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|
Attributes | |
ACN | 200534 |
Time | |
Date | 199201 |
Day | Sun |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | atc facility : zdc |
State Reference | DC |
Altitude | msl bound lower : 24000 msl bound upper : 30000 |
Environment | |
Flight Conditions | Mixed |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zdc |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Navigation In Use | Other Other |
Flight Phase | descent other |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : flight engineer pilot : cfi pilot : atp |
Experience | flight time last 90 days : 70 flight time total : 9000 flight time type : 600 |
ASRS Report | 200534 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : atp |
Events | |
Anomaly | altitude deviation : undershoot altitude deviation : crossing restriction not met non adherence : clearance |
Independent Detector | other flight crewa |
Resolutory Action | none taken : insufficient time |
Consequence | Other |
Supplementary | |
Primary Problem | Flight Crew Human Performance |
Air Traffic Incident | Pilot Deviation |
Narrative:
On flight from msp-dca, position northwest of bucko intersection on J-34 with routing of J-34 to bucko, then bucko three arrival to dca. At cruise at FL370, given clearance to cross 25 mi west of esl at FL240. After initiating descent, determined that crossing restriction would not be made, informed ATC, and were given new altitude restriction further east. Contributing factors to this inability to make the crossing restriction were: 1. Had completed about 1/2 of the 'encon' data for this leg (that is cruise engine parameters which we record in our aircraft logbook for maintenance tracking). The aircraft is required to be in level flight with autothrust off and engines stabilized while we record this data. We opted to finish this recording before beginning our descent which consumed 1-2 mins additional time. 2. Strong tailwinds. 3. 'Clean' nature of our aircraft and resultant slower rates of descent at normal speeds and configns (as opposed to older types). 4. Automated nature of FMS system. We began our descent which initially was at a slower rate than we desired. After a min or so, we realized that our autothrust system was still disengaged after our 'encon' procedure (2 above) upon re-engagement, normal descent rate was restored. However, we now were behind a descent schedule which would allow us to make our crossing restriction. While this inability to make the crossing restriction was a result of the crew's actions, I want to make two points which contributed to this: 1. The FMS in this airplane often does lead to momentary misunderstanding or questions concerning the programming of the system. We are trained to use the automatic or programmed systems. When the airplane does not immediately respond as the crew intended, the typical response is to ponder what programming steps were done incorrectly, rather than just fly it manually which of course consumes time. 2. Newer generation aircraft do not descend as rapidly in normal configns as do older types.
Original NASA ASRS Text
Title: ALT XING RESTRICTION NOT MADE IN AN ALTDEV ALT UNDERSHOT INCIDENT.
Narrative: ON FLT FROM MSP-DCA, POS NW OF BUCKO INTXN ON J-34 WITH RTING OF J-34 TO BUCKO, THEN BUCKO THREE ARR TO DCA. AT CRUISE AT FL370, GIVEN CLRNC TO CROSS 25 MI W OF ESL AT FL240. AFTER INITIATING DSCNT, DETERMINED THAT XING RESTRICTION WOULD NOT BE MADE, INFORMED ATC, AND WERE GIVEN NEW ALT RESTRICTION FURTHER E. CONTRIBUTING FACTORS TO THIS INABILITY TO MAKE THE XING RESTRICTION WERE: 1. HAD COMPLETED ABOUT 1/2 OF THE 'ENCON' DATA FOR THIS LEG (THAT IS CRUISE ENG PARAMETERS WHICH WE RECORD IN OUR ACFT LOGBOOK FOR MAINT TRACKING). THE ACFT IS REQUIRED TO BE IN LEVEL FLT WITH AUTOTHRUST OFF AND ENGS STABILIZED WHILE WE RECORD THIS DATA. WE OPTED TO FINISH THIS RECORDING BEFORE BEGINNING OUR DSCNT WHICH CONSUMED 1-2 MINS ADDITIONAL TIME. 2. STRONG TAILWINDS. 3. 'CLEAN' NATURE OF OUR ACFT AND RESULTANT SLOWER RATES OF DSCNT AT NORMAL SPDS AND CONFIGNS (AS OPPOSED TO OLDER TYPES). 4. AUTOMATED NATURE OF FMS SYS. WE BEGAN OUR DSCNT WHICH INITIALLY WAS AT A SLOWER RATE THAN WE DESIRED. AFTER A MIN OR SO, WE REALIZED THAT OUR AUTOTHRUST SYS WAS STILL DISENGAGED AFTER OUR 'ENCON' PROC (2 ABOVE) UPON RE-ENGAGEMENT, NORMAL DSCNT RATE WAS RESTORED. HOWEVER, WE NOW WERE BEHIND A DSCNT SCHEDULE WHICH WOULD ALLOW US TO MAKE OUR XING RESTRICTION. WHILE THIS INABILITY TO MAKE THE XING RESTRICTION WAS A RESULT OF THE CREW'S ACTIONS, I WANT TO MAKE TWO POINTS WHICH CONTRIBUTED TO THIS: 1. THE FMS IN THIS AIRPLANE OFTEN DOES LEAD TO MOMENTARY MISUNDERSTANDING OR QUESTIONS CONCERNING THE PROGRAMMING OF THE SYS. WE ARE TRAINED TO USE THE AUTOMATIC OR PROGRAMMED SYSTEMS. WHEN THE AIRPLANE DOES NOT IMMEDIATELY RESPOND AS THE CREW INTENDED, THE TYPICAL RESPONSE IS TO PONDER WHAT PROGRAMMING STEPS WERE DONE INCORRECTLY, RATHER THAN JUST FLY IT MANUALLY WHICH OF COURSE CONSUMES TIME. 2. NEWER GENERATION ACFT DO NOT DSND AS RAPIDLY IN NORMAL CONFIGNS AS DO OLDER TYPES.
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.