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Deviation from route and clearance when PIC of B737 tunes in wrong VOR and proceeds direct. Failed to identify frequency and blames liquid crystal display units for poor design and impaired readouts.
| Attributes | |
| ACN | 362818 |
| Time | |
| Date | 199703 |
| Day | Tue |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | atc facility : cqy |
| State Reference | TX |
| Altitude | msl bound lower : 10000 msl bound upper : 10000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | tracon : dfw |
| Operator | common carrier : air carrier |
| Make Model Name | B737 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise other descent other |
| Route In Use | arrival other arrival star : star enroute : direct |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp pilot : cfi pilot : flight engineer |
| Experience | flight time last 90 days : 200 flight time total : 15500 flight time type : 12000 |
| ASRS Report | 362818 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : commercial pilot : instrument |
| Events | |
| Anomaly | aircraft equipment problem : less severe non adherence : clearance non adherence other other anomaly other other spatial deviation |
| Independent Detector | other controllera |
| Resolutory Action | controller : issued new clearance other |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation other |
Narrative:
Cleared direct cedar creek VOR (114.8). Had bonham VOR (114.6) tuned in error. Our VOR tuner readouts are liquid crystal display unit displays which are fine when new, but with age, wear and tear, etc, become hard to read. After discovering our error (thanks to ATC) it was still hard to tell the .6 from a .8 on the liquid crystal display. This problem is made worse by partial failure of the back-lighting (a common occurrence), damage to the display unit due to poor design and placement (placing a non sealed liquid crystal display unit on a horizontal pedestal where it is subject to use as a 'table' and frequent liquid spills). In this case, 2 arrival vors are placed almost in-line on the STAR and only about 20 mi apart -- also the displayed frequencys appear similar, especially with degraded displays.
Original NASA ASRS Text
Title: DEV FROM RTE AND CLRNC WHEN PIC OF B737 TUNES IN WRONG VOR AND PROCEEDS DIRECT. FAILED TO IDENT FREQ AND BLAMES LIQUID CRYSTAL DISPLAY UNITS FOR POOR DESIGN AND IMPAIRED READOUTS.
Narrative: CLRED DIRECT CEDAR CREEK VOR (114.8). HAD BONHAM VOR (114.6) TUNED IN ERROR. OUR VOR TUNER READOUTS ARE LIQUID CRYSTAL DISPLAY UNIT DISPLAYS WHICH ARE FINE WHEN NEW, BUT WITH AGE, WEAR AND TEAR, ETC, BECOME HARD TO READ. AFTER DISCOVERING OUR ERROR (THANKS TO ATC) IT WAS STILL HARD TO TELL THE .6 FROM A .8 ON THE LIQUID CRYSTAL DISPLAY. THIS PROB IS MADE WORSE BY PARTIAL FAILURE OF THE BACK-LIGHTING (A COMMON OCCURRENCE), DAMAGE TO THE DISPLAY UNIT DUE TO POOR DESIGN AND PLACEMENT (PLACING A NON SEALED LIQUID CRYSTAL DISPLAY UNIT ON A HORIZ PEDESTAL WHERE IT IS SUBJECT TO USE AS A 'TABLE' AND FREQUENT LIQUID SPILLS). IN THIS CASE, 2 ARR VORS ARE PLACED ALMOST IN-LINE ON THE STAR AND ONLY ABOUT 20 MI APART -- ALSO THE DISPLAYED FREQS APPEAR SIMILAR, ESPECIALLY WITH DEGRADED DISPLAYS.
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.