Captain taxies aircraft in area of non bearing asphalt.

Attributes
ACN	174641
Time
Date	199104
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : tus
State Reference	AZ
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : iah
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : atp pilot : cfi
Experience	flight time last 90 days : 20 flight time total : 6000 flight time type : 20
ASRS Report	174641
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time total : 17000 flight time type : 15500
ASRS Report	174897
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	faa : investigated
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Prepared for flight, arriving on time in operations for preflight briefing. Aircraft preparation, engine start, pushback procedures followed normal standard operation. Captain demonstrated taxi procedure to first officer. Captain suggested a demonstration of turning radius with rudder pedals and proceeded to turn around corner at the end of runway at a slow taxi pace. The aircraft then slowed to a stop quickly. The aircraft did tilt to the right. Appropriate authorities were notified. The aircraft was secured and the passenger were bussed to terminal. Upon exiting aircraft and examining right main tires, I observed that the aircraft had sunk into the taxiway pavement with the right main tires 6' outside the double yellow line. The taxi lights were still 6-8' from the main tires. The aircraft was later pulled out of the softened taxiway and no damage was found. Supplemental information from acn 174897: lcls believed recent rains had influenced integrity of fill below pavement.

Original NASA ASRS Text

Title: CAPT TAXIES ACFT IN AREA OF NON BEARING ASPHALT.

Narrative: PREPARED FOR FLT, ARRIVING ON TIME IN OPS FOR PREFLT BRIEFING. ACFT PREPARATION, ENG START, PUSHBACK PROCS FOLLOWED NORMAL STANDARD OPERATION. CAPT DEMONSTRATED TAXI PROC TO F/O. CAPT SUGGESTED A DEMONSTRATION OF TURNING RADIUS WITH RUDDER PEDALS AND PROCEEDED TO TURN AROUND CORNER AT THE END OF RWY AT A SLOW TAXI PACE. THE ACFT THEN SLOWED TO A STOP QUICKLY. THE ACFT DID TILT TO THE RIGHT. APPROPRIATE AUTHORITIES WERE NOTIFIED. THE ACFT WAS SECURED AND THE PAX WERE BUSSED TO TERMINAL. UPON EXITING ACFT AND EXAMINING RIGHT MAIN TIRES, I OBSERVED THAT THE ACFT HAD SUNK INTO THE TXWY PAVEMENT WITH THE RIGHT MAIN TIRES 6' OUTSIDE THE DOUBLE YELLOW LINE. THE TAXI LIGHTS WERE STILL 6-8' FROM THE MAIN TIRES. THE ACFT WAS LATER PULLED OUT OF THE SOFTENED TXWY AND NO DAMAGE WAS FOUND. SUPPLEMENTAL INFO FROM ACN 174897: LCLS BELIEVED RECENT RAINS HAD INFLUENCED INTEGRITY OF FILL BELOW PAVEMENT.

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.