Heading deviation. Misread turn point DME. Chart should be changed to read better.

Attributes
ACN	324116
Time
Date	199512
Day	Fri
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : bos
State Reference	MA
Altitude	msl bound lower : 14000 msl bound upper : 14000
Environment
Flight Conditions	Marginal
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	DC-8 62
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent other
Route In Use	arrival other arrival star : star enroute airway : bos
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 170 flight time total : 17000 flight time type : 400
ASRS Report	324116
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial
Experience	flight time last 90 days : 90 flight time total : 6000 flight time type : 2000
ASRS Report	324096
Events
Anomaly	non adherence : published procedure other anomaly other other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were flying gardner 2 (GDM2) arrival at bos. Late at night the crew was very tired and WX marginal VFR. At 29 DME on gdm 111 degree radial we turned to heading 210 degrees. Approach control asked about heading change. We must have turned early! ATC stated it was ok because there was no traffic. They also stated it happens all the time!! It appears that heading change should be made at 49 mi and not 29 mi. This chart is very confusing and hard to read. At rever a large 49 DME would eliminate this potential problem.

Original NASA ASRS Text

Title: HEADING DEV. MISREAD TURN POINT DME. CHART SHOULD BE CHANGED TO READ BETTER.

Narrative: WE WERE FLYING GARDNER 2 (GDM2) ARR AT BOS. LATE AT NIGHT THE CREW WAS VERY TIRED AND WX MARGINAL VFR. AT 29 DME ON GDM 111 DEG RADIAL WE TURNED TO HDG 210 DEGS. APCH CTL ASKED ABOUT HDG CHANGE. WE MUST HAVE TURNED EARLY! ATC STATED IT WAS OK BECAUSE THERE WAS NO TFC. THEY ALSO STATED IT HAPPENS ALL THE TIME!! IT APPEARS THAT HDG CHANGE SHOULD BE MADE AT 49 MI AND NOT 29 MI. THIS CHART IS VERY CONFUSING AND HARD TO READ. AT REVER A LARGE 49 DME WOULD ELIMINATE THIS POTENTIAL PROB.

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.