NASA · Aviation Safety Reporting System
B737 NG Flight Crew reported receiving a terrain warning on short final approach to DEN airport due to flap misconfiguration. Flight crew stated they received a late runway change which resulted in a higher-than-normal rate of descent and not completing a checklist.
What is ASRS?
The Aviation Safety Reporting System is NASA's voluntary, confidential, non- punitive incident-reporting system, established 1976. Pilots, controllers, dispatchers, and maintenance technicians file reports describing safety- relevant events. NASA de-identifies every report before adding it to the public database. Reports are not investigated by NASA, the FAA, or the NTSB — they represent the reporter's perspective.
Pilot narratives
Verbatim from the de-identified NASA record. First-person account by the
reporter. NASA strips identifying details (names, company, specific time);
anonymization placeholders are ZZZ,
X, Y.
Reporter 1
We received a clearance for a visual approach to [Runway] 35L with direct to the FAF. I was monitoring our class B floor to ensure compliance and the FO was flying 250 knots. I stepped down his altitude as required to remain in class B. ATC told us the airspeed was our discretion. As we approached the final marker we were high and fast. We did not intercept the glide slope at the marker and used vertical speed to continue. At 500 feet we were stable, but I did not get our flaps to 30. I did not hear a call and we were focused on salvaging the approach. The GPWS said "terrain" and I thought this was an error. At 50 feet I noticed the flap gauge at 25. Our Vref was 164 knots due to gusts. Clearly we should have gone around and I offer no excuse.
Reporter 2
Expected ILS 35L at DEN, was given [Runway] 35R late in the descent. Pilot Flying changed ILS radio and minimus; however PF failed to change the runway in the ARR Page on the FMC. ILS 35R became visual 35R per approach control, which wasn't unexpected based on ATIS information. When the omission of the ARR runway was realized and was entered we lost vertical guidance on the PFD and added to the task saturation in the cockpit. PF attempted to slow to from 250 to 210 at approx 7 miles from FRONZ (FAF for 35R) on a 45 deg dogleg vector off the CLASH Arrival. Had to stay high due to Class B airspace airspeed restrictions, then was late to get down to 7000 feet by FRONZ which resulted in having to stay high and configure. Aircraft was high at FRONZ and for the remainder of the approach into 35R. Being high approaching FRONZ, attempted to utilize V/S Mode to capture the glide path, which resulted in a higher than necessary airspeed which then resulted in a late configuration and continuance above acceptable parameters for landing. Attempted to continue to recover the approach while still high and configuring the aircraft to a greater rate of descent to capture a stabilized approach. By 500 feet, was in excess of 1000 feet per/minute and only Flaps 25 with 1 Red and 3 white on the PAPIs Called for flaps 30 but did not verify flap movement and did not verify completion of landing checklist which would have precluded "Too Low Terrain" annunciation. Continued to landing which was uneventful and within acceptable landing parameters on the runway.
NASA classification — Anomalies
- Deviation - Altitude
- Deviation - Speed
- Deviation / Discrepancy - Procedural
- Inflight Event / Encounter
NASA classification — Assessments
- Contributing Factors / Situations
- Human Factors · Procedure
- Primary Problem
- Ambiguous
ASRS reports are voluntarily submitted, de-identified by NASA, and represent the reporter's perspective. The presence of reports on a topic cannot be used to infer prevalence in the National Airspace System. The authoritative source is the NASA ASRS Database Online at asrs.arc.nasa.gov ↗.