B737-700
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 429; Flight Crew Type 8300
Situational Awareness; Workload
Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter CFTT / CFIT
General None Reported / Taken
Human Factors; Weather
While on the LGA LOC Runway 31 Approach at the final approach fix; we got a Caution Obstacle Warning while we were descending from the final approach fix (FARBY). The warning came on once and I continued because I was configured to land and the speed bug was close to the flap overspeed. I initially did not hear the warning because I was task saturated and listening to two radios at the same time while managing speed; altitude; and attitude all while in light to moderate chop. The First Officer notified me after the fact that the warning happened once. Since it was after the fact I continued the approach stabilized. In retrospect I should have initiated a go-around immediately. The approach winds were very turbulent at the time; and visibility was VFR.
We were running late at night into LGA. ATIS reported gusty winds; and Tower was calling a windshear report around 400 feet. We were configured flaps 40 with gear down. The Pilot Flying was fighting to keep the aircraft on the visual glideslope; and I was watching the airspeed because of the high gust factor and flaps 40 configuration. The aircraft started to sink slightly and speed dropped off. The Pilot Flying began to correct for both speed and altitude when we got a Caution Obstacle. I had the obstacle in sight and we were already back on the visual glideslope. At the time; I experienced some negative transfer from a previous aircraft where the crew could elect to continue with a caution as long as the flight path was corrected and the obstacle in sight; day or night. After landing; I remembered the night restriction in the maneuvers section and we discussed the incident as a crew during the [next] leg.
B737-700 flight crew reported continuing the approach to landing after receiving a GPWS obstacle warning on a night visual approach to LGA Runway 31.