Flight crew of B752 experience stall warning alert on approach to sdf, ca.

Attributes
ACN	617421
Time
Date	200404
Day	Sun
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : sdf.airport
State Reference	KY
Altitude	msl single value : 2500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : sdf.tracon
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : sdf.tracon
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Route In Use	approach : visual
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 80 flight time total : 10000 flight time type : 700
ASRS Report	617421
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne less severe non adherence : company policies non adherence : published procedure other anomaly other anomaly
Independent Detector	aircraft equipment other aircraft equipment : stick shaker (stall warning) other flight crewa other flight crewb
Resolutory Action	flight crew : diverted to alternate
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

Arriving sdf, 3 NM (on TCASII) behind another aircraft. Captain says to tell approach we have traffic ahead in sight and will accept a visual approach and follow traffic ahead. Captain assesses his distance behind preceding airplane and decides he is following too close, so he decides to start slowing down to get more spacing and also decides to square his turn from base leg to final to increase spacing. Captain sees that he is going to overshoot the runway centerline in his effort to square his turn from base to final, calls for some flaps, (5 degrees), but before the flaps can track down, he banks approximately 25 degrees to the right to correct the overshooting final turn and the 'stick shaker stall warning' activates. I note airspeed at 180 KIAS, bank 25 degrees, spoilers extended and flaps at 1 degree, slowly going to flaps 5 degrees. Aircraft gross weight probably at 180000 pounds is just a guess. Captain lowers spoilers and stall activation/warning ceases, flaps make it to 5 degree setting. Pilot and copilot had fixated on traffic ahead, aided by TCASII and subsequently distraction by overshooting turn to final. Crew/captain late in configuring with flaps and speed for developing situation. We will never know, but this may have been a 'save' on the part of the stick shaker stall warning system. Warning system at least warned crew of developing bad situation (accelerated stall). Shaker would/did likely terminate upon captain stowing spoilers/and flaps tracking to commanded position, and coming out of bank.

Original NASA ASRS Text

Title: FLT CREW OF B752 EXPERIENCE STALL WARNING ALERT ON APCH TO SDF, CA.

Narrative: ARRIVING SDF, 3 NM (ON TCASII) BEHIND ANOTHER ACFT. CAPT SAYS TO TELL APCH WE HAVE TFC AHEAD IN SIGHT AND WILL ACCEPT A VISUAL APCH AND FOLLOW TFC AHEAD. CAPT ASSESSES HIS DISTANCE BEHIND PRECEDING AIRPLANE AND DECIDES HE IS FOLLOWING TOO CLOSE, SO HE DECIDES TO START SLOWING DOWN TO GET MORE SPACING AND ALSO DECIDES TO SQUARE HIS TURN FROM BASE LEG TO FINAL TO INCREASE SPACING. CAPT SEES THAT HE IS GOING TO OVERSHOOT THE RWY CTRLINE IN HIS EFFORT TO SQUARE HIS TURN FROM BASE TO FINAL, CALLS FOR SOME FLAPS, (5 DEGS), BUT BEFORE THE FLAPS CAN TRACK DOWN, HE BANKS APPROX 25 DEGS TO THE R TO CORRECT THE OVERSHOOTING FINAL TURN AND THE 'STICK SHAKER STALL WARNING' ACTIVATES. I NOTE AIRSPD AT 180 KIAS, BANK 25 DEGS, SPOILERS EXTENDED AND FLAPS AT 1 DEG, SLOWLY GOING TO FLAPS 5 DEGS. ACFT GROSS WT PROBABLY AT 180000 LBS IS JUST A GUESS. CAPT LOWERS SPOILERS AND STALL ACTIVATION/WARNING CEASES, FLAPS MAKE IT TO 5 DEG SETTING. PLT AND COPLT HAD FIXATED ON TFC AHEAD, AIDED BY TCASII AND SUBSEQUENTLY DISTR BY OVERSHOOTING TURN TO FINAL. CREW/CAPT LATE IN CONFIGURING WITH FLAPS AND SPD FOR DEVELOPING SIT. WE WILL NEVER KNOW, BUT THIS MAY HAVE BEEN A 'SAVE' ON THE PART OF THE STICK SHAKER STALL WARNING SYS. WARNING SYS AT LEAST WARNED CREW OF DEVELOPING BAD SIT (ACCELERATED STALL). SHAKER WOULD/DID LIKELY TERMINATE UPON CAPT STOWING SPOILERS/AND FLAPS TRACKING TO COMMANDED POS, AND COMING OUT OF BANK.

Data retrieved from NASA's ASRS site as of July 2007 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.