C421 pilot during landing has the left main gear collapse and departs the runway.

Attributes
ACN	698179
Time
Date	200605
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Golden Eagle 421
Operating Under FAR Part	Part 91
Flight Phase	landing : roll
Flight Plan	None
Person 1
Affiliation	company : corporate
Function	flight crew : single pilot
Qualification	pilot : multi engine pilot : commercial
Experience	flight time last 90 days : 44 flight time total : 1700 flight time type : 40
ASRS Report	698179
Events
Anomaly	aircraft equipment problem : less severe excursion : runway other anomaly
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

Night VMC with an 8-10 KT crosswind left to right from the southwest; I lined up on a long final approach to runway 32 from the south with roughly a 5 degree crab angle to the left. Landing gear down and locked; final check complete; I crossed the fence and transitioned to left wing low for the crosswind. All indications normal I reduced throttles; gently flared; and touched the left main gear wheel first whereby an instant squeal of the tire sounded followed by an abrupt yaw to the left. I instinctively applied right rudder; at which time all landing gear wheels were on the runway; in an effort to keep the airplane properly aligned on the runway. For a brief moment; the pull to the left subsided then immediately returned; uncontrollable; and forced the airplane off the left side of the runway. Off the runway in the grass the airplane spun approximately 120 degrees from runway heading and slid to a stop with the left wing lower than the right. I immediately commanded 'get out! Get out! Get out!' whereby all 3 occupants in addition to myself exited the airplane through the main door. Upon verifying all occupants safely out of the airplane; I scrambled back in to close the mixture levers and throw the gang bars (battery; alternators; magnetos). I secured the airplane; and left with the others.

Original NASA ASRS Text

Title: C421 PLT DURING LNDG HAS THE L MAIN GEAR COLLAPSE AND DEPARTS THE RWY.

Narrative: NIGHT VMC WITH AN 8-10 KT XWIND L TO R FROM THE SW; I LINED UP ON A LONG FINAL APCH TO RWY 32 FROM THE S WITH ROUGHLY A 5 DEG CRAB ANGLE TO THE L. LNDG GEAR DOWN AND LOCKED; FINAL CHK COMPLETE; I CROSSED THE FENCE AND TRANSITIONED TO L WING LOW FOR THE XWIND. ALL INDICATIONS NORMAL I REDUCED THROTTLES; GENTLY FLARED; AND TOUCHED THE L MAIN GEAR WHEEL FIRST WHEREBY AN INSTANT SQUEAL OF THE TIRE SOUNDED FOLLOWED BY AN ABRUPT YAW TO THE L. I INSTINCTIVELY APPLIED R RUDDER; AT WHICH TIME ALL LNDG GEAR WHEELS WERE ON THE RWY; IN AN EFFORT TO KEEP THE AIRPLANE PROPERLY ALIGNED ON THE RWY. FOR A BRIEF MOMENT; THE PULL TO THE L SUBSIDED THEN IMMEDIATELY RETURNED; UNCTLABLE; AND FORCED THE AIRPLANE OFF THE L SIDE OF THE RWY. OFF THE RWY IN THE GRASS THE AIRPLANE SPUN APPROX 120 DEGS FROM RWY HDG AND SLID TO A STOP WITH THE L WING LOWER THAN THE R. I IMMEDIATELY COMMANDED 'GET OUT! GET OUT! GET OUT!' WHEREBY ALL 3 OCCUPANTS IN ADDITION TO MYSELF EXITED THE AIRPLANE THROUGH THE MAIN DOOR. UPON VERIFYING ALL OCCUPANTS SAFELY OUT OF THE AIRPLANE; I SCRAMBLED BACK IN TO CLOSE THE MIXTURE LEVERS AND THROW THE GANG BARS (BATTERY; ALTERNATORS; MAGNETOS). I SECURED THE AIRPLANE; AND LEFT WITH THE OTHERS.

Data retrieved from NASA's ASRS site as of January 2009 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.