Flight crew of a B727-200 had an uncommanded flap slat partial extension during descent turbulence.

Attributes
ACN	274798
Time
Date	199406
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : ape airport : cvg
State Reference	OH
Altitude	msl bound lower : 19000 msl bound upper : 19000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 10000 flight time type : 6000
ASRS Report	274798
Person 2
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : private pilot : instrument pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time total : 3500
ASRS Report	274797
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

The flaps and leading edge devices started to deploy with no pilot initiation. The flap handle was out of the detent and in a slightly deployed position. Quick action by the first officer at the controls stowed the flap handle to the up detent. We believe the choppy light turbulence and incorrect flap handle rigging caused the flap handle to work its way out of the detent and into a slightly deployed position. Supplemental information from acn 274797: we noticed that the flap handle had a spring tension to up and aft which made it very easy to lower the flaps but harder to raise them. Fortunately for us we were at an altitude and airspeed where this wasn't much of a problem but at higher altitudes this could be potentially very dangerous. We suspected that it could have been a rigging problem coupled with turbulence that caused the flap lever to 'pop' out of the 'up' detent.

Original NASA ASRS Text

Title: FLC OF A B727-200 HAD AN UNCOMMANDED FLAP SLAT PARTIAL EXTENSION DURING DSCNT TURB.

Narrative: THE FLAPS AND LEADING EDGE DEVICES STARTED TO DEPLOY WITH NO PLT INITIATION. THE FLAP HANDLE WAS OUT OF THE DETENT AND IN A SLIGHTLY DEPLOYED POS. QUICK ACTION BY THE FO AT THE CTLS STOWED THE FLAP HANDLE TO THE UP DETENT. WE BELIEVE THE CHOPPY LIGHT TURB AND INCORRECT FLAP HANDLE RIGGING CAUSED THE FLAP HANDLE TO WORK ITS WAY OUT OF THE DETENT AND INTO A SLIGHTLY DEPLOYED POS. SUPPLEMENTAL INFO FROM ACN 274797: WE NOTICED THAT THE FLAP HANDLE HAD A SPRING TENSION TO UP AND AFT WHICH MADE IT VERY EASY TO LOWER THE FLAPS BUT HARDER TO RAISE THEM. FORTUNATELY FOR US WE WERE AT AN ALT AND AIRSPD WHERE THIS WASN'T MUCH OF A PROB BUT AT HIGHER ALTS THIS COULD BE POTENTIALLY VERY DANGEROUS. WE SUSPECTED THAT IT COULD HAVE BEEN A RIGGING PROB COUPLED WITH TURB THAT CAUSED THE FLAP LEVER TO 'POP' OUT OF THE 'UP' DETENT.

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.