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|
Attributes | |
ACN | 260679 |
Time | |
Date | 199401 |
Day | Tue |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : gcn |
State Reference | AZ |
Altitude | msl bound lower : 8500 msl bound upper : 10500 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zla tower : sna |
Operator | common carrier : air carrier |
Make Model Name | Twin Otter DHC-6 |
Operating Under FAR Part | Part 135 |
Flight Phase | cruise other |
Flight Plan | VFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : instrument pilot : atp pilot : cfi |
Experience | flight time last 90 days : 100 flight time total : 4600 flight time type : 2900 |
ASRS Report | 260679 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : instrument pilot : commercial |
Events | |
Anomaly | altitude deviation : excursion from assigned altitude non adherence : far non adherence : published procedure other anomaly other |
Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
Resolutory Action | none taken : detected after the fact |
Consequence | Other |
Supplementary | |
Primary Problem | Flight Crew Human Performance |
Air Traffic Incident | Pilot Deviation |
Narrative:
I was captain on airlines flight from grand canyon, az, to las vegas, nv. We initially made a slow climb on departure to 10500 ft MSL on the sfar 50-2 blue-direct south route with the intention of descending west of grand canyon west airport, just outside the sfar. However, upon reaching 10500 ft, we discovered winds aloft far greater than forecast, approximately 40 KTS, causing us an effective ground speed of approximately 110 KTS. At this rate, we would not clear grand canyon west airport at 10500 ft before exceeding our far part 135 oxygen limit of 30 mins. Accordingly, we descended to 8500 ft, with the intention of climbing, again, above the gcn minimum crossing altitude of 9000 ft (8500 ft is an acceptable en route altitude, but any change in altitude within the sfar requires a deviation report). We announced our intentions, and the actual descent on the applicable sector frequencys, and left all our lights on during the descent. However, at 8500 ft, I discovered the winds as great as 10500 ft. I proceeded to make some quick calculations as to fuel consumption, time of arrival, etc, and reported to our company dispatcher. Our dispatcher seemed unimpressed, and said they've known about the winds all day (nobody informed us). Meanwhile, we forgot to climb, again, over gcw, thus violating the MCA over that airport. To make matters worse for myself, I even made a voluntary position report over gcw at 8500 ft (I meant to keep any other traffic advised, but instead, incriminated myself). I discovered my error after landing. I got distracted and made a mistake. I have not made this mistake before, and I will not make it again. But, as a practical matter, I think the combination of mandatory rtes, altitudes, and MCA's, in conjunction with the oxygen requirements of far part 135 are onerous. It's a 'gotcha' that offers no real increase to flight safety, and, in fact, hinders flight safety if it means that a pilot should remain silent on the radio so as not to incriminate himself. An MCA over cgw of 8500 ft would do much for simplifying things and eliminating bureaucratic headaches.
Original NASA ASRS Text
Title: CAPT OF AN SMT ACR ACFT INADVERTENTLY FLEW BELOW REQUIRED RTE ALT IN A SPECIAL FLT RULES AREA.
Narrative: I WAS CAPT ON AIRLINES FLT FROM GRAND CANYON, AZ, TO LAS VEGAS, NV. WE INITIALLY MADE A SLOW CLB ON DEP TO 10500 FT MSL ON THE SFAR 50-2 BLUE-DIRECT S RTE WITH THE INTENTION OF DSNDING W OF GRAND CANYON WEST ARPT, JUST OUTSIDE THE SFAR. HOWEVER, UPON REACHING 10500 FT, WE DISCOVERED WINDS ALOFT FAR GREATER THAN FORECAST, APPROX 40 KTS, CAUSING US AN EFFECTIVE GND SPD OF APPROX 110 KTS. AT THIS RATE, WE WOULD NOT CLR GRAND CANYON WEST ARPT AT 10500 FT BEFORE EXCEEDING OUR FAR PART 135 OXYGEN LIMIT OF 30 MINS. ACCORDINGLY, WE DSNDED TO 8500 FT, WITH THE INTENTION OF CLBING, AGAIN, ABOVE THE GCN MINIMUM XING ALT OF 9000 FT (8500 FT IS AN ACCEPTABLE ENRTE ALT, BUT ANY CHANGE IN ALT WITHIN THE SFAR REQUIRES A DEV RPT). WE ANNOUNCED OUR INTENTIONS, AND THE ACTUAL DSCNT ON THE APPLICABLE SECTOR FREQS, AND LEFT ALL OUR LIGHTS ON DURING THE DSCNT. HOWEVER, AT 8500 FT, I DISCOVERED THE WINDS AS GREAT AS 10500 FT. I PROCEEDED TO MAKE SOME QUICK CALCULATIONS AS TO FUEL CONSUMPTION, TIME OF ARR, ETC, AND RPTED TO OUR COMPANY DISPATCHER. OUR DISPATCHER SEEMED UNIMPRESSED, AND SAID THEY'VE KNOWN ABOUT THE WINDS ALL DAY (NOBODY INFORMED US). MEANWHILE, WE FORGOT TO CLB, AGAIN, OVER GCW, THUS VIOLATING THE MCA OVER THAT ARPT. TO MAKE MATTERS WORSE FOR MYSELF, I EVEN MADE A VOLUNTARY POS RPT OVER GCW AT 8500 FT (I MEANT TO KEEP ANY OTHER TFC ADVISED, BUT INSTEAD, INCRIMINATED MYSELF). I DISCOVERED MY ERROR AFTER LNDG. I GOT DISTRACTED AND MADE A MISTAKE. I HAVE NOT MADE THIS MISTAKE BEFORE, AND I WILL NOT MAKE IT AGAIN. BUT, AS A PRACTICAL MATTER, I THINK THE COMBINATION OF MANDATORY RTES, ALTS, AND MCA'S, IN CONJUNCTION WITH THE OXYGEN REQUIREMENTS OF FAR PART 135 ARE ONEROUS. IT'S A 'GOTCHA' THAT OFFERS NO REAL INCREASE TO FLT SAFETY, AND, IN FACT, HINDERS FLT SAFETY IF IT MEANS THAT A PLT SHOULD REMAIN SILENT ON THE RADIO SO AS NOT TO INCRIMINATE HIMSELF. AN MCA OVER CGW OF 8500 FT WOULD DO MUCH FOR SIMPLIFYING THINGS AND ELIMINATING BUREAUCRATIC HEADACHES.
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.