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Attributes | |
ACN | 720525 |
Time | |
Date | 200612 |
Place | |
Locale Reference | airport : geg.airport |
State Reference | WA |
Altitude | agl bound lower : 0 agl bound upper : 50 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : geg.tower |
Operator | common carrier : air carrier |
Make Model Name | B737-900 |
Operating Under FAR Part | Part 121 |
Flight Phase | landing : go around landing : roll |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Experience | flight time last 90 days : 200 flight time type : 8000 |
ASRS Report | 720525 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Events | |
Anomaly | other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | flight crew : executed go around |
Supplementary | |
Problem Areas | Aircraft Flight Crew Human Performance Weather |
Primary Problem | Ambiguous |
Narrative:
As we approached geg; the ATIS reported 2100 ft scattered with a higher overcast and 10 mi of visibility in light rain. The wind was reported 140 degrees at 4 KTS and the ILS/visual approach to runway 21 was in use. The departure station WX was very windy with gusts. As we approached the airport; we were informed by ATC that we would be the last aircraft landing on runway 21 that the airport was changing to runway 3. We asked about the wind and the current airport wind was reported to us verbally as 060 degrees at 6 KTS by approach control. A tailwind; but within our limits. We planned a flaps 40 degree landing at just under maximum gross landing weight; about 145.5 pounds maybe somewhat less than that. The reference speed was 141 KTS and the target speed was 146 KTS. Considering the ATIS reported WX; we were somewhat surprised that we had not seen the runway by 1000 ft AGL. No matter; we had briefed the approach and were fully configured and stabilized at 1000 ft. We broke out of a ragged overcast at approximately 500 ft AGL in what I would estimate as moderate rain. We had good visibility looking southwest; the worst of the shower seemed to be falling right over the arrival end of the runway. On very short final approach; somewhere between 100 ft and 50 ft AGL; I detected a rapid increase in the rate of descent. I responded by adding power and pitching up very slightly (emphasis on very). The increased sink rate did not seem to decrease towards normal so I continued to add more power. The aircraft touched down very firmly in the touchdown zone and bounced. I would estimate the ht of the bounce at least 10 ft; possibly more. Considering the significant amount of increased power that I had already added; continuing the landing at that point was not safe and we elected to go around. A normal go around was executed. A PA announcement to the customers was made. We returned for a normal landing on runway 3. I am at a failure to explain the reason for this sudden increase in our descent rate although it is important to say that at no time did the 'sink rate' annunciation of the GPWS activate. Upon reflection; I realize that I was a little surprised by the amount of crab angle that was necessary to maintain centerline with a wind reported at 060 degrees at 6 KTS. Unfortunately; I do not recall looking at the HUD which was in use to determine the actual wind. Things were happening pretty darned fast and the lighting was quite flat at the runway in rain with clearing to the west (our 12 O'clock position). It was a difficult visual picture. I did apply a 'small' amount of rudder in order to provide a little better alignment with the landing surface. My intention was to touch down in a crab position; just slightly less than the crab angle that would have been necessary if no side-slip had been used. I cannot correlate with certainty that the application of rudder coincided with the rapid increase in rate of descent. It is possible but I believe that the rapidly changing meteorological conditions could have more likely been the cause but it is impossible for me to say with certainty. I say again for emphasis that this all happened very; very quickly. After landing; we inspected the tailskid just to be certain that no ground contact had occurred and it was found to be uncompromised. No adverse passenger reaction was noticed although several customers exclaimed to me that they were quite scared and that my PA announcement had comforted them. I do not believe that any far's or SOP's were violated. Nevertheless; I wanted to get this into the database as a data point. One subjective comment that I would make is that I have flown the B737-900 several times lately with full loads and planned landing weight of maximum gross landing weight. I think that this airplane is really 'on the edge' in this confign. It is fine when the wind is calm and the skies are blue but when the WX is a little dodgy; this is the poorest flying airplane that I have ever flown. The flaps 40 degree blow-back issue notwithstanding; in my opinion this airplane is prone to the development of high sink rates. The high approach speeds necessary to avoid fuselage contact can be quite disconcerting when you havespent the last few days flying the B737-400 or the B737-700. I do not fly this aircraft very often and that lack of familiarity contributes to the possibility of handling errors by myself and my colleagues. I can think of only 1 specific recommendation that I would make: 1) prohibit tankering fuel on this airplane. The majority of the problems that I have encountered with this variant are almost always at or near maximum gross landing weight. When preventable; why would we compromise this aircraft's handling characteristics for economic gain. That's just my opinion. Better wind and WX updates from the geg tower would have potentially improved this scenario if indeed a wind shift or windshear had something to do with this occurrence. Secondly; attempt as much as possible to avoid landing this aircraft at maximum gross landing weight by prohibiting tankering.
Original NASA ASRS Text
Title: A B737-900 CAPT MADE A HARD LNDG AT GEG; RESULTING IN A HIGH BOUNCE. HE ELECTED TO GO AROUND FOR ANOTHER APCH AND LNDG. CAPT COMMENTS THAT THE B737-900 SEEMS TO BE VERY CRITICAL WHEN FLOWN HVY; AND OFTEN DEVELOPS HIGH SINK RATES NEAR THE GND.
Narrative: AS WE APCHED GEG; THE ATIS RPTED 2100 FT SCATTERED WITH A HIGHER OVCST AND 10 MI OF VISIBILITY IN LIGHT RAIN. THE WIND WAS RPTED 140 DEGS AT 4 KTS AND THE ILS/VISUAL APCH TO RWY 21 WAS IN USE. THE DEP STATION WX WAS VERY WINDY WITH GUSTS. AS WE APCHED THE ARPT; WE WERE INFORMED BY ATC THAT WE WOULD BE THE LAST ACFT LNDG ON RWY 21 THAT THE ARPT WAS CHANGING TO RWY 3. WE ASKED ABOUT THE WIND AND THE CURRENT ARPT WIND WAS RPTED TO US VERBALLY AS 060 DEGS AT 6 KTS BY APCH CTL. A TAILWIND; BUT WITHIN OUR LIMITS. WE PLANNED A FLAPS 40 DEG LNDG AT JUST UNDER MAX GROSS LNDG WT; ABOUT 145.5 LBS MAYBE SOMEWHAT LESS THAN THAT. THE REF SPD WAS 141 KTS AND THE TARGET SPD WAS 146 KTS. CONSIDERING THE ATIS RPTED WX; WE WERE SOMEWHAT SURPRISED THAT WE HAD NOT SEEN THE RWY BY 1000 FT AGL. NO MATTER; WE HAD BRIEFED THE APCH AND WERE FULLY CONFIGURED AND STABILIZED AT 1000 FT. WE BROKE OUT OF A RAGGED OVCST AT APPROX 500 FT AGL IN WHAT I WOULD ESTIMATE AS MODERATE RAIN. WE HAD GOOD VISIBILITY LOOKING SW; THE WORST OF THE SHOWER SEEMED TO BE FALLING RIGHT OVER THE ARR END OF THE RWY. ON VERY SHORT FINAL APCH; SOMEWHERE BTWN 100 FT AND 50 FT AGL; I DETECTED A RAPID INCREASE IN THE RATE OF DSCNT. I RESPONDED BY ADDING PWR AND PITCHING UP VERY SLIGHTLY (EMPHASIS ON VERY). THE INCREASED SINK RATE DID NOT SEEM TO DECREASE TOWARDS NORMAL SO I CONTINUED TO ADD MORE PWR. THE ACFT TOUCHED DOWN VERY FIRMLY IN THE TOUCHDOWN ZONE AND BOUNCED. I WOULD ESTIMATE THE HT OF THE BOUNCE AT LEAST 10 FT; POSSIBLY MORE. CONSIDERING THE SIGNIFICANT AMOUNT OF INCREASED PWR THAT I HAD ALREADY ADDED; CONTINUING THE LNDG AT THAT POINT WAS NOT SAFE AND WE ELECTED TO GO AROUND. A NORMAL GAR WAS EXECUTED. A PA ANNOUNCEMENT TO THE CUSTOMERS WAS MADE. WE RETURNED FOR A NORMAL LNDG ON RWY 3. I AM AT A FAILURE TO EXPLAIN THE REASON FOR THIS SUDDEN INCREASE IN OUR DSCNT RATE ALTHOUGH IT IS IMPORTANT TO SAY THAT AT NO TIME DID THE 'SINK RATE' ANNUNCIATION OF THE GPWS ACTIVATE. UPON REFLECTION; I REALIZE THAT I WAS A LITTLE SURPRISED BY THE AMOUNT OF CRAB ANGLE THAT WAS NECESSARY TO MAINTAIN CTRLINE WITH A WIND RPTED AT 060 DEGS AT 6 KTS. UNFORTUNATELY; I DO NOT RECALL LOOKING AT THE HUD WHICH WAS IN USE TO DETERMINE THE ACTUAL WIND. THINGS WERE HAPPENING PRETTY DARNED FAST AND THE LIGHTING WAS QUITE FLAT AT THE RWY IN RAIN WITH CLRING TO THE W (OUR 12 O'CLOCK POS). IT WAS A DIFFICULT VISUAL PICTURE. I DID APPLY A 'SMALL' AMOUNT OF RUDDER IN ORDER TO PROVIDE A LITTLE BETTER ALIGNMENT WITH THE LNDG SURFACE. MY INTENTION WAS TO TOUCH DOWN IN A CRAB POS; JUST SLIGHTLY LESS THAN THE CRAB ANGLE THAT WOULD HAVE BEEN NECESSARY IF NO SIDE-SLIP HAD BEEN USED. I CANNOT CORRELATE WITH CERTAINTY THAT THE APPLICATION OF RUDDER COINCIDED WITH THE RAPID INCREASE IN RATE OF DSCNT. IT IS POSSIBLE BUT I BELIEVE THAT THE RAPIDLY CHANGING METEOROLOGICAL CONDITIONS COULD HAVE MORE LIKELY BEEN THE CAUSE BUT IT IS IMPOSSIBLE FOR ME TO SAY WITH CERTAINTY. I SAY AGAIN FOR EMPHASIS THAT THIS ALL HAPPENED VERY; VERY QUICKLY. AFTER LNDG; WE INSPECTED THE TAILSKID JUST TO BE CERTAIN THAT NO GND CONTACT HAD OCCURRED AND IT WAS FOUND TO BE UNCOMPROMISED. NO ADVERSE PAX REACTION WAS NOTICED ALTHOUGH SEVERAL CUSTOMERS EXCLAIMED TO ME THAT THEY WERE QUITE SCARED AND THAT MY PA ANNOUNCEMENT HAD COMFORTED THEM. I DO NOT BELIEVE THAT ANY FAR'S OR SOP'S WERE VIOLATED. NEVERTHELESS; I WANTED TO GET THIS INTO THE DATABASE AS A DATA POINT. ONE SUBJECTIVE COMMENT THAT I WOULD MAKE IS THAT I HAVE FLOWN THE B737-900 SEVERAL TIMES LATELY WITH FULL LOADS AND PLANNED LNDG WT OF MAX GROSS LNDG WT. I THINK THAT THIS AIRPLANE IS REALLY 'ON THE EDGE' IN THIS CONFIGN. IT IS FINE WHEN THE WIND IS CALM AND THE SKIES ARE BLUE BUT WHEN THE WX IS A LITTLE DODGY; THIS IS THE POOREST FLYING AIRPLANE THAT I HAVE EVER FLOWN. THE FLAPS 40 DEG BLOW-BACK ISSUE NOTWITHSTANDING; IN MY OPINION THIS AIRPLANE IS PRONE TO THE DEVELOPMENT OF HIGH SINK RATES. THE HIGH APCH SPDS NECESSARY TO AVOID FUSELAGE CONTACT CAN BE QUITE DISCONCERTING WHEN YOU HAVESPENT THE LAST FEW DAYS FLYING THE B737-400 OR THE B737-700. I DO NOT FLY THIS ACFT VERY OFTEN AND THAT LACK OF FAMILIARITY CONTRIBUTES TO THE POSSIBILITY OF HANDLING ERRORS BY MYSELF AND MY COLLEAGUES. I CAN THINK OF ONLY 1 SPECIFIC RECOMMENDATION THAT I WOULD MAKE: 1) PROHIBIT TANKERING FUEL ON THIS AIRPLANE. THE MAJORITY OF THE PROBS THAT I HAVE ENCOUNTERED WITH THIS VARIANT ARE ALMOST ALWAYS AT OR NEAR MAX GROSS LNDG WT. WHEN PREVENTABLE; WHY WOULD WE COMPROMISE THIS ACFT'S HANDLING CHARACTERISTICS FOR ECONOMIC GAIN. THAT'S JUST MY OPINION. BETTER WIND AND WX UPDATES FROM THE GEG TWR WOULD HAVE POTENTIALLY IMPROVED THIS SCENARIO IF INDEED A WIND SHIFT OR WINDSHEAR HAD SOMETHING TO DO WITH THIS OCCURRENCE. SECONDLY; ATTEMPT AS MUCH AS POSSIBLE TO AVOID LNDG THIS ACFT AT MAX GROSS LNDG WT BY PROHIBITING TANKERING.
Data retrieved from NASA's ASRS site as of January 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.