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|
Attributes | |
ACN | 107823 |
Time | |
Date | 198903 |
Day | Fri |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | atc facility : bal |
State Reference | MD |
Altitude | msl bound lower : 15000 msl bound upper : 15000 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Navigation In Use | Other Other |
Flight Phase | other |
Route In Use | enroute airway : v93 |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : atp pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi |
Experience | flight time last 90 days : 95 flight time total : 6000 flight time type : 1500 |
ASRS Report | 107823 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Events | |
Anomaly | non adherence : published procedure non adherence : clearance other spatial deviation |
Independent Detector | other controllera other flight crewa |
Resolutory Action | flight crew : returned to intended course or assigned course other |
Consequence | Other |
Supplementary | |
Primary Problem | Flight Crew Human Performance |
Air Traffic Incident | Pilot Deviation |
Narrative:
En route V499 ZNY (frequency unknown) gave holding instruction around lrp VOR, cleared direct skills, hold at skills as published right turns, 1.5 NM legs. Efc XXXX. I put in direct skils and slowed to the recommended hold speed (211 KTS). The aircraft was in navigation mode and turned right direct skils (212 degree heading). I pulled up the hold page and it showed the correct hold information. I put in the efc time. As the aircraft slowed, ZNY switched us to 135.45 (ZNY). A short time after checking in center said that we were 3-4 NM left of course, please turn right to re-intercept. I told the captain that the previous controller had cleared us direct skils, so what course did he mean. The captain looked at the low altitude chart and put in balance 012 degree right (V93), which was our original routing. The ADI showed us left of V93 (approximately 2-1 1/2 dots). The captain did not inform ZNY of our previous clearance. Then I turned the aircraft 20-25 degrees right (on heading select mode) to intercept V93 to skils. I mentioned to the captain again that the previous controller had cleared us direct, not V93, but he chose not to tell ZNY. At skils, I put the aircraft on LNAV to begin the holding pattern and it began a left turn, incorrectly. I went to heading select immediate and turned right as published. Since we were inbound on V93 it should have made a right to enter holding. The captain suggested we time 30 seconds outbnd and started the time. This hold depicts a 2 NM leg (low altitude chart). But 15-20 seconds later we were 22 DME and I began the right turn inbound. We were left of course so I corrected 30 degrees to the right (approximately 2 DOT deflection). As the turn completed DME showed 25.6. ZNY called and told us to 'keep it tight' as there were other aircraft holding to our left (at trish we thought). At 20 DME I turned right and correct 20 degrees to the left. The captain suggested we turn earlier than 21.5 DME. I turned inbound at 20.9 DME, which was 15-20 seconds after wings level. On rollout inbound, the DME read 23.8. Again a sizeable correction to the right was required, -35 degrees. In less than 20 seconds the DME showed 20.9 and I again turned outbnd. I tried LNAV for holding in 2 of the turns, but the aircraft attempted to roll wings level (perhaps to turn left) both times. I again checked the hold page and all information was correct. This problem with the computer no doubt made a ridiculously published holding pattern much more difficult to fly. But even if the computer had flown this hold correctly there is not doubt that the aircraft would have been rolling in and out of 30 degree banks continuously. We held approximately 20 mins and made approximately 8 patterns. The addition of strong xwinds, 211 KTS, and numerous aircraft holding downwind at trish made this situation, in my opinion, an absurd one. This crew did its best, given the circumstances. The published hold at skils should not be used for turbo jet aircraft. Also, it is not conducive to passenger comfort to be in a 30 degree bank every 15-20 seconds. Callback conversation with reporter revealed the following: reporter answered questions candidly. She explained how the computer works on the airplane. When asked if forcing the aircraft to turn too soon in the holding pattern could cause it to react as her's did, she said that she thought it could. She reiterated that she was sure that they were cleared to hold with a 1 1/2 mi pattern at skils. She went on to tell of various computer glitches that occur and baffle all users.
Original NASA ASRS Text
Title: REPORTER COULD NOT MANAGE TO KEEP HER ACFT WITHIN THE CONFINES OF THE HOLDING PATTERN.
Narrative: ENRTE V499 ZNY (FREQ UNKNOWN) GAVE HOLDING INSTRUCTION AROUND LRP VOR, CLRED DIRECT SKILLS, HOLD AT SKILLS AS PUBLISHED RIGHT TURNS, 1.5 NM LEGS. EFC XXXX. I PUT IN DIRECT SKILS AND SLOWED TO THE RECOMMENDED HOLD SPD (211 KTS). THE ACFT WAS IN NAV MODE AND TURNED RIGHT DIRECT SKILS (212 DEG HDG). I PULLED UP THE HOLD PAGE AND IT SHOWED THE CORRECT HOLD INFO. I PUT IN THE EFC TIME. AS THE ACFT SLOWED, ZNY SWITCHED US TO 135.45 (ZNY). A SHORT TIME AFTER CHKING IN CENTER SAID THAT WE WERE 3-4 NM LEFT OF COURSE, PLEASE TURN RIGHT TO RE-INTERCEPT. I TOLD THE CAPT THAT THE PREVIOUS CTLR HAD CLRED US DIRECT SKILS, SO WHAT COURSE DID HE MEAN. THE CAPT LOOKED AT THE LOW ALT CHART AND PUT IN BAL 012 DEG R (V93), WHICH WAS OUR ORIGINAL ROUTING. THE ADI SHOWED US LEFT OF V93 (APPROX 2-1 1/2 DOTS). THE CAPT DID NOT INFORM ZNY OF OUR PREVIOUS CLRNC. THEN I TURNED THE ACFT 20-25 DEGS RIGHT (ON HDG SELECT MODE) TO INTERCEPT V93 TO SKILS. I MENTIONED TO THE CAPT AGAIN THAT THE PREVIOUS CTLR HAD CLRED US DIRECT, NOT V93, BUT HE CHOSE NOT TO TELL ZNY. AT SKILS, I PUT THE ACFT ON LNAV TO BEGIN THE HOLDING PATTERN AND IT BEGAN A LEFT TURN, INCORRECTLY. I WENT TO HDG SELECT IMMEDIATE AND TURNED RIGHT AS PUBLISHED. SINCE WE WERE INBND ON V93 IT SHOULD HAVE MADE A RIGHT TO ENTER HOLDING. THE CAPT SUGGESTED WE TIME 30 SECS OUTBND AND STARTED THE TIME. THIS HOLD DEPICTS A 2 NM LEG (LOW ALT CHART). BUT 15-20 SECS LATER WE WERE 22 DME AND I BEGAN THE RIGHT TURN INBND. WE WERE LEFT OF COURSE SO I CORRECTED 30 DEGS TO THE RIGHT (APPROX 2 DOT DEFLECTION). AS THE TURN COMPLETED DME SHOWED 25.6. ZNY CALLED AND TOLD US TO 'KEEP IT TIGHT' AS THERE WERE OTHER ACFT HOLDING TO OUR LEFT (AT TRISH WE THOUGHT). AT 20 DME I TURNED RIGHT AND CORRECT 20 DEGS TO THE LEFT. THE CAPT SUGGESTED WE TURN EARLIER THAN 21.5 DME. I TURNED INBND AT 20.9 DME, WHICH WAS 15-20 SECS AFTER WINGS LEVEL. ON ROLLOUT INBND, THE DME READ 23.8. AGAIN A SIZEABLE CORRECTION TO THE RIGHT WAS REQUIRED, -35 DEGS. IN LESS THAN 20 SECS THE DME SHOWED 20.9 AND I AGAIN TURNED OUTBND. I TRIED LNAV FOR HOLDING IN 2 OF THE TURNS, BUT THE ACFT ATTEMPTED TO ROLL WINGS LEVEL (PERHAPS TO TURN LEFT) BOTH TIMES. I AGAIN CHKED THE HOLD PAGE AND ALL INFO WAS CORRECT. THIS PROB WITH THE COMPUTER NO DOUBT MADE A RIDICULOUSLY PUBLISHED HOLDING PATTERN MUCH MORE DIFFICULT TO FLY. BUT EVEN IF THE COMPUTER HAD FLOWN THIS HOLD CORRECTLY THERE IS NOT DOUBT THAT THE ACFT WOULD HAVE BEEN ROLLING IN AND OUT OF 30 DEG BANKS CONTINUOUSLY. WE HELD APPROX 20 MINS AND MADE APPROX 8 PATTERNS. THE ADDITION OF STRONG XWINDS, 211 KTS, AND NUMEROUS ACFT HOLDING DOWNWIND AT TRISH MADE THIS SITUATION, IN MY OPINION, AN ABSURD ONE. THIS CREW DID ITS BEST, GIVEN THE CIRCUMSTANCES. THE PUBLISHED HOLD AT SKILS SHOULD NOT BE USED FOR TURBO JET ACFT. ALSO, IT IS NOT CONDUCIVE TO PAX COMFORT TO BE IN A 30 DEG BANK EVERY 15-20 SECS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR ANSWERED QUESTIONS CANDIDLY. SHE EXPLAINED HOW THE COMPUTER WORKS ON THE AIRPLANE. WHEN ASKED IF FORCING THE ACFT TO TURN TOO SOON IN THE HOLDING PATTERN COULD CAUSE IT TO REACT AS HER'S DID, SHE SAID THAT SHE THOUGHT IT COULD. SHE REITERATED THAT SHE WAS SURE THAT THEY WERE CLRED TO HOLD WITH A 1 1/2 MI PATTERN AT SKILS. SHE WENT ON TO TELL OF VARIOUS COMPUTER GLITCHES THAT OCCUR AND BAFFLE ALL USERS.
Data retrieved from NASA's ASRS site as of August 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.