Small aircraft unable to get normal gear downlock indication does fuel burnoff while troubleshooting...

Attributes
ACN	153976
Time
Date	199008
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : toa
State Reference	CA
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sna tracon : lax tower : toa tower : agc
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	landing other other other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 35 flight time total : 1787 flight time type : 1450
ASRS Report	153976
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	aircraft : equipment problem dissipated controller : provided flight assist flight crew : declared emergency
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

Following normal preflight, I departed toa on IFR plan to smo. After 30 mins of vectoring by la approach due to traffic saturation at smo, I was cleared for VOR-a approach to smo. At bevey I selected gear down. Although left main and nose down lock indication were normal, right main indicator remained off. I reported gear problem to smo tower and pulled up to 2500' to remain in VMC, then orbited smo for 5 mins while attempting to cycle gear. Selecting gear up resulted in no change, neither did emergency gear down procedure (hydraulic pressure dump valve). Cycled circuit breaker's for gear motor and indicator--no results. Activated 'press to test' on right main indicator lamp; lamp was ok. I requested vectors to limbo intersection for holding and received handoff to lax approach. Upon entering limbo, I cancelled IFR (in VMC) and advised intention to proceed VFR to paddr intersection for VFR holding to go through the gear procedures thoroughly, and burn fuel. On handoff to coast approach, I advised the problem and reported 2+ hours of fuel that I intended to burn off prior to landing at toa. Also advised that I would give 15 mins notice prior to land attempt at toa to get crash equipment in position. During the subsequent 1 1/2 hours, coast and toa assisted in 2 low passes by toa tower for gear checks. Toa reported right main appeared to be slightly canted inboard compared to left main. Coast also vectored a twin to rendezvous near paddr for a visibility check. The pilots reported gear appeared down and locked, normal, no hydraulic fluid. Upon reaching my planned fuel remaining of 15 gals (approximately 1 hour at cruise), I conducted a normal approach and landing at toa. Landing was normal. Gear was actually down and locked, although right main indicator remained off. Mechanic found open circuit at ground lug for a wire common to right downlock switch and squat (air/ground strut compression) switch. Wire was visually ok, but broke off with a moderate pull. Wiring and ground lugs were replaced, aircraft jacked and normal gear operation recorded in log book.

Original NASA ASRS Text

Title: SMA UNABLE TO GET NORMAL GEAR DOWNLOCK INDICATION DOES FUEL BURNOFF WHILE TROUBLESHOOTING WITH ASSISTANCE FROM ATC AND CHASE PLANE OBSERVER AND MAKES NORMAL LNDG.

Narrative: FOLLOWING NORMAL PREFLT, I DEPARTED TOA ON IFR PLAN TO SMO. AFTER 30 MINS OF VECTORING BY LA APCH DUE TO TFC SATURATION AT SMO, I WAS CLRED FOR VOR-A APCH TO SMO. AT BEVEY I SELECTED GEAR DOWN. ALTHOUGH LEFT MAIN AND NOSE DOWN LOCK INDICATION WERE NORMAL, RIGHT MAIN INDICATOR REMAINED OFF. I RPTED GEAR PROB TO SMO TWR AND PULLED UP TO 2500' TO REMAIN IN VMC, THEN ORBITED SMO FOR 5 MINS WHILE ATTEMPTING TO CYCLE GEAR. SELECTING GEAR UP RESULTED IN NO CHANGE, NEITHER DID EMER GEAR DOWN PROC (HYD PRESSURE DUMP VALVE). CYCLED CB'S FOR GEAR MOTOR AND INDICATOR--NO RESULTS. ACTIVATED 'PRESS TO TEST' ON RIGHT MAIN INDICATOR LAMP; LAMP WAS OK. I REQUESTED VECTORS TO LIMBO INTXN FOR HOLDING AND RECEIVED HDOF TO LAX APCH. UPON ENTERING LIMBO, I CANCELLED IFR (IN VMC) AND ADVISED INTENTION TO PROCEED VFR TO PADDR INTXN FOR VFR HOLDING TO GO THROUGH THE GEAR PROCS THOROUGHLY, AND BURN FUEL. ON HDOF TO COAST APCH, I ADVISED THE PROB AND RPTED 2+ HRS OF FUEL THAT I INTENDED TO BURN OFF PRIOR TO LNDG AT TOA. ALSO ADVISED THAT I WOULD GIVE 15 MINS NOTICE PRIOR TO LAND ATTEMPT AT TOA TO GET CRASH EQUIP IN POS. DURING THE SUBSEQUENT 1 1/2 HRS, COAST AND TOA ASSISTED IN 2 LOW PASSES BY TOA TWR FOR GEAR CHKS. TOA RPTED RIGHT MAIN APPEARED TO BE SLIGHTLY CANTED INBOARD COMPARED TO LEFT MAIN. COAST ALSO VECTORED A TWIN TO RENDEZVOUS NEAR PADDR FOR A VIS CHK. THE PLTS RPTED GEAR APPEARED DOWN AND LOCKED, NORMAL, NO HYD FLUID. UPON REACHING MY PLANNED FUEL REMAINING OF 15 GALS (APPROX 1 HR AT CRUISE), I CONDUCTED A NORMAL APCH AND LNDG AT TOA. LNDG WAS NORMAL. GEAR WAS ACTUALLY DOWN AND LOCKED, ALTHOUGH RIGHT MAIN INDICATOR REMAINED OFF. MECH FOUND OPEN CIRCUIT AT GND LUG FOR A WIRE COMMON TO RIGHT DOWNLOCK SWITCH AND SQUAT (AIR/GND STRUT COMPRESSION) SWITCH. WIRE WAS VISUALLY OK, BUT BROKE OFF WITH A MODERATE PULL. WIRING AND GND LUGS WERE REPLACED, ACFT JACKED AND NORMAL GEAR OPERATION RECORDED IN LOG BOOK.

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.

Small aircraft unable to get normal gear downlock indication does fuel burnoff while troubleshooting with assistance from ATC and chase plane observer and makes normal landing.