A C170 on landing roll at slow speed suddenly pitched over on its nose caused by dirt and debris in ...

Attributes
ACN	460297
Time
Date	200001
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : az05.airport
State Reference	AZ
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : det.tower
Operator	general aviation : personal
Make Model Name	Cessna 170
Operating Under FAR Part	Part 91
Flight Phase	landing : roll
Flight Plan	None
Person 1
Affiliation	government other
Qualification	pilot : atp
Experience	flight time last 90 days : 190 flight time total : 16250 flight time type : 684
ASRS Report	460297
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	other other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Shooting full stop, taxi back lndgs at my home field. Third landing was a tail low, wheel landing with 30 degrees flaps. Applied moderate braking with tailwheel still off the ground. After slowing, eased off brakes and began lowering tail. Suddenly, aircraft went over on nose. After lowering aircraft tail, discovered left brake locked tight. Had to disconnect brake line to roll aircraft off runway. Callback conversation with reporter revealed the following information: the reporter stated the aircraft was a C170 and incurred damage to the propeller and the engine required rebuilding. The reporter said he was the only one in the airplane when the incident occurred. The reporter said the aircraft was moving at a fairly slow taxi when the nose suddenly pitched over. The reporter stated the cause of the left brake locking up was dirt and debris in the master cylinder blocking return pressure when the brake was released.

Original NASA ASRS Text

Title: A C170 ON LNDG ROLL AT SLOW SPD SUDDENLY PITCHED OVER ON ITS NOSE CAUSED BY DIRT AND DEBRIS IN THE BRAKE MASTER CYLINDER.

Narrative: SHOOTING FULL STOP, TAXI BACK LNDGS AT MY HOME FIELD. THIRD LNDG WAS A TAIL LOW, WHEEL LNDG WITH 30 DEGS FLAPS. APPLIED MODERATE BRAKING WITH TAILWHEEL STILL OFF THE GND. AFTER SLOWING, EASED OFF BRAKES AND BEGAN LOWERING TAIL. SUDDENLY, ACFT WENT OVER ON NOSE. AFTER LOWERING ACFT TAIL, DISCOVERED L BRAKE LOCKED TIGHT. HAD TO DISCONNECT BRAKE LINE TO ROLL ACFT OFF RWY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT WAS A C170 AND INCURRED DAMAGE TO THE PROP AND THE ENG REQUIRED REBUILDING. THE RPTR SAID HE WAS THE ONLY ONE IN THE AIRPLANE WHEN THE INCIDENT OCCURRED. THE RPTR SAID THE ACFT WAS MOVING AT A FAIRLY SLOW TAXI WHEN THE NOSE SUDDENLY PITCHED OVER. THE RPTR STATED THE CAUSE OF THE L BRAKE LOCKING UP WAS DIRT AND DEBRIS IN THE MASTER CYLINDER BLOCKING RETURN PRESSURE WHEN THE BRAKE WAS RELEASED.

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.

A C170 on landing roll at slow speed suddenly pitched over on its nose caused by dirt and debris in the brake master cylinder.