Parking brake not released properly, brake engages during taxi.

Attributes
ACN	298470
Time
Date	199502
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : frr
State Reference	VA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Cessna 152
Operating Under FAR Part	Part 91
Flight Phase	ground other : taxi
Flight Plan	None
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : cfi pilot : instrument pilot : commercial
Experience	flight time total : 1020
ASRS Report	298470
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	other Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

After using the parking brake while parked on the ramp, we taxied out for takeoff. On the way to the runway, the left brake engaged itself. No damage except a broken brake pad occurred. I find out later that the correct way to release the parking brake is by tapping the brakes on the pilot's side. I had tapped the brakes on my side, the copilot's side. This procedure is not in the C152 pilot operating handbook. Cessna needs to put this procedure in their manual. Callback conversation with reporter revealed the following information: reporter states his own instruction was not to use the parking brake and that is how he teaches most of his students. This particular student, however, chose to use the parking brake and reporter thought that he was releasing it by stepping on the toe brakes. His boss taught him, after the incident, the proper way to use the parking brake is to pull out the knob, step on the toe brakes and release the knob which returns to the original position. To disengage the parking brake one must touch the toe brakes on the pilot's side of the aircraft. Apparently one cannot release the parking brake from the right side. Reporter was told that the brake was close to locking which would have cartwheeled the aircraft had they been on takeoff roll. Very lucky. Analyst spoke to 3 instructors who all indicated that they teach students not to use the parking brake, but to use toe brakes only on the cessna 152. Additional inquiry using maintenance manuals indicated no procedures given for proper use of the parking brake system. Procedure indicated by our investigator is to step on the brake, pull the lever out, release the brake and then release the lever. To disengage one should step on the brake, pull out the lever and release both. Somewhere this should be spelled out to pilots.

Original NASA ASRS Text

Title: PARKING BRAKE NOT RELEASED PROPERLY, BRAKE ENGAGES DURING TAXI.

Narrative: AFTER USING THE PARKING BRAKE WHILE PARKED ON THE RAMP, WE TAXIED OUT FOR TKOF. ON THE WAY TO THE RWY, THE L BRAKE ENGAGED ITSELF. NO DAMAGE EXCEPT A BROKEN BRAKE PAD OCCURRED. I FIND OUT LATER THAT THE CORRECT WAY TO RELEASE THE PARKING BRAKE IS BY TAPPING THE BRAKES ON THE PLT'S SIDE. I HAD TAPPED THE BRAKES ON MY SIDE, THE COPLT'S SIDE. THIS PROC IS NOT IN THE C152 PLT OPERATING HANDBOOK. CESSNA NEEDS TO PUT THIS PROC IN THEIR MANUAL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES HIS OWN INSTRUCTION WAS NOT TO USE THE PARKING BRAKE AND THAT IS HOW HE TEACHES MOST OF HIS STUDENTS. THIS PARTICULAR STUDENT, HOWEVER, CHOSE TO USE THE PARKING BRAKE AND RPTR THOUGHT THAT HE WAS RELEASING IT BY STEPPING ON THE TOE BRAKES. HIS BOSS TAUGHT HIM, AFTER THE INCIDENT, THE PROPER WAY TO USE THE PARKING BRAKE IS TO PULL OUT THE KNOB, STEP ON THE TOE BRAKES AND RELEASE THE KNOB WHICH RETURNS TO THE ORIGINAL POS. TO DISENGAGE THE PARKING BRAKE ONE MUST TOUCH THE TOE BRAKES ON THE PLT'S SIDE OF THE ACFT. APPARENTLY ONE CANNOT RELEASE THE PARKING BRAKE FROM THE R SIDE. RPTR WAS TOLD THAT THE BRAKE WAS CLOSE TO LOCKING WHICH WOULD HAVE CARTWHEELED THE ACFT HAD THEY BEEN ON TKOF ROLL. VERY LUCKY. ANALYST SPOKE TO 3 INSTRUCTORS WHO ALL INDICATED THAT THEY TEACH STUDENTS NOT TO USE THE PARKING BRAKE, BUT TO USE TOE BRAKES ONLY ON THE CESSNA 152. ADDITIONAL INQUIRY USING MAINT MANUALS INDICATED NO PROCS GIVEN FOR PROPER USE OF THE PARKING BRAKE SYS. PROC INDICATED BY OUR INVESTIGATOR IS TO STEP ON THE BRAKE, PULL THE LEVER OUT, RELEASE THE BRAKE AND THEN RELEASE THE LEVER. TO DISENGAGE ONE SHOULD STEP ON THE BRAKE, PULL OUT THE LEVER AND RELEASE BOTH. SOMEWHERE THIS SHOULD BE SPELLED OUT TO PLTS.

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.