MD80 flight crew experiences captain's airspeed indicator failure during the takeoff roll. After the...

Narrative:

On takeoff at about 110 KIAS; the captain's airspeed indicator failed to zero with a visible flag; the flight director disappeared; and the auto throttles disconnected. I continued the takeoff and transferred control of the aircraft to the first officer after we determined his instruments were correct. Since the pitch window blanked; the flight directors went out of view; and the autopilot kicked off after selected; I went to the CADC failure checklist. After switching to CADC both on 2 my airspeed started to increase; but it went to 300 KIAS even though we were doing 250. The standby; first officer's; and the ground speed read 250 KIAS. Then the over speed warning came on and we received a TAS input failure and a mach trim inoperative light. Declared an emergency and ran the appropriate checklists. Over speed warning quit after pulling appropriate circuit breaker. [We] returned for an uneventful landing below max landing weight.

Original NASA ASRS Text

Title: MD80 flight crew experiences Captain's airspeed indicator failure during the takeoff roll. After the rotate call; control is transfered to the First Officer and the flight returns to the departure airport.

Narrative: On takeoff at about 110 KIAS; the Captain's airspeed indicator failed to zero with a visible flag; the flight director disappeared; and the auto throttles disconnected. I continued the takeoff and transferred control of the aircraft to the First Officer after we determined his instruments were correct. Since the pitch window blanked; the flight directors went out of view; and the autopilot kicked off after selected; I went to the CADC failure checklist. After switching to CADC both on 2 my airspeed started to increase; but it went to 300 KIAS even though we were doing 250. The standby; First Officer's; and the ground speed read 250 KIAS. Then the over speed warning came on and we received a TAS input failure and a mach trim inoperative light. Declared an emergency and ran the appropriate checklists. Over speed warning quit after pulling appropriate Circuit Breaker. [We] returned for an uneventful landing below max landing weight.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	932883
Time
Date	201102
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Night
Aircraft 1
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Takeoff
Flight Plan	IFR
Component
Aircraft Component	Air Data Computer
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Not Flying First Officer
Events
Anomaly	Aircraft Equipment Problem Critical

MD80 flight crew experiences captain's airspeed indicator failure during the takeoff roll. After the rotate call; control is transfered to the first officer and the flight returns to the departure airport.