
We have the capability to remove very nearly all of the chance for pilot error in the most safety critical portion of commercial aviation, so we should be taking full advantage of that and never have a planned long-term absence of that redundancy and significant safety cushion.
The old-timers resistant to this progress will still have plenty of opportunity to be cowboys on their days off in private aircraft.
...Unless there is some undisclosed mechanical problem that we don't know about this accident clearly involves pilot error. I'll go beyond that. For a flight crew to make such an error upon landing does show incompetence. I strongly question the decision to allow the inexperienced pilot to land at an airport like SFO which involves a challenging runway situation like this one...
Actually the pilots had thousands of hours of experience in large jet aircraft, and a lot of experience flying into SFO on the 747.
I was based in SFO for 20 years and flew 707, 747, and the A300 out of there. Every airport is slightly different, but landing on runways 28L or 28R is not a difficult approach, and does not require special training. Landing on runway 13 at Kai Tac airport in Hong Kong (now closed), is difficult. Compared to that, SFO is a walk in the park.
Naturally the approach to runways 28 is over water, and there are hills to the west that can create changing winds, but those are things that every pilot learns to expect at any airport, and that they are capable of handling. One can say that flying into SFO is "challenging" because of the water and the hills, but it is a challenge that every commercial pilot can handle because of their experience with similar conditions at many other airports around the world.
The question is still WHY the aircraft got low and slow without early corrections, since there were three pilots in the cockpit.
What were they seeing outside?
What were their instruments indicating?
Was the actual weight of the aircraft heavier than they computed for their approach speeds, causing the wrong approach speed to be computed?
Were there instrument failures?
We don't know those answers, nor do we know the many other factors that may have contributed to the accident. That's why the experts know they can't call something pilot error until all of the data has been discovered and analyzed.
Pilot error has not been ruled out, but it has also not been determined as a cause. Anyone can make idle conjecture and speculate, but it is the experts at the NTSB who will determine the cause of the accident.
it is absolutely unacceptable for the ILS to be down by design at a busy major International airport. Didn't take long to see the result.
The ILS is critical for safety
Not every runway has an ILS. Even at major airports, not every runway has an ILS. There are several other types of instrument approaches. Some rely on technology from the 1930s, I believe (NDB Approaches). Some runways don't even have an instrument approach.
I agree that an ILS is a great aid. About 20 years ago there was a push to implement MLS (Microwave Landing Systems). Supposedly they were going to replace all other instrument approaches and be capable of accommodating all runways.
Not every runway has an ILS. Even at major airports, not every runway has an ILS. There are several other types of instrument approaches. Some rely on technology from the 1930s, I believe (NDB Approaches). Some runways don't even have an instrument approach.
I agree that an ILS is a great aid. About 20 years ago there was a push to implement MLS (Microwave Landing Systems). Supposedly they were going to replace all other instrument approaches and be capable of accommodating all runways.
There are a few MLS units in use throughout the US. I think the shuttle used a MLS system for it's guidance back to landing. If memory serves me correct, the MLS was abandoned because of high costs, and limited benefit over ILS approaches.
At the airline we actually had a rule that we were REQUIRED to fly an approach (other than a visual) into any airport where the control tower was closed...this was to prevent accidental landings at the wrong airport, which had happened on at least one occasion. At night, it was common to build a "Self-Contained Approach" for reference only. It wouldn't get you to the touch down zone, but would give you a general glideslope to use in the approach. We would select the designated runway in the FMS, then build a waypoint on the reciprocal course to the runway hdg, add a point 5 miles out, with an altitude of 1500 ft (AGL). We would then add a 3° glide slope to the equation, and arm the "approach". The sensitivity would never equal that of a properly built GPS approach, but it would give the pilots a "glideslope" reference, and general guidance towards the runway to assist in the visual approach. This proved very helpful at night in "black hole" airports, where the airport had no surrounding lights to provide the pilots with a visual reference.
There are a few MLS units in use throughout the US. I think the shuttle used a MLS system for it's guidance back to landing. If memory serves me correct, the MLS was abandoned because of high costs, and limited benefit over ILS approaches.
At the airline we actually had a rule that we were REQUIRED to fly an approach (other than a visual) into any airport where the control tower was closed...this was to prevent accidental landings at the wrong airport, which had happened on at least one occasion. At night, it was common to build a "Self-Contained Approach" for reference only. It wouldn't get you to the touch down zone, but would give you a general glideslope to use in the approach. We would select the designated runway in the FMS, then build a waypoint on the reciprocal course to the runway hdg, add a point 5 miles out, with an altitude of 1500 ft (AGL). We would then add a 3° glide slope to the equation, and arm the "approach". The sensitivity would never equal that of a properly built GPS approach, but it would give the pilots a "glideslope" reference, and general guidance towards the runway to assist in the visual approach. This proved very helpful at night in "black hole" airports, where the airport had no surrounding lights to provide the pilots with a visual reference.
That's a good idea. In the Airbus 320 series, all runways without an instrument approach have a visual approach with glideslope in the FMS database. VMC use only, of course.
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