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|
Attributes | |
ACN | 394729 |
Time | |
Date | 199802 |
Day | Tue |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : sfo |
State Reference | CA |
Altitude | msl bound lower : 2000 msl bound upper : 2000 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tracon : oak |
Operator | common carrier : air carrier |
Make Model Name | A320 |
Operating Under FAR Part | Part 121 |
Navigation In Use | Other Other |
Flight Phase | descent : approach |
Route In Use | approach : visual enroute : on vectors |
Flight Plan | IFR |
Aircraft 2 | |
Operator | common carrier : air carrier |
Make Model Name | B757 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Navigation In Use | Other Other |
Flight Phase | descent : approach |
Route In Use | approach : visual arrival other enroute : on vectors |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : atp |
Experience | flight time last 90 days : 60 flight time total : 6500 flight time type : 60 |
ASRS Report | 394729 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : flight engineer pilot : atp |
Experience | flight time last 90 days : 100 flight time total : 11500 flight time type : 100 |
ASRS Report | 394880 |
Events | |
Anomaly | non adherence : clearance other anomaly other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | none taken : unable |
Consequence | Other |
Miss Distance | horizontal : 1000 vertical : 0 |
Supplementary | |
Primary Problem | ATC Human Performance |
Air Traffic Incident | Intra Facility Coordination Failure |
Situations | |
ATC Facility | procedure or policy : unspecified |
Narrative:
Initial approach controller told us to expect vectors for an ILS to runway 28R at sfo. Upon arriving at the VOR we received vectors for an apparent left downwind. Flight conditions were smooth and VFR, however, we could see a lower cloud level on the final to both runways 28R and 28L and assumed we would be doing an actual ILS approach. Asking the second approach controller for a 'rough idea' of a sequence we got an ambiguous reply about changing something and he had no idea. We started getting vectors for base and queried whether we were going for the left or right side. We were told the left. I quickly changed it in the mcdu which is the only way to tune a localizer in the airbus. We were still VMC and realized our clearance might be a visual as we were told to report a B757 at our 2:30 O'clock position. Our assigned speed since the sfo VOR was 180 KTS. Realizing that we could maintain VMC to the airport and having the B757 in sight reported so. Our clearance was now to maintain 180 KTS to the bridge and visual with the B757 cleared the visual to runway 28L tower now. Actually, both us and the B757 arrived converging over the bridge simultaneously. TCASII was on a TA only and the winds were a slight left quartering headwind. Realizing that the B757 was slowing down more than us, we kept our speed and pulled slowly ahead. We landed on runway 28L at AB29 local. Meeting the B757 captain in the terminal later he told us that he was told to maintain 160 KTS to the bridge and that the airbus would follow him, when he realized that we both converged on our respective final approachs. Simultaneously, he elected to slow back to final speed. He was a bit upset that we went ahead and he landed at AB30 on runway 28R. When we relayed our side, we both realized that both approach controllers probably weren't 'talking' to each other which led to the confusion about sequence. We were both VMC and safety was never compromised but sfo bay approach controllers have been 'relaxed recently and sometimes this leads to 'compromisable' sits. Supplemental information from acn 394880: an area of conflict arises between a visual approach clearance and an approach controller stipulation to maintain a specific airspeed.
Original NASA ASRS Text
Title: AN A320 FLC'S RPT ON A CONFUSING, COMPROMISING INCIDENT WHILE OPERATING ON A PARALLEL VISUAL TO RWYS 28L-R AT SFO. EVENT INDICATED A 'LACK OF COORD' BTWN THE 2 APCH CTLRS WHO WERE ON SEPARATE FREQS.
Narrative: INITIAL APCH CTLR TOLD US TO EXPECT VECTORS FOR AN ILS TO RWY 28R AT SFO. UPON ARRIVING AT THE VOR WE RECEIVED VECTORS FOR AN APPARENT L DOWNWIND. FLT CONDITIONS WERE SMOOTH AND VFR, HOWEVER, WE COULD SEE A LOWER CLOUD LEVEL ON THE FINAL TO BOTH RWYS 28R AND 28L AND ASSUMED WE WOULD BE DOING AN ACTUAL ILS APCH. ASKING THE SECOND APCH CTLR FOR A 'ROUGH IDEA' OF A SEQUENCE WE GOT AN AMBIGUOUS REPLY ABOUT CHANGING SOMETHING AND HE HAD NO IDEA. WE STARTED GETTING VECTORS FOR BASE AND QUERIED WHETHER WE WERE GOING FOR THE L OR R SIDE. WE WERE TOLD THE L. I QUICKLY CHANGED IT IN THE MCDU WHICH IS THE ONLY WAY TO TUNE A LOC IN THE AIRBUS. WE WERE STILL VMC AND REALIZED OUR CLRNC MIGHT BE A VISUAL AS WE WERE TOLD TO RPT A B757 AT OUR 2:30 O'CLOCK POS. OUR ASSIGNED SPD SINCE THE SFO VOR WAS 180 KTS. REALIZING THAT WE COULD MAINTAIN VMC TO THE ARPT AND HAVING THE B757 IN SIGHT RPTED SO. OUR CLRNC WAS NOW TO MAINTAIN 180 KTS TO THE BRIDGE AND VISUAL WITH THE B757 CLRED THE VISUAL TO RWY 28L TWR NOW. ACTUALLY, BOTH US AND THE B757 ARRIVED CONVERGING OVER THE BRIDGE SIMULTANEOUSLY. TCASII WAS ON A TA ONLY AND THE WINDS WERE A SLIGHT L QUARTERING HEADWIND. REALIZING THAT THE B757 WAS SLOWING DOWN MORE THAN US, WE KEPT OUR SPD AND PULLED SLOWLY AHEAD. WE LANDED ON RWY 28L AT AB29 LCL. MEETING THE B757 CAPT IN THE TERMINAL LATER HE TOLD US THAT HE WAS TOLD TO MAINTAIN 160 KTS TO THE BRIDGE AND THAT THE AIRBUS WOULD FOLLOW HIM, WHEN HE REALIZED THAT WE BOTH CONVERGED ON OUR RESPECTIVE FINAL APCHS. SIMULTANEOUSLY, HE ELECTED TO SLOW BACK TO FINAL SPD. HE WAS A BIT UPSET THAT WE WENT AHEAD AND HE LANDED AT AB30 ON RWY 28R. WHEN WE RELAYED OUR SIDE, WE BOTH REALIZED THAT BOTH APCH CTLRS PROBABLY WEREN'T 'TALKING' TO EACH OTHER WHICH LED TO THE CONFUSION ABOUT SEQUENCE. WE WERE BOTH VMC AND SAFETY WAS NEVER COMPROMISED BUT SFO BAY APCH CTLRS HAVE BEEN 'RELAXED RECENTLY AND SOMETIMES THIS LEADS TO 'COMPROMISABLE' SITS. SUPPLEMENTAL INFO FROM ACN 394880: AN AREA OF CONFLICT ARISES BTWN A VISUAL APCH CLRNC AND AN APCH CTLR STIPULATION TO MAINTAIN A SPECIFIC AIRSPD.
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.