Stabilized Approaches must be part of an Standard Operating Procedure
(SOP) and not just a criteria, policy or even best practice. Procedure
means that it is a written set of steps, notes and it is trained by the
airline, checked by the FAA and continually verified, reviewed and
updated by the FAA and the airline. Part of a stabilized approach
procedure must include a verbalized communication of the aircraft state
and progress at several points in the approach and a verbal command to
continue the approach or to Go Around as the aircraft passes these
points.
One of the most important things we learned in the recent June 18, 2013 Flight Safety Foundation (FSF) Go-Around Safety Conference, sponsored jointly by EuroControl, European Regions Airline Association (ERAA) and the European Advisory Committee and the International Advisory Committee (EAC and IAC) of the FSF, in Brussels, addressed the idea of a criteria, policy or best practice as opposed to an SOP.
[See the conference link at http://www.skybrary.aero/index.php/Portal:Go-Around_Safety]
It is one thing to have a 500ft or even a 1000 ft stabilized approach criteria. It is quite another thing to have an SOP that all flight crew members are trained to that says if the crew does not accomplish a stabilized appraoch by 1000 ft or even 500 ft, the pilot monitoring flight crew member(s) flight crew member(s) not flying, say verbally "GO AROUND, APPROACH UNSTABLE," and then per SOP, the pilot flying (PF) initiates the Go Around (GA)as per trained, per briefed and as published per air traffic management procedures.
Even now, even with a stabilized approach criteria or policy at 500ft or 1000 ft and a even with no fault GA policy, wherein the crews motive for going around is not called into question, air lines still need to have an SOP, a written procedure that says crew members must verbalize, "1000 feet, APPROACH STABLE, CONTINUE," or "1000 feet, APPROACH UNSTABLE, GO AROUND."
Why is this important now? Well, it has always been important. However now we need to understand what happened to Asiana 214 and learn from it. Having seen the video of Asiana 214 approaching San Francisco International (SFO) runway 28 Left, one thing is quite noticeable. The approach appears very flat, meaning very low in altitude at a considerable distance from the stone wall at the waters edge. In lieu of the standard three degree glide slope, the aircraft appears to have essentially leveled off at 100 or 150 feet 1/4 to 1/2 mile from the seawall.
Keep in mind that the designated normal landing area on any runway is between 500 feet and 1500 feet down the runway. Add onto that, the stone wall at the waters edge appears to be approximately 1000 feet from the end of the runway. So the aircraft landed approximately 2000 feet short from the intended point of landing, that is, the normal landing area on the runway. This means that the aircraft had descended approximatley 50ft and 100ft below the normal 3 degree glide slope. This deviation did not occur 4 or 7 seconds from landing, but at least 1/2 mile or more from the end of the runway.
If and when the aircraft passed 1000 feet in altitude or even 500 feet during the final approach, which would have been a considerable distance from the runway, the aircraft had to have been well below glide slope. So did the airline have a procedure (SOP) that required the crew to verbalized stable or unstable and continue or go around? If so, why did the crew continue the unstable approach? Did the crew notice the unstable approach?
In addition, early reports from the NTSB identified the airspeed decreased from a landing target of 137 knots to about 109 knots. Remember that normal target speed is 130% of the stall speed at that weight or 1.3 times the stall speed.
Rounding off for argument sake, a stall speed of 100 knots, with a 30% buffer gives a landing speed of 130 knots. The stall warning stick shaker come on 5-8 knots above stall speed (or more correctly stall angle of attack). So the crew was not flying the aircraft just a little slow, the crew was flying substantially slow, dangerously slow and into the region of rapidly rising induced drag. The crew appeared to be unaware of the rapid decay from 137 knots to 109 knots right into the stall. I wonder if the subject of the region of reverse command in swept winged aircraft was part of the Asiana B777 training program?
Remember it is typical for crew to add 5-7 knots to give keep a margin above the minimum target speed. So that would mean most pilots would be flying at about 142 knots. The aircraft landed 30 or more knots slow. This would require a significant increase in angle of attack and nose up position, which was seen in the video at the last moments. This again is a major deviation from a stabilized approach procedure. This deceleration should have been recognized immediately as it occurred initially below 137 knots and corrected by the crew or the crew should have commanded a go around and the GA SOP should have been initiated as soon as the airspeed fell below the target speed. The correction would have been to add substantial power and lower the nose slightly.
As it happened the aircraft was well below glide slope and very slow below landing target speed. Both of these occurred well before the aircraft arrived at the sea wall. Not having a Go Around SOP based on deviation from Stabilized Approach is a severe risk to safety. Not having a training program that covers the aerodynamic principle of the region of rising induced drag and does not address corrections is a severe risk to safety.
Concerning the Instrument Landing System (ILS) electronic glide slope for runway 28 left being inoperative, this puts a burden on the crew members in the cockpit to build an artificial glide slope using runway data. But this would have been a good training opportunity for the crew to build that approach within the aircraft flight management system. This is a standard and written procedure in the B777 flight manual. If that was not done, the runway did have precision approach path indicators known as PAPI, which when below glide slope, would have been illuminating four red lights to the left side of the landing area of the runway.
One last thing, as the initial operating experience instructor pilot sitting in the right seat should have said when things got far out of hand, "Okay, I've got it," and flown the aircraft back into safety.
Alot going on here to discuss. We all would be better off tomorrow if we all tried to understand what happened to Asiana 214 today.
Stabilized Approach Procedures, Go Around Procedures and substitutes for ILS procedures all must be part of the skills sets of B777 crew members.
One of the most important things we learned in the recent June 18, 2013 Flight Safety Foundation (FSF) Go-Around Safety Conference, sponsored jointly by EuroControl, European Regions Airline Association (ERAA) and the European Advisory Committee and the International Advisory Committee (EAC and IAC) of the FSF, in Brussels, addressed the idea of a criteria, policy or best practice as opposed to an SOP.
[See the conference link at http://www.skybrary.aero/index.php/Portal:Go-Around_Safety]
It is one thing to have a 500ft or even a 1000 ft stabilized approach criteria. It is quite another thing to have an SOP that all flight crew members are trained to that says if the crew does not accomplish a stabilized appraoch by 1000 ft or even 500 ft, the pilot monitoring flight crew member(s) flight crew member(s) not flying, say verbally "GO AROUND, APPROACH UNSTABLE," and then per SOP, the pilot flying (PF) initiates the Go Around (GA)as per trained, per briefed and as published per air traffic management procedures.
Even now, even with a stabilized approach criteria or policy at 500ft or 1000 ft and a even with no fault GA policy, wherein the crews motive for going around is not called into question, air lines still need to have an SOP, a written procedure that says crew members must verbalize, "1000 feet, APPROACH STABLE, CONTINUE," or "1000 feet, APPROACH UNSTABLE, GO AROUND."
Why is this important now? Well, it has always been important. However now we need to understand what happened to Asiana 214 and learn from it. Having seen the video of Asiana 214 approaching San Francisco International (SFO) runway 28 Left, one thing is quite noticeable. The approach appears very flat, meaning very low in altitude at a considerable distance from the stone wall at the waters edge. In lieu of the standard three degree glide slope, the aircraft appears to have essentially leveled off at 100 or 150 feet 1/4 to 1/2 mile from the seawall.
Keep in mind that the designated normal landing area on any runway is between 500 feet and 1500 feet down the runway. Add onto that, the stone wall at the waters edge appears to be approximately 1000 feet from the end of the runway. So the aircraft landed approximately 2000 feet short from the intended point of landing, that is, the normal landing area on the runway. This means that the aircraft had descended approximatley 50ft and 100ft below the normal 3 degree glide slope. This deviation did not occur 4 or 7 seconds from landing, but at least 1/2 mile or more from the end of the runway.
If and when the aircraft passed 1000 feet in altitude or even 500 feet during the final approach, which would have been a considerable distance from the runway, the aircraft had to have been well below glide slope. So did the airline have a procedure (SOP) that required the crew to verbalized stable or unstable and continue or go around? If so, why did the crew continue the unstable approach? Did the crew notice the unstable approach?
In addition, early reports from the NTSB identified the airspeed decreased from a landing target of 137 knots to about 109 knots. Remember that normal target speed is 130% of the stall speed at that weight or 1.3 times the stall speed.
Rounding off for argument sake, a stall speed of 100 knots, with a 30% buffer gives a landing speed of 130 knots. The stall warning stick shaker come on 5-8 knots above stall speed (or more correctly stall angle of attack). So the crew was not flying the aircraft just a little slow, the crew was flying substantially slow, dangerously slow and into the region of rapidly rising induced drag. The crew appeared to be unaware of the rapid decay from 137 knots to 109 knots right into the stall. I wonder if the subject of the region of reverse command in swept winged aircraft was part of the Asiana B777 training program?
Remember it is typical for crew to add 5-7 knots to give keep a margin above the minimum target speed. So that would mean most pilots would be flying at about 142 knots. The aircraft landed 30 or more knots slow. This would require a significant increase in angle of attack and nose up position, which was seen in the video at the last moments. This again is a major deviation from a stabilized approach procedure. This deceleration should have been recognized immediately as it occurred initially below 137 knots and corrected by the crew or the crew should have commanded a go around and the GA SOP should have been initiated as soon as the airspeed fell below the target speed. The correction would have been to add substantial power and lower the nose slightly.
As it happened the aircraft was well below glide slope and very slow below landing target speed. Both of these occurred well before the aircraft arrived at the sea wall. Not having a Go Around SOP based on deviation from Stabilized Approach is a severe risk to safety. Not having a training program that covers the aerodynamic principle of the region of rising induced drag and does not address corrections is a severe risk to safety.
Concerning the Instrument Landing System (ILS) electronic glide slope for runway 28 left being inoperative, this puts a burden on the crew members in the cockpit to build an artificial glide slope using runway data. But this would have been a good training opportunity for the crew to build that approach within the aircraft flight management system. This is a standard and written procedure in the B777 flight manual. If that was not done, the runway did have precision approach path indicators known as PAPI, which when below glide slope, would have been illuminating four red lights to the left side of the landing area of the runway.
One last thing, as the initial operating experience instructor pilot sitting in the right seat should have said when things got far out of hand, "Okay, I've got it," and flown the aircraft back into safety.
Alot going on here to discuss. We all would be better off tomorrow if we all tried to understand what happened to Asiana 214 today.
Stabilized Approach Procedures, Go Around Procedures and substitutes for ILS procedures all must be part of the skills sets of B777 crew members.
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