B737-800
Flight Crew Air Transport Pilot (ATP)
Confusion; Distraction; Situational Awareness; Workload
Aircraft Equipment Problem Less Severe; Ground Event / Encounter Other / Unknown
Aircraft Automation Overrode Flight Crew; Flight Crew Overcame Equipment Problem; Flight Crew Took Evasive Action; General Maintenance Action
Aircraft; Human Factors; Procedure
During my short 250 hours on this aircraft I have experienced 5 abnormal landing events. During [the most recent] event; after normal touchdown spoiler deployment occurs. Shortly after spoiler deployment occurs; the spoilers retract; the autobrakes disengage and the throttles advance. If the throttles are above idle; the thrust reversers lock. This event has occured at both flaps 30 and 40; with and without crosswind and with sink rate between 150FPM and 400FPM (estimated). The event has been countered with manual spoiler extension; manual braking and physically holding the throttles at idle with the forarm while deploying thrust reversers. The event causes increased landing rollout and stopping distance.Recommend searching FOQA data for similar incidents to determine cause of above event and take action necessary to prevent future occurrence.
The reporter stated the cause of the five similar events he has experienced has not been determined. A Check Airman said a possible cause was a TOGA button push within two seconds of touchdown before the reverser levers are pulled. If that were the case a full autothrust TOGA go around would be initiated. Outside of two seconds; a TOGA button push is ignored and the normal landing sequence is enabled. The reporter believes the possibility exists that in some older aircraft switch wear may permit inadvertent TOGA engagement.
A B737-800 Captain reported after landing the TOGA system engaged before reverse thrust was activated. Thrust levers were physically held at idle while the speedbrake and reversers were engaged.