 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
An air carrier DC9 flight crew crossed the ltown fix too high when they misrefed the DME distance to to the fix.
| Attributes | |
| ACN | 376260 |
| Time | |
| Date | 199707 |
| Day | Thu |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : mem |
| State Reference | TN |
| Altitude | msl bound lower : 12000 msl bound upper : 14000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : mem tower : elm |
| Operator | common carrier : air carrier |
| Make Model Name | DC-9 30 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent other |
| Route In Use | arrival other arrival star : star |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 175 flight time total : 6500 flight time type : 800 |
| ASRS Report | 376260 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 200 flight time total : 17500 flight time type : 8000 |
| ASRS Report | 375999 |
| Events | |
| Anomaly | altitude deviation : undershoot altitude deviation : crossing restriction not met non adherence : clearance non adherence : far |
| Independent Detector | other controllera |
| Resolutory Action | flight crew : returned to intended course or assigned course other |
| Consequence | faa : reviewed incident with flight crew |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
After numerous ATC directed dscnts and heading changes, the air carrier flight was cleared to cross ltown intersection, on wilder 1 arrival to mem, at 14000 ft and 250 KTS. Ltown DME is 40 DME. As PF, I earlier planned to ask for/start descent to cross ltown at 12000 ft and 250 KTS. Numerous altitude/heading changes and busy cockpit procedures, when coupled with erroneous DME for ltown verbally stated by captain, caused me to mentally reset descent planning to cross ltown at 20 DME vice 40 DME. This error reinforced by heavy ATC directions /radio communications. Newness of wilder 1 arrival usage. Captain's statement that 'ltown was 20 DME.' '20 DME' written on wilder 1 arrival chart at ltown intersection. This is segment DME from last intersection closer to mem and not actual total DME to ltown (40 DME). All above resulted in PNF to make erroneous verbal call of ltown DME which in busy ATC environment allowed PF to mentally 'reset' ltown to wrong DME resulting in crossing ltown at wrong altitude and airspeed. PNF was in error, but as captain, may have inadvertently influenced PF by fact that he's captain and unconsciously 'must be right.' he wasn't, and we failed to meet ATC restrs. No ATC problems encountered per later phone conversation with mem approach controllers.
Original NASA ASRS Text
Title: AN ACR DC9 FLC CROSSED THE LTOWN FIX TOO HIGH WHEN THEY MISREFED THE DME DISTANCE TO TO THE FIX.
Narrative: AFTER NUMEROUS ATC DIRECTED DSCNTS AND HDG CHANGES, THE ACR FLT WAS CLRED TO CROSS LTOWN INTXN, ON WILDER 1 ARR TO MEM, AT 14000 FT AND 250 KTS. LTOWN DME IS 40 DME. AS PF, I EARLIER PLANNED TO ASK FOR/START DSCNT TO CROSS LTOWN AT 12000 FT AND 250 KTS. NUMEROUS ALT/HDG CHANGES AND BUSY COCKPIT PROCS, WHEN COUPLED WITH ERRONEOUS DME FOR LTOWN VERBALLY STATED BY CAPT, CAUSED ME TO MENTALLY RESET DSCNT PLANNING TO CROSS LTOWN AT 20 DME VICE 40 DME. THIS ERROR REINFORCED BY HVY ATC DIRECTIONS /RADIO COMS. NEWNESS OF WILDER 1 ARR USAGE. CAPT'S STATEMENT THAT 'LTOWN WAS 20 DME.' '20 DME' WRITTEN ON WILDER 1 ARR CHART AT LTOWN INTXN. THIS IS SEGMENT DME FROM LAST INTXN CLOSER TO MEM AND NOT ACTUAL TOTAL DME TO LTOWN (40 DME). ALL ABOVE RESULTED IN PNF TO MAKE ERRONEOUS VERBAL CALL OF LTOWN DME WHICH IN BUSY ATC ENVIRONMENT ALLOWED PF TO MENTALLY 'RESET' LTOWN TO WRONG DME RESULTING IN XING LTOWN AT WRONG ALT AND AIRSPD. PNF WAS IN ERROR, BUT AS CAPT, MAY HAVE INADVERTENTLY INFLUENCED PF BY FACT THAT HE'S CAPT AND UNCONSCIOUSLY 'MUST BE RIGHT.' HE WASN'T, AND WE FAILED TO MEET ATC RESTRS. NO ATC PROBS ENCOUNTERED PER LATER PHONE CONVERSATION WITH MEM APCH CTLRS.
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.