A COMPANY DEADHEADING FLC MEMBER STARTLES THE FLC OF AN MLG ACR ACFT BY BEATING ON THE COCKPIT DOOR TO ADVISE THAT THE FLAPS ARE NOT SET FOR TKOF DURING TAXI FOR TKOF.

Narrative

TAXIING OUT FOR TKOF THE FLAPS WERE LOWERED DURING THE TAXI CHK AND THE AUTO SLAT FAIL LIGHT WAS NOTED. SINCE THIS LIGHT COMES ON ONCE IN A WHILE; THE NORMAL PROC IS TO RAISE AND LOWER THE FLAPS AGAIN. THE FLAPS WERE RAISED BUT WERE NOT EXTENDED IMMEDIATELY DUE TO CONCERN OVER CHANGED TAXI INSTRUCTIONS BY ATC. WHEN WE WERE #2 FOR TKOF THE #2 ENG WAS STARTED AND THE REMAINDER OF THE TAXI CHKLIST WAS DONE. AS WE TURNED ON TO TXWY A; I CALLED FOR THE BEFORE TKOF CHKLIST. AS WE WERE #1 AT THAT TIME; I DID MY OWN FINAL CHK OF FLAPS; SLATS; MOTORS AND HORNS. AT THE SAME TIME THE FO AND I NOTICED THE FLAPS WERE NOT DOWN AND WE BOTH REACHED FOR THE HANDLE AND PUT THEM DOWN. AS THE FLAPS WERE COMING DOWN WE HEARD A LOUD KNOCK ON THE DOOR AND SOMEONE YELL 'FLAPS.' IT TURNED OUT A DEADHEADING PLT THOUGHT THAT WE WERE GOING TO FORGET TO LOWER THE FLAPS AND WAS THE ONE WHO BEAT ON THE DOOR. AFTER TALKING TO THE FSM AND ALL ELSE BEING NORMAL; WE CONTINUED THE TKOF AND A NORMAL FLT TO DCA. THE FLAPS WERE PUT DOWN LATER THAN NORMAL; THEREFORE; I CAN UNDERSTAND WHY A PLT WOULD GET A LITTLE EXCITED. THE INTENT WAS UNDERSTANDABLE BUT THE WAY HE LET US KNOW IS DEBATEABLE. ALL SYS WERE OPERATING AND AT NO TIME WERE WE IN DANGER OF ATTEMPTING A TKOF WITH NO FLAPS.