Pitch control problem. Foreign object.

Attributes
ACN	102447
Time
Date	198901
Day	Wed
Place
Locale Reference	atc facility : lgb
State Reference	CA
Altitude	msl bound lower : 0 msl bound upper : 18000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla
Operator	general aviation : corporate
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	climbout : takeoff cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 35 flight time total : 665 flight time type : 175
ASRS Report	102447
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Pitch control difficulty noticed on takeoff from lgb. Still having problems passing lake hughes VOR, cancelled IFR below 18000' and attempted to diagnose problem. Finally was able to stabilize airplane after pulling autoplt breaker and with power, pitch trim was able to get altitude to stop fluctuating. Although the altitude continued to fluctuate, I continued VFR with advisories from center (ZLA, then ZOA). Descent was long and slow and pitch control improved to normal during the descent. Upon disassembly of the airplane, a blanket was found in tail section which had apparently wedged in the autoplt actuator causing shearing of shaft and elevator binding. Removal of blanket and repair of actuator made everything normal again. Only suggestion I have for prevention of this type of hazard is procedural, where no mechanic closes up an airplane's covers unless another pair of eyes examine the area to be closed.

Original NASA ASRS Text

Title: PITCH CONTROL PROBLEM. FOREIGN OBJECT.

Narrative: PITCH CONTROL DIFFICULTY NOTICED ON TKOF FROM LGB. STILL HAVING PROBS PASSING LAKE HUGHES VOR, CANCELLED IFR BELOW 18000' AND ATTEMPTED TO DIAGNOSE PROB. FINALLY WAS ABLE TO STABILIZE AIRPLANE AFTER PULLING AUTOPLT BREAKER AND WITH PWR, PITCH TRIM WAS ABLE TO GET ALT TO STOP FLUCTUATING. ALTHOUGH THE ALT CONTINUED TO FLUCTUATE, I CONTINUED VFR WITH ADVISORIES FROM CENTER (ZLA, THEN ZOA). DSCNT WAS LONG AND SLOW AND PITCH CONTROL IMPROVED TO NORMAL DURING THE DSCNT. UPON DISASSEMBLY OF THE AIRPLANE, A BLANKET WAS FOUND IN TAIL SECTION WHICH HAD APPARENTLY WEDGED IN THE AUTOPLT ACTUATOR CAUSING SHEARING OF SHAFT AND ELEVATOR BINDING. REMOVAL OF BLANKET AND REPAIR OF ACTUATOR MADE EVERYTHING NORMAL AGAIN. ONLY SUGGESTION I HAVE FOR PREVENTION OF THIS TYPE OF HAZARD IS PROCEDURAL, WHERE NO MECH CLOSES UP AN AIRPLANE'S COVERS UNLESS ANOTHER PAIR OF EYES EXAMINE THE AREA TO BE CLOSED.

Data retrieved from NASA's ASRS site as of August 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.