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Air carrier large transport report on bay approach controller technique ATC requiring an altitude crossing restr on runway 19L visual approach of '3000 ft until the 8 DME.' clearance interpretation problem with regards to using either the VOR or ILS DME. The altitude crossing would result in a violation of the stabilized approach concept. Altitude deviation crossing restr not met.
| Attributes | |
| ACN | 354940 |
| Time | |
| Date | 199612 |
| Day | Sat |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : sfo |
| State Reference | CA |
| Altitude | msl bound lower : 2500 msl bound upper : 3000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : oak |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | descent : approach descent other |
| Route In Use | approach : visual arrival other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : flight engineer pilot : atp |
| Experience | flight time last 90 days : 150 flight time total : 8000 flight time type : 500 |
| ASRS Report | 354940 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met altitude deviation : overshoot non adherence : published procedure non adherence : clearance other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Consequence | Other |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Pilot Deviation other |
| Situations | |
| ATC Facility | procedure or policy : unspecified |
Narrative:
Called field in sight and then cleared by approach for a visual approach to runway 19L sfo 'maintain 3000 ft until 8 DME.' PNF switched to isia raw data for DME and said 'on ILS for the DME.' received no acknowledgment from PF. PF was set up on FMC for the ILS 19L with progress page displayed for distance to go information. PNF checked altitude and saw 2700 ft then DME (isia) 9.0. PNF said 'we're clear to 3000 ft until 8 DME?' PF responded 'I'm above the GS, I've got 5 mi to the runway' pointing to the progress page on the FMC. At this point we crossed 8.0 DME at 2500 ft MSL still above the GS. During arrival received numerous speed altitude and heading changes (many more than ordinary). Held high through most of the arrival and requested to maintain 180 KTS until 5 mi. PF had interpreted the approach plate as the GS would provide altitude clearance to meet the 3000 ft at 8 DME restr. PNF had assumed PF knew raw data DME was available on the right distance display of the right distance measuring equipment. ATC did not specify 8 DME from what navigation, sfo? Isia? Complying with the altitude/airspeed restrs would have resulted in a go around since we would have a difficult time meeting the company's requirements to be stabilized on the approach by 1000 ft AGL (visual). No conflicts or TCASII alerts or advisories occurred throughout the approach. The landing was uneventful after sidestepping to runway 29R at tower's request.
Original NASA ASRS Text
Title: ACR LGT RPT ON BAY APCH CTLR TECHNIQUE ATC REQUIRING AN ALT XING RESTR ON RWY 19L VISUAL APCH OF '3000 FT UNTIL THE 8 DME.' CLRNC INTERP PROB WITH REGARDS TO USING EITHER THE VOR OR ILS DME. THE ALT XING WOULD RESULT IN A VIOLATION OF THE STABILIZED APCH CONCEPT. ALTDEV XING RESTR NOT MET.
Narrative: CALLED FIELD IN SIGHT AND THEN CLRED BY APCH FOR A VISUAL APCH TO RWY 19L SFO 'MAINTAIN 3000 FT UNTIL 8 DME.' PNF SWITCHED TO ISIA RAW DATA FOR DME AND SAID 'ON ILS FOR THE DME.' RECEIVED NO ACKNOWLEDGMENT FROM PF. PF WAS SET UP ON FMC FOR THE ILS 19L WITH PROGRESS PAGE DISPLAYED FOR DISTANCE TO GO INFO. PNF CHKED ALT AND SAW 2700 FT THEN DME (ISIA) 9.0. PNF SAID 'WE'RE CLR TO 3000 FT UNTIL 8 DME?' PF RESPONDED 'I'M ABOVE THE GS, I'VE GOT 5 MI TO THE RWY' POINTING TO THE PROGRESS PAGE ON THE FMC. AT THIS POINT WE CROSSED 8.0 DME AT 2500 FT MSL STILL ABOVE THE GS. DURING ARR RECEIVED NUMEROUS SPD ALT AND HEADING CHANGES (MANY MORE THAN ORDINARY). HELD HIGH THROUGH MOST OF THE ARR AND REQUESTED TO MAINTAIN 180 KTS UNTIL 5 MI. PF HAD INTERPRETED THE APCH PLATE AS THE GS WOULD PROVIDE ALT CLRNC TO MEET THE 3000 FT AT 8 DME RESTR. PNF HAD ASSUMED PF KNEW RAW DATA DME WAS AVAILABLE ON THE RIGHT DISTANCE DISPLAY OF THE RIGHT DISTANCE MEASURING EQUIP. ATC DID NOT SPECIFY 8 DME FROM WHAT NAV, SFO? ISIA? COMPLYING WITH THE ALT/AIRSPD RESTRS WOULD HAVE RESULTED IN A GAR SINCE WE WOULD HAVE A DIFFICULT TIME MEETING THE COMPANY'S REQUIREMENTS TO BE STABILIZED ON THE APCH BY 1000 FT AGL (VISUAL). NO CONFLICTS OR TCASII ALERTS OR ADVISORIES OCCURRED THROUGHOUT THE APCH. THE LNDG WAS UNEVENTFUL AFTER SIDESTEPPING TO RWY 29R AT TWR'S REQUEST.
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.