Pilot of an small aircraft sel descended below assigned altitude during a STAR due to failure of the...

Attributes
ACN	302195
Time
Date	199504
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ftw
State Reference	TX
Altitude	msl bound lower : 4700 msl bound upper : 5000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ftw
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other descent other
Route In Use	arrival other arrival star : star enroute airway : ftw
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 35 flight time total : 464 flight time type : 113
ASRS Report	302195
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation other

Narrative:

After a 6 hour IFR flight from las-saf to ftw, the autoplt failed in IMC conditions. The speed and rate of descent were too great for the pilot's limited IFR/IMC conditions (10 hour actual). To prevent the problem in the future, the pilot must closely track conditions of flight and use the autoplt as a backup rather than a primary approach in IMC conditions. The autoplt failed due to a loose, not properly secured, power cable.

Original NASA ASRS Text

Title: PLT OF AN SMA SEL DSNDED BELOW ASSIGNED ALT DURING A STAR DUE TO FAILURE OF THE AUTOPLT.

Narrative: AFTER A 6 HR IFR FLT FROM LAS-SAF TO FTW, THE AUTOPLT FAILED IN IMC CONDITIONS. THE SPD AND RATE OF DSCNT WERE TOO GREAT FOR THE PLT'S LIMITED IFR/IMC CONDITIONS (10 HR ACTUAL). TO PREVENT THE PROB IN THE FUTURE, THE PLT MUST CLOSELY TRACK CONDITIONS OF FLT AND USE THE AUTOPLT AS A BACKUP RATHER THAN A PRIMARY APCH IN IMC CONDITIONS. THE AUTOPLT FAILED DUE TO A LOOSE, NOT PROPERLY SECURED, PWR CABLE.

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.

Pilot of an small aircraft sel descended below assigned altitude during a STAR due to failure of the autoplt.