Despite regular and specific observation of a normal landing gear extension; the pilot of a cessna 4...

Narrative:

A preflight inspection was performed on the aircraft before takeoff with nothing out of the ordinary noted. Normal flight of 35 minutes under VMC. Weather was scattered clouds at 3;500 ft MSL with over 10 SM visibility. Cruise altitude was 2;500 ft MSL. Thirty miles from the airport pilot started cooling engine by reducing manifold pressure 2 inches every 3 minutes. Manifold pressure was 21 inches and RPM was set to 1;700 RPM. Position report was given to airport traffic (unicom) 10 miles out and then again just turning final. First 10 degrees of flaps 6 miles out and gear down at 160 mph and last 20 degrees flaps (total 30) when airspeed reduced to 140 mph. Pilot could see two reds and two whites during descent on VASI. Pilot slowed to 120 mph or less for touchdown. Pilot checked and verified 3 green landing lights three times---on base; final and just before touchdown. Also; pilot checked that front nose gear was down via mirror on side of left engine. All 3 gears were down and locked. Just before touchdown point pilot reduced manifold pressure back to engine rumble (15' manifold pressure) and started flaring at about 5 ft above the runway. Touchdown point was at the 1;000 ft marker. First 5 seconds of landing rollout normal and then left wheel started vibrating at 1;500 ft marker and after 2;000 ft marker left gear collapsed. Aircraft propeller struck ground at about the 2;000 ft marker and skid about 2;000 ft. The last 50 ft or so the aircraft veered to the left and skid about 30 ft into the grassy area and then stopped. Pilot shut off all electrical and all fuel. Pilot and crew then safely departed aircraft with no injuries. Preflight inspection should include a more thorough inspection of the gear system with a flashlight. Annual should include a more thorough inspection of the gear system.

Original NASA ASRS Text

Title: Despite regular and specific observation of a normal landing gear extension; the pilot of a Cessna 421 suffered the collapse of the left main gear during landing roll out.

Narrative: A preflight inspection was performed on the aircraft before takeoff with nothing out of the ordinary noted. Normal flight of 35 minutes under VMC. Weather was scattered clouds at 3;500 FT MSL with over 10 SM visibility. Cruise altitude was 2;500 FT MSL. Thirty miles from the airport pilot started cooling engine by reducing manifold pressure 2 inches every 3 minutes. Manifold pressure was 21 inches and RPM was set to 1;700 RPM. Position report was given to airport traffic (Unicom) 10 miles out and then again just turning final. First 10 degrees of flaps 6 miles out and gear down at 160 MPH and last 20 degrees flaps (total 30) when airspeed reduced to 140 MPH. Pilot could see two reds and two whites during descent on VASI. Pilot slowed to 120 MPH or less for touchdown. Pilot checked and verified 3 green landing lights three times---on base; final and just before touchdown. Also; pilot checked that front nose gear was down via mirror on side of left engine. All 3 gears were down and locked. Just before touchdown point pilot reduced manifold pressure back to engine rumble (15' manifold pressure) and started flaring at about 5 FT above the runway. Touchdown point was at the 1;000 FT marker. First 5 seconds of landing rollout normal and then left wheel started vibrating at 1;500 FT marker and after 2;000 FT marker left gear collapsed. Aircraft propeller struck ground at about the 2;000 FT marker and skid about 2;000 FT. The last 50 FT or so the aircraft veered to the left and skid about 30 FT into the grassy area and then stopped. Pilot shut off all electrical and all fuel. Pilot and crew then safely departed aircraft with no injuries. Preflight inspection should include a more thorough inspection of the gear system with a flashlight. Annual should include a more thorough inspection of the gear system.

Data retrieved from NASA's ASRS site as of July 2013 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.

Attributes
ACN	1091537
Time
Date	201305
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Golden Eagle 421
Operating Under FAR Part	Part 91
Flight Phase	Landing
Route In Use	Direct
Flight Plan	VFR
Component
Aircraft Component	Gear Extend/Retract Mechanism
Person 1
Function	Single Pilot Pilot Flying
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Commercial
Experience	Flight Crew Last 90 Days 35 Flight Crew Total 810 Flight Crew Type 183
Events
Anomaly	Aircraft Equipment Problem Critical Ground Event / Encounter Ground Strike - Aircraft Ground Excursion Runway

Despite regular and specific observation of a normal landing gear extension; the pilot of a cessna 421 suffered the collapse of the left main gear during landing roll out.