Narrative:

Preflight was normal with no placards and one 'elevator feel' EICAS message signed off from the previous day. There were two cockpit jumpseat passengers and the engine start through taxi was normal. First officer was flying and the takeoff was normal until rotation when the stick shaker activated. First officer lowered the nose while maintaining a climb but the stick shaker continued. The airspeed seemed normal and was increasing. I instructed first officer to continue flying while we retracted the gear. We elected to slowly retract the flaps to clean the airplane up since the airspeed was now approaching the flap limits. We retracted the flaps to one degree and set the airspeed bug to 210 KTS while first officer hand flew the aircraft with the flight directors off using raw data. The pitch; attitude and thrust all seemed normal for a climb at 210 KTS but the stick shaker continued. My ADI had the sergeant stripes at approximately 1 degree nose low. I declared an emergency and stated we would be entering a left downwind for the runway. I handed my QRH to the jumpseat rider and asked him to see if there was a procedure for inadvertent stick shaker. There were approximately 6 EICAS messages and I could not determine which message was the initial failure and which were symptoms from the original problem. After setting first officer up for the runway; briefing the flight attendants and making a very short PA; we were on downwind with a chance to breathe a bit. The jumpseat pilot could not find a stick shaker checklist but alertly noticed my airspeed was approximately 10 to 15 KTS slower than the first officer's and standby indicator. We chose to start the 'air data computer' checklist while turning base to final. After my alternate air data switch was pressed; the stick shaker quit. We were now on final and continued to a normal landing. First officer did an outstanding job of flying the aircraft with uncertain flight indicators and jumpseater was a tremendous help. Additionally; the cabin crew responded professionally and was tremendous at directing the passengers and alleviating all passenger concerns.

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Original NASA ASRS Text

Title: A B757's stall warning began alerting during rotation for takeoff. Flaps were retracted but the stall indication continued so an emergency was declared and as the crew returned to land a jumpseater noticed a Captain's airspeed anomaly. Captain Air Data Computer ALT was selected and all systems returned to normal for the landing.

Narrative: Preflight was normal with no placards and one 'elevator feel' EICAS message signed off from the previous day. There were two cockpit jumpseat passengers and the engine start through taxi was normal. First Officer was flying and the takeoff was normal until rotation when the stick shaker activated. First Officer lowered the nose while maintaining a climb but the stick shaker continued. The airspeed seemed normal and was increasing. I instructed First Officer to continue flying while we retracted the gear. We elected to slowly retract the flaps to clean the airplane up since the airspeed was now approaching the flap limits. We retracted the flaps to one degree and set the airspeed bug to 210 KTS while First Officer hand flew the aircraft with the flight directors off using raw data. The pitch; attitude and thrust all seemed normal for a climb at 210 KTS but the stick shaker continued. My ADI had the sergeant stripes at approximately 1 degree nose low. I declared an emergency and stated we would be entering a left downwind for the runway. I handed my QRH to the jumpseat rider and asked him to see if there was a procedure for inadvertent stick shaker. There were approximately 6 EICAS messages and I could not determine which message was the initial failure and which were symptoms from the original problem. After setting First Officer up for the runway; briefing the Flight Attendants and making a very short PA; we were on downwind with a chance to breathe a bit. The jumpseat pilot could not find a stick shaker checklist but alertly noticed my airspeed was approximately 10 to 15 KTS slower than the First Officer's and standby indicator. We chose to start the 'air data computer' checklist while turning base to final. After my alternate air data switch was pressed; the stick shaker quit. We were now on final and continued to a normal landing. First Officer did an outstanding job of flying the aircraft with uncertain flight indicators and jumpseater was a tremendous help. Additionally; the cabin crew responded professionally and was tremendous at directing the passengers and alleviating all passenger concerns.

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.