An small aircraft twin flight instructor had an aircraft equipment problem ground wire to the right ...

Attributes
ACN	353515
Time
Date	199611
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : cdw
State Reference	NJ
Altitude	msl bound lower : 2500 msl bound upper : 2500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : cdw
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	other other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot instruction : instructor
Qualification	pilot : instrument pilot : cfi pilot : commercial
Experience	flight time last 90 days : 82 flight time total : 683 flight time type : 34
ASRS Report	353515
Person 2
Affiliation	Other
Function	flight crew : single pilot instruction : trainee
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

My student and I were practicing lndgs at 4n1. When I put the gear down on downwind, we did not receive a right main down and locked light. The gear was recycled with no change. We then switched the right main light bulb with the left. The bulb worked in the left gear position. We then read through the checklist for emergency gear extension. After following the procedures, no right main gear light down was received. My student and I then briefed each other on our intention to contact cdw and have the fire trucks awaiting our arrival. We discussed landing on the left main first and holding the right main off as long as possible. We also discussed just before touchdown we would ajar the cabin door and turn off all electric equipment. After we both felt comfortable with our procedures, we did a low fly-by. The tower told us it appeared our right main was down and locked. When tower informed us that the trucks were positioned, we made an approach. Tower again informed us our gear appeared down. We landed without incident. Although this situation had happened 2 days prior, we felt we had to treat the situation as though it was the first time. The ground wire to the down lock switch was discovered to have been pulled out. The wire was replaced and the correction entered in the logbook and the airplane flown back to home base. The problem from the previous incident was another down wire having been pulled out which was fixed and signed off before this flight.

Original NASA ASRS Text

Title: AN SMA TWIN FLT INSTRUCTOR HAD AN ACFT EQUIP PROB GND WIRE TO THE R MAIN GEAR DOWN LOCK SWITCH PULLED OUT SHOWING THE R MAIN GEAR NOT TO BE DOWN. THE LNDG GEAR WAS LOCKED DOWN AND THE ACFT LANDED SAFELY.

Narrative: MY STUDENT AND I WERE PRACTICING LNDGS AT 4N1. WHEN I PUT THE GEAR DOWN ON DOWNWIND, WE DID NOT RECEIVE A R MAIN DOWN AND LOCKED LIGHT. THE GEAR WAS RECYCLED WITH NO CHANGE. WE THEN SWITCHED THE R MAIN LIGHT BULB WITH THE L. THE BULB WORKED IN THE L GEAR POS. WE THEN READ THROUGH THE CHKLIST FOR EMER GEAR EXTENSION. AFTER FOLLOWING THE PROCS, NO R MAIN GEAR LIGHT DOWN WAS RECEIVED. MY STUDENT AND I THEN BRIEFED EACH OTHER ON OUR INTENTION TO CONTACT CDW AND HAVE THE FIRE TRUCKS AWAITING OUR ARR. WE DISCUSSED LNDG ON THE L MAIN FIRST AND HOLDING THE R MAIN OFF AS LONG AS POSSIBLE. WE ALSO DISCUSSED JUST BEFORE TOUCHDOWN WE WOULD AJAR THE CABIN DOOR AND TURN OFF ALL ELECTRIC EQUIP. AFTER WE BOTH FELT COMFORTABLE WITH OUR PROCS, WE DID A LOW FLY-BY. THE TWR TOLD US IT APPEARED OUR R MAIN WAS DOWN AND LOCKED. WHEN TWR INFORMED US THAT THE TRUCKS WERE POSITIONED, WE MADE AN APCH. TWR AGAIN INFORMED US OUR GEAR APPEARED DOWN. WE LANDED WITHOUT INCIDENT. ALTHOUGH THIS SIT HAD HAPPENED 2 DAYS PRIOR, WE FELT WE HAD TO TREAT THE SIT AS THOUGH IT WAS THE FIRST TIME. THE GND WIRE TO THE DOWN LOCK SWITCH WAS DISCOVERED TO HAVE BEEN PULLED OUT. THE WIRE WAS REPLACED AND THE CORRECTION ENTERED IN THE LOGBOOK AND THE AIRPLANE FLOWN BACK TO HOME BASE. THE PROB FROM THE PREVIOUS INCIDENT WAS ANOTHER DOWN WIRE HAVING BEEN PULLED OUT WHICH WAS FIXED AND SIGNED OFF BEFORE THIS FLT.

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.

An small aircraft twin flight instructor had an aircraft equipment problem ground wire to the right main gear down lock switch pulled out showing the right main gear not to be down. The landing gear was locked down and the aircraft landed safely.