B737-900
Flight Crew Air Transport Pilot (ATP)
Workload; Troubleshooting; Human-Machine Interface; Training / Qualification
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution; General Maintenance Action; General Declared Emergency
Aircraft
At rotation I noticed airspeed discrepancy between Captain's and First Officer's airspeed tapes. It appeared First Officer's was correct; so as flying pilot I transferred control to First Officer. Shortly thereafter we got a Master Caution and Engine light; and I noticed both EECs were in the alternate mode. The First Officer continued flying as he had good instruments; but we had discrepancies between airspeed IVSI and altimeter indications and the IAS disagree light was on. The QRH was accomplished for EEC in the alternate mode; and we returned to the departure airport for an overweight landing. Landing was uneventful except as we configured for landing we got intermittent stick shaker indications with the Captain's airspeed tape reading approximately 45 KIAS. The cause was an Aircraft Component Malfunction.
A B737-900 EECs; Master Caution; Speed Tape; IVSI; altimeters and engine light showed malfunctioning systems so the Captain transferred control to the First Officer whose instruments were more accurate and the flight returned to land.