A B727 PIC turns too soon towards aml on the arrival to dca north of mrb, wv.

Attributes
ACN	457570
Time
Date	199912
Day	Thu
Local Time Of Day	1201 To 1800
Place
State Reference	WV
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dca.tracon
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : intermediate altitude
Route In Use	enroute airway : v143.airway
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument pilot : flight engineer
Experience	flight time last 90 days : 180 flight time total : 7000 flight time type : 4000
ASRS Report	457570
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 130 flight time total : 21000 flight time type : 5000
ASRS Report	457569
Events
Anomaly	non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued advisory controller : issued new clearance
Supplementary
Problem Areas	Chart Or Publication Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Misread the DME for robrt fix on V143. Started turn toward aml 6 mi too soon. ATC called and advised we turned early and gave us a vector to aml (armel) VOR. No conflict with other traffic took place. Remainder of flight was uneventful. Rechk charts and verify with other crew members on DME fixes and courses. That should have prevented the mistake. Supplemental information from acn 457569: this problem was caused by my misreading the chart. A strange area and too much information crammed onto the chart helped me in my problem of misreading the chart. I will look very carefully at my crossing points in the future.

Original NASA ASRS Text

Title: A B727 PIC TURNS TOO SOON TOWARDS AML ON THE ARR TO DCA N OF MRB, WV.

Narrative: MISREAD THE DME FOR ROBRT FIX ON V143. STARTED TURN TOWARD AML 6 MI TOO SOON. ATC CALLED AND ADVISED WE TURNED EARLY AND GAVE US A VECTOR TO AML (ARMEL) VOR. NO CONFLICT WITH OTHER TFC TOOK PLACE. REMAINDER OF FLT WAS UNEVENTFUL. RECHK CHARTS AND VERIFY WITH OTHER CREW MEMBERS ON DME FIXES AND COURSES. THAT SHOULD HAVE PREVENTED THE MISTAKE. SUPPLEMENTAL INFO FROM ACN 457569: THIS PROB WAS CAUSED BY MY MISREADING THE CHART. A STRANGE AREA AND TOO MUCH INFO CRAMMED ONTO THE CHART HELPED ME IN MY PROB OF MISREADING THE CHART. I WILL LOOK VERY CAREFULLY AT MY XING POINTS IN THE FUTURE.

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.