C177RG instructor pilot had main gear collapse after landing after aircraft electrical failure.

Attributes
ACN	507437
Time
Date	200104
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sgu.airport
State Reference	UT
Altitude	msl single value : 2900
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Cardinal 177/177RG
Operating Under FAR Part	Part 91
Flight Phase	descent : approach landing : roll
Flight Plan	None
Person 1
Affiliation	other
Function	instruction : instructor
Qualification	pilot : cfi pilot : instrument pilot : multi engine pilot : commercial
Experience	flight time last 90 days : 50 flight time total : 3800 flight time type : 400
ASRS Report	507437
Person 2
Affiliation	other
Function	instruction : trainee
Events
Anomaly	maintenance problem : improper maintenance non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	contributing factor : schedule pressure performance deficiency : fault isolation performance deficiency : testing performance deficiency : inspection performance deficiency : repair
Supplementary
Problem Areas	Company Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

Problem arose when I lost all electrical power. Electrical failure cause unknown. No circuit breakers were popped. The landing gear is electro-mechanically operated. All electrical system were off including landing gear indicator lights. When the landing gear selector was put in down position, I felt the gear come down. I was able to see the shadow of the airplane as we got close to the runway and the gear was down. The nose gear was locked down but the main gear was not locked and folded on touchdown. The aircraft sustained very minor damage. Callback conversation with reporter revealed the following information: reporter indicated that this aircraft has had a long history of electrical failures. Maintenance has not been able to find the problem. He does not know what was found this time. The instructor did not think to use the emergency gear extension system. He thought the gear locked after free fall. The reporter was giving instruction to a student when the incident occurred.

Original NASA ASRS Text

Title: C177RG INSTRUCTOR PLT HAD MAIN GEAR COLLAPSE AFTER LNDG AFTER ACFT ELECTRICAL FAILURE.

Narrative: PROB AROSE WHEN I LOST ALL ELECTRICAL PWR. ELECTRICAL FAILURE CAUSE UNKNOWN. NO CIRCUIT BREAKERS WERE POPPED. THE LNDG GEAR IS ELECTRO-MECHANICALLY OPERATED. ALL ELECTRICAL SYS WERE OFF INCLUDING LNDG GEAR INDICATOR LIGHTS. WHEN THE LNDG GEAR SELECTOR WAS PUT IN DOWN POS, I FELT THE GEAR COME DOWN. I WAS ABLE TO SEE THE SHADOW OF THE AIRPLANE AS WE GOT CLOSE TO THE RWY AND THE GEAR WAS DOWN. THE NOSE GEAR WAS LOCKED DOWN BUT THE MAIN GEAR WAS NOT LOCKED AND FOLDED ON TOUCHDOWN. THE ACFT SUSTAINED VERY MINOR DAMAGE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR INDICATED THAT THIS ACFT HAS HAD A LONG HISTORY OF ELECTRICAL FAILURES. MAINT HAS NOT BEEN ABLE TO FIND THE PROB. HE DOES NOT KNOW WHAT WAS FOUND THIS TIME. THE INSTRUCTOR DID NOT THINK TO USE THE EMER GEAR EXTENSION SYS. HE THOUGHT THE GEAR LOCKED AFTER FREE FALL. THE RPTR WAS GIVING INSTRUCTION TO A STUDENT WHEN THE INCIDENT OCCURRED.

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.