C210 pilot returns for maintenance when gear retraction cycle produces an unusual noise.

Attributes
ACN	807366
Time
Date	200810
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 1200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : zzz.tower tower : zzz.tower
Operator	general aviation : personal
Make Model Name	Cessna 120
Operating Under FAR Part	Part 91
Flight Phase	climbout : initial
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 30 flight time total : 2696 flight time type : 2449
ASRS Report	807366
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa
Resolutory Action	flight crew : overrode automation flight crew : landed as precaution
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

I retracted the landing gear normally after takeoff; and the amber light lit at the end of the cycle; showing that the gear was up and locked. However; I thought that the sound of the gear retracting seemed a little abnormal near the end of the retraction cycle so I decided to stay in the traffic pattern and extend the gear manually as a precautionary measure. The gear extended and locked; the green light appeared; and I landed the airplane without incident. I did not declare an emergency since I had no reason to believe that there was any imminent danger to my passenger; myself or the airplane. I taxied to my tie-down spot and was surprised to see a crash fire rescue equipment vehicle drive up some mins later. I answered the questions about the incident posed by the safety official. I then visually inspected the gear and confirmed that the down locks were fully engaged. I decided to have the landing gear retraction system inspected before using it again; and flew the airplane to a repair facility with the landing gear extended for the short flight. The airplane was put on jacks and the landing gear retracted. During the retraction process; a leak was discovered at a seal in the hydraulic line near the nose gear. The seal was repaired and the landing gear was cycled several times and performed normally.

Original NASA ASRS Text

Title: C210 PLT RETURNS FOR MAINT WHEN GEAR RETRACTION CYCLE PRODUCES AN UNUSUAL NOISE.

Narrative: I RETRACTED THE LNDG GEAR NORMALLY AFTER TKOF; AND THE AMBER LIGHT LIT AT THE END OF THE CYCLE; SHOWING THAT THE GEAR WAS UP AND LOCKED. HOWEVER; I THOUGHT THAT THE SOUND OF THE GEAR RETRACTING SEEMED A LITTLE ABNORMAL NEAR THE END OF THE RETRACTION CYCLE SO I DECIDED TO STAY IN THE TFC PATTERN AND EXTEND THE GEAR MANUALLY AS A PRECAUTIONARY MEASURE. THE GEAR EXTENDED AND LOCKED; THE GREEN LIGHT APPEARED; AND I LANDED THE AIRPLANE WITHOUT INCIDENT. I DID NOT DECLARE AN EMER SINCE I HAD NO REASON TO BELIEVE THAT THERE WAS ANY IMMINENT DANGER TO MY PAX; MYSELF OR THE AIRPLANE. I TAXIED TO MY TIE-DOWN SPOT AND WAS SURPRISED TO SEE A CFR VEHICLE DRIVE UP SOME MINS LATER. I ANSWERED THE QUESTIONS ABOUT THE INCIDENT POSED BY THE SAFETY OFFICIAL. I THEN VISUALLY INSPECTED THE GEAR AND CONFIRMED THAT THE DOWN LOCKS WERE FULLY ENGAGED. I DECIDED TO HAVE THE LNDG GEAR RETRACTION SYS INSPECTED BEFORE USING IT AGAIN; AND FLEW THE AIRPLANE TO A REPAIR FACILITY WITH THE LNDG GEAR EXTENDED FOR THE SHORT FLT. THE AIRPLANE WAS PUT ON JACKS AND THE LNDG GEAR RETRACTED. DURING THE RETRACTION PROCESS; A LEAK WAS DISCOVERED AT A SEAL IN THE HYD LINE NEAR THE NOSE GEAR. THE SEAL WAS REPAIRED AND THE LNDG GEAR WAS CYCLED SEVERAL TIMES AND PERFORMED NORMALLY.

Data retrieved from NASA's ASRS site as of May 2009 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.