37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Attributes | |
ACN | 1100656 |
Time | |
Date | 201307 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | LGA.Airport |
State Reference | NY |
Environment | |
Flight Conditions | IMC |
Aircraft 1 | |
Make Model Name | A320 |
Operating Under FAR Part | Part 121 |
Flight Phase | Initial Approach |
Route In Use | Vectors |
Flight Plan | IFR |
Component | |
Aircraft Component | Autothrottle/Speed Control |
Person 1 | |
Function | First Officer Pilot Not Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe Deviation - Altitude Overshoot Deviation - Procedural Published Material / Policy Deviation - Speed All Types Inflight Event / Encounter Weather / Turbulence |
Narrative:
While being vectored for the ILS 22 through moderate weather we turned base; then final; armed the approach and began the descent. We came through the bases of the clouds and it became obvious through multiple lightning strikes; the clouds we were in were very convective which we did not previously know. There were multiple lightning strikes around us and the airspeed began to stagnate. I announced the stagnation and decrease in airspeed to the captain and he responded that he was seeing it to. This was still before the FAF between 3;000 and 2;000 ft. I was busy switching from approach to tower at this time and [making] commanded configuration changes and running the landing checklist but the stagnation continued. I was waiting for the autothrust to give him additional power and it never came. Researching it later; below 3;200 radio altitude the autothrust should be more sensitive and should never accept the speeds that the aircraft was slowing too; well below the magenta bug. This makes me think there is a problem with the autothrust on approach with this aircraft. I then noticed he was taking an action; not necessarily what I would have done. He took the thrust and placed it in mct or slightly between climb and mct and moved it around a little seeming to be trying to get the thrust up. After seeing multiple mode changes and continued stagnation I called for a go-around. We never received a windshear warning but it seems as if it was windshear. I notified tower of the go-around and called positive rate. Captain responded with gear up and the speed increased quickly as if on the backside of the windshear. I mentally calculated it to be about a 30 KT shift and let ATC know. At this time the flap speeds were exceeded. I made a callout to pitch up since we were well below the command bars; more pitch was needed to get into the command bars or less power due to the intermediate go-around; the speed was increasing so fast that I treated it like a windshear and reconfigured the flaps on speed just announcing it and not waiting for the command. ATC assigned runway heading and 2;000 after we had already passed that altitude on our way to 2;700; I set 2;000 and selected and then ATC assigned 3;000; I set that altitude and selected. First and foremost I think the ATC facility should not have been using this runway. They continued to use it after we went around and announced the windshear. After landing we sat on the parallel taxiway watching the other aircraft land on [runway] 22 and seeing the lightning strikes that surrounded them and knowing they were just realizing it when the were coming through the base layer left me with a feeling of disappointment in ATC. I know they do not like changing runways around but when the other 3 directions did not have any convective activity and the winds were actually favoring landing on [runways] 4 or 31 according to the windsock; the runway change should happen faster. As far a piloting the aircraft goes. I feel more time training intermediate go-arounds and proper ways to turn off; when to turn off; and what to do when autothrust is not doing what is desired is needed. Trying to get the thrust to come up due to slow speed by bumping it up above climb is poor technique. The entire situation would have been prevented by simply turning off the autothrust and setting about 60% N1 for configuration full to fix the slow speed. This should be previously trained and frequently practiced on the line. Additional training should also be done on intermediate go-arounds and what to do with pitch and power and how long toga is needed. ATC increased the confusion of the situation by having a published altitude; followed by an altitude we were already passing (2;000 ft) followed by a new altitude (3;000 ft) in an already complex situation.
Original NASA ASRS Text
Title: A320 First Officer describes an ILS approach to Runway 22 at LGA with lightning; turbulence and possible windshear. The autothrust system is not maintaining the desired reference speed and the Captain's 'technique' to override it is not successful. A go-around is announced by the First Officer; above 1;000 FT; resulting in flap speed and altitude exceedances.
Narrative: While being vectored for the ILS 22 through moderate weather we turned base; then final; armed the approach and began the descent. We came through the bases of the clouds and it became obvious through multiple lightning strikes; the clouds we were in were very convective which we did not previously know. There were multiple lightning strikes around us and the airspeed began to stagnate. I announced the stagnation and decrease in airspeed to the Captain and he responded that he was seeing it to. This was still before the FAF between 3;000 and 2;000 FT. I was busy switching from Approach to Tower at this time and [making] commanded configuration changes and running the Landing Checklist but the stagnation continued. I was waiting for the autothrust to give him additional power and it never came. Researching it later; below 3;200 radio altitude the autothrust should be more sensitive and should never accept the speeds that the aircraft was slowing too; well below the magenta bug. This makes me think there is a problem with the autothrust on approach with this aircraft. I then noticed he was taking an action; not necessarily what I would have done. He took the thrust and placed it in MCT or slightly between CLB and MCT and moved it around a little seeming to be trying to get the thrust up. After seeing multiple mode changes and continued stagnation I called for a go-around. We never received a Windshear Warning but it seems as if it was windshear. I notified Tower of the go-around and called positive rate. Captain responded with gear up and the speed increased quickly as if on the backside of the windshear. I mentally calculated it to be about a 30 KT shift and let ATC know. At this time the flap speeds were exceeded. I made a callout to pitch up since we were well below the command bars; more pitch was needed to get into the command bars or less power due to the intermediate go-around; the speed was increasing so fast that I treated it like a windshear and reconfigured the flaps on speed just announcing it and not waiting for the command. ATC assigned runway heading and 2;000 after we had already passed that altitude on our way to 2;700; I set 2;000 and selected and then ATC assigned 3;000; I set that altitude and selected. First and foremost I think the ATC facility should not have been using this runway. They continued to use it after we went around and announced the windshear. After landing we sat on the parallel taxiway watching the other aircraft land on [Runway] 22 and seeing the lightning strikes that surrounded them and knowing they were just realizing it when the were coming through the base layer left me with a feeling of disappointment in ATC. I know they do not like changing runways around but when the other 3 directions did not have any Convective activity and the winds were actually favoring landing on [runways] 4 or 31 according to the windsock; the runway change should happen faster. As far a piloting the aircraft goes. I feel more time training intermediate go-arounds and proper ways to turn off; when to turn off; and what to do when autothrust is not doing what is desired is needed. Trying to get the thrust to come up due to slow speed by bumping it up above CLB is poor technique. The entire situation would have been prevented by simply turning off the autothrust and setting about 60% N1 for configuration full to fix the slow speed. This should be previously trained and frequently practiced on the line. Additional training should also be done on intermediate go-arounds and what to do with pitch and power and how long TOGA is needed. ATC increased the confusion of the situation by having a published altitude; followed by an altitude we were already passing (2;000 FT) followed by a new altitude (3;000 FT) in an already complex situation.
Data retrieved from NASA's ASRS site as of July 2013 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.