37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Attributes | |
ACN | 906151 |
Time | |
Date | 201008 |
Local Time Of Day | 1801-2400 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Night |
Aircraft 1 | |
Make Model Name | A320 |
Operating Under FAR Part | Part 121 |
Flight Phase | Final Approach |
Component | |
Aircraft Component | Autothrottle/Speed Control |
Person 1 | |
Function | Pilot Flying Captain |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Events | |
Anomaly | Deviation - Procedural Published Material / Policy Inflight Event / Encounter Unstabilized Approach |
Narrative:
While conducting a night; VMC approach utilizing the VOR-DME approach; we received a low energy warning ('speed-speed-speed') at approximately 100 ft AGL which necessitated the use of toga thrust to limit further decay in airspeed and prevent a hard landing. The initial approach was normal and we were vectored to intercept the final while given a descent clearance to 1;600 ft and being asked to maintain our speed (185 KTS) until 5 miles out. Upon receiving the approach clearance; I armed the approach and immediately noted final app annunciated on the FMA. At that point the aircraft began to climb to 2;000 ft to capture the descent path. As pilot flying; it seemed to me that the aircraft didn't start the final descent at the top of descent point so I disengaged the autopilot and autothrust concurrently and started descending toward the PAPI approach path while configuring for landing. I attempted to reach stabilized approach criteria as quickly as possible but at 1000 ft AGL I was target +20 KTS and sinking 1;200 FPM with thrust at idle. At the 500 ft gate I was stable on speed and sink rate (target + 8 KTS; sink 900 FPM); but with the thrust still at idle (I had not re-engaged autothrust). I was maintaining the PAPI glide path to 100 ft when simultaneously the first officer (pilot not flying) and I became aware of our below target airspeed while receiving almost immediately afterwards the low energy warning. I responded by placing the thrust levers at toga to limit any further decay in airspeed and arrest the rate of descent. The resulting touchdown was firm and in the landing zone but otherwise uneventful. Taxi-in and parking was normal.I have endeavored to closely follow SOP's throughout my career and take my responsibilities very seriously. I know the aircraft pilot handbook and fom well and follow their guidelines rigorously and yet failed to conduct the approach described herein properly by neglecting to adhere to some of our most basic principles. In conducting the approach setup for the VOR-DME; I failed to utilize the QRH as an aid believing that I was proficient from having flown numerous VOR approaches in mexico recently. I may have inadvertently failed to clear present position while flying the approach which may have caused the aircraft to climb to 2;000 ft instead of continuing the descent to the FAF altitude in open descent. The aircraft response certainly increased my task loading; but my response in disconnecting the automation removed a barrier that would have prevented the unstabilized approach that resulted. When the aircraft failed to descend at the expected point in the approach; my reaction in disconnecting autothrust was instinctive but ill-advised since as stated; it removed a barrier but also was not pre-briefed and is not authorized at night. Our descent below 1;000 ft AGL while unstable should have resulted in a go around with plenty of time and fuel to conduct another approach. Finally; inadequate monitoring of the flight instruments by the pilot not flying removed the final barrier that would have prevented the decay in airspeed. Very simply; my event should cause all of us to rededicate ourselves to following SOP's and guidelines as published in our manuals. My appreciation for the barriers which serve to prevent bad consequences and outcomes has increased immeasurably. Our job can become so routine that we fail to adequately recognize when an abnormal or non-routine situation has put us 'into the yellow'; and even two well-trained; conscientious and diligent professional pilots can make mistakes. The pilot monitoring has to monitor; even on beautiful clear nights and; most importantly; has to know what to monitor.
Original NASA ASRS Text
Title: A320 Captain reports receiving a Low Energy Warning at 100 FT AGL during a night VMC approach. Autothrust was disengaged when the aircraft did not responded as expected when capturing the VOR DME approach path. TOGA thrust was used to prevent a very hard landing.
Narrative: While conducting a night; VMC approach utilizing the VOR-DME approach; we received a Low Energy Warning ('Speed-Speed-Speed') at approximately 100 FT AGL which necessitated the use of TOGA thrust to limit further decay in airspeed and prevent a hard landing. The initial approach was normal and we were vectored to intercept the final while given a descent clearance to 1;600 FT and being asked to maintain our speed (185 KTS) until 5 miles out. Upon receiving the approach clearance; I armed the approach and immediately noted FINAL APP annunciated on the FMA. At that point the aircraft began to climb to 2;000 FT to capture the descent path. As pilot flying; it seemed to me that the aircraft didn't start the final descent at the top of descent point so I disengaged the autopilot and autothrust concurrently and started descending toward the PAPI approach path while configuring for landing. I attempted to reach stabilized approach criteria as quickly as possible but at 1000 FT AGL I was target +20 KTS and sinking 1;200 FPM with thrust at idle. At the 500 FT gate I was stable on speed and sink rate (target + 8 KTS; sink 900 FPM); but with the thrust still at idle (I had NOT re-engaged autothrust). I was maintaining the PAPI glide path to 100 FT when simultaneously the First Officer (pilot not flying) and I became aware of our below target airspeed while receiving almost immediately afterwards the LOW ENERGY WARNING. I responded by placing the thrust levers at TOGA to limit any further decay in airspeed and arrest the rate of descent. The resulting touchdown was firm and in the landing zone but otherwise uneventful. Taxi-in and parking was normal.I have endeavored to closely follow SOP's throughout my career and take my responsibilities very seriously. I know the aircraft Pilot Handbook and FOM well and follow their guidelines rigorously and yet failed to conduct the approach described herein properly by neglecting to adhere to some of our most basic principles. In conducting the approach setup for the VOR-DME; I failed to utilize the QRH as an aid believing that I was proficient from having flown numerous VOR approaches in Mexico recently. I may have inadvertently failed to clear present position while flying the approach which may have caused the aircraft to climb to 2;000 FT instead of continuing the descent to the FAF altitude in open descent. The aircraft response certainly increased my task loading; but my response in disconnecting the automation removed a barrier that would have prevented the unstabilized approach that resulted. When the aircraft failed to descend at the expected point in the approach; my reaction in disconnecting autothrust was instinctive but ill-advised since as stated; it removed a barrier but also was not pre-briefed and is not authorized at night. Our descent below 1;000 FT AGL while unstable should have resulted in a go around with plenty of time and fuel to conduct another approach. Finally; inadequate monitoring of the flight instruments by the pilot not flying removed the final barrier that would have prevented the decay in airspeed. Very simply; my event should cause all of us to rededicate ourselves to following SOP's and guidelines as published in our manuals. My appreciation for the barriers which serve to prevent bad consequences and outcomes has increased immeasurably. Our job can become so routine that we fail to adequately recognize when an abnormal or non-routine situation has put us 'into the yellow'; and even two well-trained; conscientious and diligent professional pilots can make mistakes. The Pilot Monitoring has to monitor; even on beautiful clear nights and; most importantly; has to know what to monitor.
Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.