Brand new flight instructor and student experience brake problem on taxi, roll into ditch.

Attributes
ACN	149208
Time
Date	199006
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : crq
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : phl
Operator	general aviation : instructional
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	ground other : taxi
Flight Plan	None
Person 1
Affiliation	Other
Function	instruction : instructor oversight : pic
Qualification	pilot : commercial pilot : cfi pilot : instrument
Experience	flight time last 90 days : 40 flight time total : 270 flight time type : 53
ASRS Report	149208
Person 2
Affiliation	Other
Function	instruction : trainee
Qualification	pilot : student
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

After completing a successful brake test roll, instrument and student proceeded to taxi to the active runway, 24. Anticipating the upcoming runup area, I instructed the student to slow down by pulling back on the power, which was completed 1/2 way down the taxiway. Noticing another aircraft approximately in the third/fourth position, I took control of the aircraft to position in the first slot. At this time, with maximum right rudder deflection, I realized a potential brake problem. Instructing student to apply brake pressure to his side produced the same result, no brakes. The ditch in front of us was unavoidable, causing the nose wheel to collapse and damage to the right wing. In my opinion, nothing more could be done to correct the problem.

Original NASA ASRS Text

Title: BRAND NEW FLT INSTRUCTOR AND STUDENT EXPERIENCE BRAKE PROBLEM ON TAXI, ROLL INTO DITCH.

Narrative: AFTER COMPLETING A SUCCESSFUL BRAKE TEST ROLL, INSTR AND STUDENT PROCEEDED TO TAXI TO THE ACTIVE RWY, 24. ANTICIPATING THE UPCOMING RUNUP AREA, I INSTRUCTED THE STUDENT TO SLOW DOWN BY PULLING BACK ON THE PWR, WHICH WAS COMPLETED 1/2 WAY DOWN THE TXWY. NOTICING ANOTHER ACFT APPROX IN THE THIRD/FOURTH POS, I TOOK CTL OF THE ACFT TO POS IN THE FIRST SLOT. AT THIS TIME, WITH MAX RIGHT RUDDER DEFLECTION, I REALIZED A POTENTIAL BRAKE PROB. INSTRUCTING STUDENT TO APPLY BRAKE PRESSURE TO HIS SIDE PRODUCED THE SAME RESULT, NO BRAKES. THE DITCH IN FRONT OF US WAS UNAVOIDABLE, CAUSING THE NOSE WHEEL TO COLLAPSE AND DAMAGE TO THE RIGHT WING. IN MY OPINION, NOTHING MORE COULD BE DONE TO CORRECT THE PROB.

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.