Small aircraft has green light but gear not extended. Gear up landing.

Attributes
ACN	233245
Time
Date	199208
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : btv
State Reference	VT
Altitude	agl bound lower : 0 agl bound upper : 2000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : btv
Operator	general aviation : instructional
Make Model Name	Small Aircraft, High Wing, 1 Eng, Retractable Gear
Flight Phase	descent : approach landing other
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial
Experience	flight time last 90 days : 40 flight time total : 6000 flight time type : 100
ASRS Report	233245
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable none taken : detected after the fact
Consequence	other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Gear up landing. The gear handle was down and the green light was on. I assumed the gear was down as normal. Not much damage was done to the plane. Now after rebuilding the plane, we took it up for a test and the gear did not come down. We had to use the hand pump. In rebuilding the plane we did not touch the hydraulic system at all. We did find the relay that changes the pump from gear up to gear down sometimes did not operate normal. There is not much more I can say about this thing that happened. Everything has now been corrected, the plane is flying once more, and it seems to me that it flies better now than before.

Original NASA ASRS Text

Title: SMA HAS GREEN LIGHT BUT GEAR NOT EXTENDED. GEAR UP LNDG.

Narrative: GEAR UP LNDG. THE GEAR HANDLE WAS DOWN AND THE GREEN LIGHT WAS ON. I ASSUMED THE GEAR WAS DOWN AS NORMAL. NOT MUCH DAMAGE WAS DONE TO THE PLANE. NOW AFTER REBUILDING THE PLANE, WE TOOK IT UP FOR A TEST AND THE GEAR DID NOT COME DOWN. WE HAD TO USE THE HAND PUMP. IN REBUILDING THE PLANE WE DID NOT TOUCH THE HYD SYS AT ALL. WE DID FIND THE RELAY THAT CHANGES THE PUMP FROM GEAR UP TO GEAR DOWN SOMETIMES DID NOT OPERATE NORMAL. THERE IS NOT MUCH MORE I CAN SAY ABOUT THIS THING THAT HAPPENED. EVERYTHING HAS NOW BEEN CORRECTED, THE PLANE IS FLYING ONCE MORE, AND IT SEEMS TO ME THAT IT FLIES BETTER NOW THAN BEFORE.

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.