Airport landing system off when plane crashed in San Francisco

Reuters ^ | July 07, 2013 | Peter Henderson and Dan Levine

[george76]

A navigation system that helps pilots make safe descents was turned off at San Francisco airport on Saturday when a South Korean airliner crashed and burned after undershooting the runway ...

The system, called Glide Path, is meant to help planes land in bad weather. It was clear and sunny, with light winds, when Asiana

...

San Francisco International has turned off the system for nearly the entire summer on the runway where the Asiana flight crashed, according to a notice from the airport on the Federal Aviation Administration's Web site

[BunnySlippers]

This is supposedly not unusual. It was off for the summer. Apparently common.

Couldn’t the pilots land w/o it?

[calex59]

So, what does this have to do with anything? If it was clear weather the pilot didn’t need the system or was he totally incompetent?

[a fool in paradise]

San Francisco International has turned off the system for nearly the entire summer

Repairs?

Electricity usage "brownout" to conserve energy for air conditioning around the region?

[oh8eleven]

A navigation system that helps pilots make safe descents was turned off at San Francisco airport
C'mon, real men don't need navigation safety systems.

[Vendome]

ILS doesn’t matter on a bright clear day with light winds.

These planes are equipped with their own various radars. In particular to squaker that goes off and calling your feet from the ground.

I am curious what happened here though.

[wastedyears]

Why the hell would the ILS be off?

[Stosh]

Has anybody blamed this on the sequester yet?

[mandaladon]

Just as a matter of curiosity why would two big holes be burned in the top of the fuselage ? Seems that’s where carry-on luggage would be secured in the overheads.

[Vendome]

[dalereed]

“The system, called Glide Path”

No it’s not!!!

It’s called ILS, Instrument Landing System.

Totally unnecessary in clear weather.

[justlurking]

At SFO, runway 29L has a 4-light PAPI system on the left side of the runway.

When the aircraft is on the glide path, 2 lights are red, and 2 lights are white. If the aircraft is significantly below the glide path, all 4 lights are red.

[HangnJudge]

Clear weather
Daylight

No excuse

[Vendome]

Dunno.

[justlurking]

It’s called ILS, Instrument Landing System.

That's what I was thinking. I have never heard of "Glide Path".

However, I just looked up the airport info for SFO 29L. It has a 4-light PAPI, or at least it did if the plane didn't slide over it.

[webstersII]

“No it’s not!!!

It’s called ILS, Instrument Landing System.

Totally unnecessary in clear weather.”

That’s not what the article said. “Glide Path is a computerized system based at an airport that calculates a plane’s path of descent and sends it to pilots in real time.”

The ILS is a different system from Glide Path. It is only a set of two radio transmitters and it doesn’t interact with the plane. Besides, if the ILS was off then they wouldn’t be able to make evening and night landings after dark at that airport.

[Vaduz]

Yes but didn’t.

[justlurking]

Just as a matter of curiosity why would two big holes be burned in the top of the fuselage ?

The fire started after the crash, and apparently after everyone was out of the plane. The right engine is sitting next to the fuselage, and probably triggered the fire.

The 777 has a center fuel tank (at least the extended range versions). If it wasn't empty, it would have fueled the fire.

[Yosemitest]

After 30 years of Air Traffic Control experience, most as Tower Watch Supervisor in the USAF, this was a Pilot Error Crash.
The pilot came in too steep, with too much airspeed to bleed off, so he put it into a stall position to get rid of the airspeed.
But he stalled it out and got lucky that he belly landed it into the underrun, and the closed portion of the runway, before the landing threshold and leaving a portion of the tail in the bay.

Both the PAPIs and the Glideslope were NOTAMed off due to the displaced landing threshold.
Had they been on the point of touchdown would have been too short for a safe landing.

But what I'd like to know is the compression rate and control instructions from the air traffic controllers starting with his descent from SF Center, through SF TRACON to the handoff to the tower.
Did the controllers keep him high in altitude and not allow enough of a descent rate due to traffic departing under him (the four-post operation of a busy TRACON)?
And did the controllers keep his speed up with their control instructions, until too short of a final when they handed him off to the tower, and not allow him time to bleed off the airspeed, due to the arrival rate of aircraft they were shoe-stringing down final at that time?