Air carrier medium large transport track heading deviation en route to isp.

Attributes
ACN	197537
Time
Date	199112
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : hto
State Reference	NY
Altitude	msl bound lower : 11000 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other descent other
Route In Use	enroute : direct enroute airway : j121
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 7300 flight time type : 2400
ASRS Report	197537
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Our clearance was to an intersection on J121 southwest of pvd 32 mi then direct to calverton VOR. I misread the high altitude chart by reading the DME to a different intersection located very close to the one we were navigating to. We made our turn direct to calverton VOR at about 36 mi over the mistaken intersection mileage, rather than 32 mi. Approach control gave us a heading moments later to 360 degree, no mention of our slightly early turn. The new york high altitude chart is good and usually easy to read but this intersection mileage confusion was very easy happen. The chart should be revised to have the mileage located closer to the intxns. The same map has other airways very poorly labeled for the radials.

Original NASA ASRS Text

Title: ACR MLG TRACK HDG DEV ENRTE TO ISP.

Narrative: OUR CLRNC WAS TO AN INTXN ON J121 SW OF PVD 32 MI THEN DIRECT TO CALVERTON VOR. I MISREAD THE HIGH ALT CHART BY READING THE DME TO A DIFFERENT INTXN LOCATED VERY CLOSE TO THE ONE WE WERE NAVIGATING TO. WE MADE OUR TURN DIRECT TO CALVERTON VOR AT ABOUT 36 MI OVER THE MISTAKEN INTXN MILEAGE, RATHER THAN 32 MI. APCH CTL GAVE US A HDG MOMENTS LATER TO 360 DEG, NO MENTION OF OUR SLIGHTLY EARLY TURN. THE NEW YORK HIGH ALT CHART IS GOOD AND USUALLY EASY TO READ BUT THIS INTXN MILEAGE CONFUSION WAS VERY EASY HAPPEN. THE CHART SHOULD BE REVISED TO HAVE THE MILEAGE LOCATED CLOSER TO THE INTXNS. THE SAME MAP HAS OTHER AIRWAYS VERY POORLY LABELED FOR THE RADIALS.

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.