Runway incursion and confusion regarding a taxi clearance by a C172 CFI and student pilot at mri, ak...

Attributes
ACN	578122
Time
Date	200303
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mri.airport
State Reference	AK
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	ground : taxi
Flight Plan	None
Person 1
Function	instruction : instructor oversight : pic
Person 2
Affiliation	other
Function	instruction : trainee
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 30 flight time total : 95 flight time type : 95
ASRS Report	578123
Events
Anomaly	incursion : runway non adherence : far non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : became reoriented other
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Airport Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I am a CFI and was with a student for a commercial lesson. We intended to practice short field takeoffs, so while he adjusted his seat, I took the controls and taxied. We had a taxi clearance to runway 6. We usually do intersection takeoffs at intersection C from taxiway north, but we desired a full length takeoff for the short field procedure. After crossing runway 15 at intersection M, I realized intersection B does not pass through runway 6. Unless we taxied around to bravo, we would have to taxi onto runway 6 from microphone at runway 15, so we held short at microphone and asked tower for takeoff clearance on runway 6. They cleared us for takeoff on runway 6, and we departed. I called the tower controller after the flight to discuss my error, and he told me that for a full length takeoff, we should have requested a back-taxi from intersection C. Supplemental information from acn 578123: realizing the mistake, he turned around and held short of crossed runway and queried ATC.

Original NASA ASRS Text

Title: RWY INCURSION AND CONFUSION REGARDING A TAXI CLRNC BY A C172 CFI AND STUDENT PLT AT MRI, AK.

Narrative: I AM A CFI AND WAS WITH A STUDENT FOR A COMMERCIAL LESSON. WE INTENDED TO PRACTICE SHORT FIELD TKOFS, SO WHILE HE ADJUSTED HIS SEAT, I TOOK THE CTLS AND TAXIED. WE HAD A TAXI CLRNC TO RWY 6. WE USUALLY DO INTXN TKOFS AT INTXN C FROM TXWY N, BUT WE DESIRED A FULL LENGTH TKOF FOR THE SHORT FIELD PROC. AFTER XING RWY 15 AT INTXN M, I REALIZED INTXN B DOES NOT PASS THROUGH RWY 6. UNLESS WE TAXIED AROUND TO BRAVO, WE WOULD HAVE TO TAXI ONTO RWY 6 FROM MIKE AT RWY 15, SO WE HELD SHORT AT MIKE AND ASKED TWR FOR TKOF CLRNC ON RWY 6. THEY CLRED US FOR TKOF ON RWY 6, AND WE DEPARTED. I CALLED THE TWR CTLR AFTER THE FLT TO DISCUSS MY ERROR, AND HE TOLD ME THAT FOR A FULL LENGTH TKOF, WE SHOULD HAVE REQUESTED A BACK-TAXI FROM INTXN C. SUPPLEMENTAL INFO FROM ACN 578123: REALIZING THE MISTAKE, HE TURNED AROUND AND HELD SHORT OF CROSSED RWY AND QUERIED ATC.

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.