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B737 first officer fails to advocate for go around when cap accepts a lahso clearance for runway 22R at ord. Winds were out of limits for the lahso.
| Attributes | |
| ACN | 798097 |
| Time | |
| Date | 200808 |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | airport : ord.airport |
| State Reference | IL |
| Altitude | msl single value : 10000 |
| Aircraft 1 | |
| Controlling Facilities | tower : ord.tower |
| Operator | common carrier : air carrier |
| Make Model Name | B737 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : approach |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Experience | flight time last 90 days : 160 flight time total : 6000 flight time type : 500 |
| ASRS Report | 798097 |
| Events | |
| Anomaly | non adherence : company policies non adherence : far other anomaly |
| Independent Detector | other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Weather ATC Human Performance |
| Primary Problem | Flight Crew Human Performance |
Narrative:
On approach to ord in VMC; on a vector (essentially right base for runway 22R); the approach controller said they 'lost the winds' for lahso for runway 22R. ATIS winds were 310 degrees at 7 KTS gusting to 16 KTS. Soon after that; he switched us to tower. Tower cleared us to land with 'lahso runway 27L' instructions. I asked the captain if he wanted me to reach back and accept the lahso; he said yes. I had used ACARS to pull up the landing data which showed brakes 'maximum' or 'off' as the full length braking options and winds with 0 degrees headwind/10(?) degree KT direct crosswind. At 1000 ft I stated 'instruments crosschecked; GS approaching 1 DOT low.' at 500 ft I stated '500 ft; 1 DOT low.' around 100-200 ft (I'm not sure) I stated 'GS approaching 2 dots low' after which point we got an audible 'GS' warning from the GPWS. It was at that point I realized flying the GS 1 DOT low had been the plan. I'm a little dense sometimes and hadn't realized that was the captain's way to assure complying with the lahso instruction. The captain landed; used maximum braking; complied with lahso and made the A1 turnoff. I now believe the winds had shifted to 320 degrees or more northerly and that there had been a tailwind on approach which would have prevented us from accepting a lahso. I also believe the tower controller knew this but didn't advise us. How else would the approach controller have known? I was hesitant to call for a go around below 200 ft when we got the warning because of: 1) he's the captain and had a plan. 2) we were VMC in good WX. 3) a go around with intersecting runway departure paths might be less safe than being low on GS. 4) landing on the runway was assured. I also think that requesting a wind check might have forced the controller's hand by requiring him to tell us the current winds (which I suspect were beyond lahso limits). I was too preoccupied with being below GS and having a 'not so good' gut feeling to request a wind check.
Original NASA ASRS Text
Title: B737 FO FAILS TO ADVOCATE FOR GAR WHEN CAP ACCEPTS A LAHSO CLRNC FOR RWY 22R AT ORD. WINDS WERE OUT OF LIMITS FOR THE LAHSO.
Narrative: ON APCH TO ORD IN VMC; ON A VECTOR (ESSENTIALLY R BASE FOR RWY 22R); THE APCH CTLR SAID THEY 'LOST THE WINDS' FOR LAHSO FOR RWY 22R. ATIS WINDS WERE 310 DEGS AT 7 KTS GUSTING TO 16 KTS. SOON AFTER THAT; HE SWITCHED US TO TWR. TWR CLRED US TO LAND WITH 'LAHSO RWY 27L' INSTRUCTIONS. I ASKED THE CAPT IF HE WANTED ME TO REACH BACK AND ACCEPT THE LAHSO; HE SAID YES. I HAD USED ACARS TO PULL UP THE LNDG DATA WHICH SHOWED BRAKES 'MAX' OR 'OFF' AS THE FULL LENGTH BRAKING OPTIONS AND WINDS WITH 0 DEGS HEADWIND/10(?) DEG KT DIRECT XWIND. AT 1000 FT I STATED 'INSTS XCHKED; GS APCHING 1 DOT LOW.' AT 500 FT I STATED '500 FT; 1 DOT LOW.' AROUND 100-200 FT (I'M NOT SURE) I STATED 'GS APCHING 2 DOTS LOW' AFTER WHICH POINT WE GOT AN AUDIBLE 'GS' WARNING FROM THE GPWS. IT WAS AT THAT POINT I REALIZED FLYING THE GS 1 DOT LOW HAD BEEN THE PLAN. I'M A LITTLE DENSE SOMETIMES AND HADN'T REALIZED THAT WAS THE CAPT'S WAY TO ASSURE COMPLYING WITH THE LAHSO INSTRUCTION. THE CAPT LANDED; USED MAX BRAKING; COMPLIED WITH LAHSO AND MADE THE A1 TURNOFF. I NOW BELIEVE THE WINDS HAD SHIFTED TO 320 DEGS OR MORE NORTHERLY AND THAT THERE HAD BEEN A TAILWIND ON APCH WHICH WOULD HAVE PREVENTED US FROM ACCEPTING A LAHSO. I ALSO BELIEVE THE TWR CTLR KNEW THIS BUT DIDN'T ADVISE US. HOW ELSE WOULD THE APCH CTLR HAVE KNOWN? I WAS HESITANT TO CALL FOR A GAR BELOW 200 FT WHEN WE GOT THE WARNING BECAUSE OF: 1) HE'S THE CAPT AND HAD A PLAN. 2) WE WERE VMC IN GOOD WX. 3) A GAR WITH INTERSECTING RWY DEP PATHS MIGHT BE LESS SAFE THAN BEING LOW ON GS. 4) LNDG ON THE RWY WAS ASSURED. I ALSO THINK THAT REQUESTING A WIND CHK MIGHT HAVE FORCED THE CTLR'S HAND BY REQUIRING HIM TO TELL US THE CURRENT WINDS (WHICH I SUSPECT WERE BEYOND LAHSO LIMITS). I WAS TOO PREOCCUPIED WITH BEING BELOW GS AND HAVING A 'NOT SO GOOD' GUT FEELING TO REQUEST A WIND CHK.
Data retrieved from NASA's ASRS site as of May 2009 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.