B737-800
Flight Crew Air Transport Pilot (ATP)
Workload; Time Pressure; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; Flight Crew FLC Overrode Automation; General Declared Emergency; General Maintenance Action
Aircraft; Procedure
IAS DISAGREE and MASTER CAUTION warning near initial rotation. There was about 20 KT to 50 KT disagreements between the left and right airspeed indications I turned off automation and flew the aircraft for a downwind vector for ILS 34. [I] completed the Memory Items as pilot flying. Had the First Officer declare an emergency for overweight landing; Airspeed Disagree; and requested AARF equipment. Completed the other required checklists. Landed and had AARF command inspected the aircraft tires and brakes. [There was a] history of airspeed disagree in logbook.
[Narraitve 2 contained no additional information.]
A B737-800 IAS and MASTER CAUTION alerted near rotation speed on takeoff because of a 20 KT to 50 KT left to right airspeed indicator difference so an emergency was declared and the flight returned to the departure airport.