Route deviation on the CLN6B departure from london using FMS for navigation.

Attributes
ACN	479817
Time
Date	200007
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : egtt.artcc
State Reference	FO
Altitude	msl single value : 15000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ewr.tower
Operator	general aviation : personal
Make Model Name	Gulfstream II
Operating Under FAR Part	Part 91
Navigation In Use	other
Route In Use	departure sid : clngb
Flight Plan	IFR
Person 1
Qualification	pilot : multi engine pilot : commercial pilot : instrument
Experience	flight time total : 6200
ASRS Report	479817
Person 2
Affiliation	other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 60 flight time total : 12000 flight time type : 3000
ASRS Report	480275
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance other spatial deviation
Independent Detector	atc equipment : conflict alert aircraft equipment other aircraft equipment : vhf.nav other controllerb other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to original clearance
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

After programming our aircraft FMS for a flight from london (eggw) to amsterdam (eham), verifying the navigation fixes and coordinates for the assigned departure and route, we experienced a navigation difficulty. During the departure, both FMS navigation controls pointed our aircraft towards a stray navigation fix, detling (det) VOR which was not programmed by us or part of the SID clacton 6B (CLN6B) our assigned departure. Once the wrong turn was initialized, we realized the mistake through backup from ground based navigation system. London ATC promptly recognized the error simultaneously and vectored us back on the departure to our first en route fix. The problem existed somewhere within the universal FMS navigation system or its database. Though we have not been able to duplicate, or have experienced a similar problem elsewhere.

Original NASA ASRS Text

Title: RTE DEV ON THE CLN6B DEP FROM LONDON USING FMS FOR NAV.

Narrative: AFTER PROGRAMMING OUR ACFT FMS FOR A FLT FROM LONDON (EGGW) TO AMSTERDAM (EHAM), VERIFYING THE NAV FIXES AND COORDINATES FOR THE ASSIGNED DEP AND RTE, WE EXPERIENCED A NAV DIFFICULTY. DURING THE DEP, BOTH FMS NAV CTLS POINTED OUR ACFT TOWARDS A STRAY NAV FIX, DETLING (DET) VOR WHICH WAS NOT PROGRAMMED BY US OR PART OF THE SID CLACTON 6B (CLN6B) OUR ASSIGNED DEP. ONCE THE WRONG TURN WAS INITIALIZED, WE REALIZED THE MISTAKE THROUGH BACKUP FROM GND BASED NAV SYS. LONDON ATC PROMPTLY RECOGNIZED THE ERROR SIMULTANEOUSLY AND VECTORED US BACK ON THE DEP TO OUR FIRST ENRTE FIX. THE PROB EXISTED SOMEWHERE WITHIN THE UNIVERSAL FMS NAV SYS OR ITS DATABASE. THOUGH WE HAVE NOT BEEN ABLE TO DUPLICATE, OR HAVE EXPERIENCED A SIMILAR PROB ELSEWHERE.

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.