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View Full Version : 777 crash at SFO somewhat analyzed by a Jet Airplane pilot



Robert A Whit
07-07-2013, 04:03 PM
I have mentioned Al in the past who as I am is a pilot. Al also has a lot of time on Ships and once owned a yacht. Al knows a lot about flying. I know so little about a Yacht that I expect he is the expert.

His son wrote this report and Al sent it to me.

Al suggested to me that the aircraft altimeter showed the plane to the water level and Al says he thinks it was low tide. I plan to check on Tides at that time at the airport since it abuts the SF Bay.

Some of you may find something out by this Jet pilots remarks. This is by Dick

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Sent: 7/7/2013 7:14:18 A.M. Pacific Standard Time
Subj: Re: 777 crash at SFO


Well I think the first thing we must all do is back away from the hype of the media. Yes a crash happened, but speculating now is just that, speculation. Several things are obvious, one the plane was apparently too low, second during that phase of the approach we have a process called Crew Resource Management or CRM. This calls for all information to be shared with the entire cockpit flight crew, part of that is to have what are called Standard Operating Procedures. To that end from my stand point as a trainer the calls that the nfp or Non Flying Pilot make are just as you outlined Dad, altitude every 10 feet below 200 feet and airspeed plus sink rate.



First of all, from my recollection, Korean Air Lines had some issues years ago, they bought in mostly fighter pilots as Captains, second there is a very strong history in the orient that the Captain is God, no matter what. I had a prime example of it when teaching in the Lear jet in Tuscon, an oriental First Officer, literally flew the simulator into the ground on the orders of the Captain. I'm not saying that was the case here, but there is a history of this activity.


The other thing would be that I would want the airplane into a landing configuration by minimum of 1000 feet agl. That way all one has to is set the landing attitude up and use power to set airspeed. Airspeed is referred to as Vref or Velocity reference airspeed which is 1.3 times the stall speed or 30% above stall, along with half the steady wind speed and all the gust factor.


With respect to runway length, I don't think that was a factor, the 28L runway at SFO is 11,381 feet long and yes there is some of the runway built on fill out into the Bay. Typically we try for the rectangular boxes which are the points we air for, typically the first 25% of the runway.


Also when making a visual approach, and I am going out on a bit of a limb here, but guessing that the weather was clear, he was probably cleared for a visual approach. I typically try to use the VASI or the Visual Approach Slope Indicator and or the Glide slope of the ILS (Instrument Landing System) The normal approach profile is 3 degrees. TheILS consists of two main components, first is the localizer of which the transmitter is set at the far end of the runway and gives left right course information. Second is the glide slope shack and consists of a 390 to 400 MHz signal that is channeled to consistent frequencies of the localizer and is typically set off the side of the runway at the aiming point consisting of the rectangular boxes painted on the runway or the first 25% aiming point.


Also the airplane has to be configured with the gear down leading edge slats deployed (better lift) and flaps down for a high drag configuration. Engine power is typically set at 60 to 70 per cent, since idle to full power in a jet engine can take 5 to 7 seconds.


If I had to take a WAG (wild ass guess) I would say that the plane was making a steep approach and did not configure in time and or was too slow on the configuration change for landing and the resultant spool up time on the engine.


But again the best thing is to wait for the NTSB report. Which by the way you can find online. Most of these are part of the public record.


Dick