Nose wheel collapse on landing due to inability to extend because of failed downlock.

Attributes
ACN	101392
Time
Date	198812
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dca airport : bwi
State Reference	MD
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Light Transport
Flight Phase	descent : approach landing other
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 280 flight time total : 4800 flight time type : 2500
ASRS Report	101392
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : unable other
Consequence	other
Supplementary
Primary Problem	Aircraft

Narrative:

On approach to landing at dca, our nose gear failed to lock down. Aircraft light transport. Our indications were two green main gear lights, one red nose gear light. We cycled the gear up and down twice with no corrective action. We abandoned the approach and completed the procedure for this problem according to the airplane flight manual. This didn't correct the problem so we completed two low flybys for visual inspection. Tower informed us gear was down but appeared 'cocked at an angle'. Dca tower wanted us to divert to iad dulles for landing. We elected to choose bwi baltimore instead. Decision was influenced by runway length. Emergency crews and our company had full maintenance available. We approached and landed on runway 33L at bwi. Landing was accomplished at vref with a T/D as light as possible. On rollout full up elevator and elevator trim were used to lighten load on the nose gear. No braking or reverse thrust were used and at a speed of approximately 25 KTS the nose gear gently folded up and the aircraft ground to a halt. Aircraft damage was minimal. Maintenance review showed a failed down lock.

Original NASA ASRS Text

Title: NOSE WHEEL COLLAPSE ON LNDG DUE TO INABILITY TO EXTEND BECAUSE OF FAILED DOWNLOCK.

Narrative: ON APCH TO LNDG AT DCA, OUR NOSE GEAR FAILED TO LOCK DOWN. ACFT LTT. OUR INDICATIONS WERE TWO GREEN MAIN GEAR LIGHTS, ONE RED NOSE GEAR LIGHT. WE CYCLED THE GEAR UP AND DOWN TWICE WITH NO CORRECTIVE ACTION. WE ABANDONED THE APCH AND COMPLETED THE PROC FOR THIS PROB ACCORDING TO THE AIRPLANE FLT MANUAL. THIS DIDN'T CORRECT THE PROB SO WE COMPLETED TWO LOW FLYBYS FOR VISUAL INSPECTION. TWR INFORMED US GEAR WAS DOWN BUT APPEARED 'COCKED AT AN ANGLE'. DCA TWR WANTED US TO DIVERT TO IAD DULLES FOR LNDG. WE ELECTED TO CHOOSE BWI BALTIMORE INSTEAD. DECISION WAS INFLUENCED BY RWY LENGTH. EMER CREWS AND OUR COMPANY HAD FULL MAINT AVAILABLE. WE APCHED AND LANDED ON RWY 33L AT BWI. LNDG WAS ACCOMPLISHED AT VREF WITH A T/D AS LIGHT AS POSSIBLE. ON ROLLOUT FULL UP ELEVATOR AND ELEVATOR TRIM WERE USED TO LIGHTEN LOAD ON THE NOSE GEAR. NO BRAKING OR REVERSE THRUST WERE USED AND AT A SPD OF APPROX 25 KTS THE NOSE GEAR GENTLY FOLDED UP AND THE ACFT GND TO A HALT. ACFT DAMAGE WAS MINIMAL. MAINT REVIEW SHOWED A FAILED DOWN LOCK.

Data retrieved from NASA's ASRS site as of August 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.