Narrative:

On pdz 4 arrival into lax, just prior to turn from 277 degree course to 249 degree course onto runway 25L final at arnes, following B757 approximately 6 mi ahead also for runway 25L. Told by ATC 'final getting crowded, maintain heading and intercept runway 24R.' time from crossing runway 25L to intercept runway 24R about 15-20 seconds. On B757/767 it takes 4-5 mins to properly program the box, tune and identify navigation radios, brief approach and crossing fixes, runway exit plan etc. This was done to accommodate a small commuter aircraft from the south. This type of sudden runway shift in an already busy approach procedure, with accompanying sudden speed changes, causes unacceptable uncertainty, turmoil and stress in the cockpit. I have experienced this and worse in the past and have verbally complained by phone to ATC with the resulting answer 'yes, we shouldn't have done that to you,' but the practice continues. This repeated unsatisfactory handling needs to be stopped. If a non emergency aircraft can't be slotted in properly, then let him get in line like everyone else!

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Original NASA ASRS Text

Title: B767 PIC QUESTIONS RECURRENT CONDITION OF BEING ASSIGNED A NEW RWY WITHIN 20 MI OF THE ARPT AND THE PROBS OF ACFT RECONFIGN.

Narrative: ON PDZ 4 ARR INTO LAX, JUST PRIOR TO TURN FROM 277 DEG COURSE TO 249 DEG COURSE ONTO RWY 25L FINAL AT ARNES, FOLLOWING B757 APPROX 6 MI AHEAD ALSO FOR RWY 25L. TOLD BY ATC 'FINAL GETTING CROWDED, MAINTAIN HDG AND INTERCEPT RWY 24R.' TIME FROM XING RWY 25L TO INTERCEPT RWY 24R ABOUT 15-20 SECONDS. ON B757/767 IT TAKES 4-5 MINS TO PROPERLY PROGRAM THE BOX, TUNE AND IDENT NAV RADIOS, BRIEF APCH AND XING FIXES, RWY EXIT PLAN ETC. THIS WAS DONE TO ACCOMMODATE A SMALL COMMUTER ACFT FROM THE S. THIS TYPE OF SUDDEN RWY SHIFT IN AN ALREADY BUSY APCH PROC, WITH ACCOMPANYING SUDDEN SPD CHANGES, CAUSES UNACCEPTABLE UNCERTAINTY, TURMOIL AND STRESS IN THE COCKPIT. I HAVE EXPERIENCED THIS AND WORSE IN THE PAST AND HAVE VERBALLY COMPLAINED BY PHONE TO ATC WITH THE RESULTING ANSWER 'YES, WE SHOULDN'T HAVE DONE THAT TO YOU,' BUT THE PRACTICE CONTINUES. THIS REPEATED UNSATISFACTORY HANDLING NEEDS TO BE STOPPED. IF A NON EMER ACFT CAN'T BE SLOTTED IN PROPERLY, THEN LET HIM GET IN LINE LIKE EVERYONE ELSE!

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.