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A B737 flight crew has problems in bracketing the localizer and GS during a manually flown nonstabilized ILS approach to phl, PA.
| Attributes | |
| ACN | 434850 |
| Time | |
| Date | 199904 |
| Day | Fri |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : phl.airport |
| State Reference | PA |
| Altitude | agl single value : 300 |
| Environment | |
| Flight Conditions | IMC |
| Weather Elements | other |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tower : phl.tower |
| Operator | common carrier : air carrier |
| Make Model Name | B737-400 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | ils localizer & glide slope : ns |
| Flight Phase | descent : approach descent : intermediate altitude |
| Route In Use | approach : instrument precision |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Experience | flight time last 90 days : 80 flight time total : 4000 flight time type : 80 |
| ASRS Report | 434850 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | non adherence : company policies non adherence : published procedure other anomaly |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Initial approach normal. Approach mode was not armed, autoplt on aircraft tracked localizer. At FAF, aircraft overshot GS. Captain called 'lower nose' and took control. Autoplt was disconnected and I (first officer) xferred control to captain and started (PNF) standard callouts, '1000 ft,' '500 ft.' however, approach was never really stabilized. The captain asked if I wanted the aircraft back at 500 ft AGL. I accepted control back again and started a left correction to get localizer back, which was 1/4 deflection left (full scale on expanded EFIS localizer display). Autoplt remained off and approach mode was never selected so raw data approach was flown (fl) was also off. The PNF (captain) did not make 'approaching min' and 'minimums' callouts, but near 'minimums' called 'full deflection' referring to the expanded 1/4 scale localizer. The runway became visible to me slightly right of nose. I started right turn. Aircraft was in position to land with normal maneuvering and was approximately on glide path, slightly left. Captain again called 'lower nose' and then took control again, landing aircraft. Corrective action: arm approach as soon as cleared by ATC. If control is xferred during initial approach (as in this case), do not xfer back again, in IMC, as confusion and missed callouts are likely. Also, if (forgot) approach mode is not armed, suggest using vertical speed to capture GS from above, arming approach and keep autoplt on to have stabilized approach by 1000 ft AGL (per SOP's) or 500 ft VFR! Otherwise 'miss approach.'
Original NASA ASRS Text
Title: A B737 FLC HAS PROBS IN BRACKETING THE LOC AND GS DURING A MANUALLY FLOWN NONSTABILIZED ILS APCH TO PHL, PA.
Narrative: INITIAL APCH NORMAL. APCH MODE WAS NOT ARMED, AUTOPLT ON ACFT TRACKED LOC. AT FAF, ACFT OVERSHOT GS. CAPT CALLED 'LOWER NOSE' AND TOOK CTL. AUTOPLT WAS DISCONNECTED AND I (FO) XFERRED CTL TO CAPT AND STARTED (PNF) STANDARD CALLOUTS, '1000 FT,' '500 FT.' HOWEVER, APCH WAS NEVER REALLY STABILIZED. THE CAPT ASKED IF I WANTED THE ACFT BACK AT 500 FT AGL. I ACCEPTED CTL BACK AGAIN AND STARTED A L CORRECTION TO GET LOC BACK, WHICH WAS 1/4 DEFLECTION L (FULL SCALE ON EXPANDED EFIS LOC DISPLAY). AUTOPLT REMAINED OFF AND APCH MODE WAS NEVER SELECTED SO RAW DATA APCH WAS FLOWN (FL) WAS ALSO OFF. THE PNF (CAPT) DID NOT MAKE 'APCHING MIN' AND 'MINIMUMS' CALLOUTS, BUT NEAR 'MINIMUMS' CALLED 'FULL DEFLECTION' REFERRING TO THE EXPANDED 1/4 SCALE LOC. THE RWY BECAME VISIBLE TO ME SLIGHTLY R OF NOSE. I STARTED R TURN. ACFT WAS IN POS TO LAND WITH NORMAL MANEUVERING AND WAS APPROX ON GLIDE PATH, SLIGHTLY L. CAPT AGAIN CALLED 'LOWER NOSE' AND THEN TOOK CTL AGAIN, LNDG ACFT. CORRECTIVE ACTION: ARM APCH AS SOON AS CLRED BY ATC. IF CTL IS XFERRED DURING INITIAL APCH (AS IN THIS CASE), DO NOT XFER BACK AGAIN, IN IMC, AS CONFUSION AND MISSED CALLOUTS ARE LIKELY. ALSO, IF (FORGOT) APCH MODE IS NOT ARMED, SUGGEST USING VERT SPD TO CAPTURE GS FROM ABOVE, ARMING APCH AND KEEP AUTOPLT ON TO HAVE STABILIZED APCH BY 1000 FT AGL (PER SOP'S) OR 500 FT VFR! OTHERWISE 'MISS APCH.'
Data retrieved from NASA's ASRS site as of July 2007 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.