Narrative:

While flying lax civet 4 ILS runway 25L procedure, I experienced an amber TCASII TA below 1000 ft with a 100 ft above target indication directly above my aircraft TCASII symbol in 5 mi range. I was previously informed of commuter traffic that was following from my rear for runway 25R. I never obtained a visual with that aircraft. Dissipating 'santa ana' wind conditions existed with gusts and a tailwind occurring on descent, sheering out to a normal west component at the surface. This event constitutes formation flight without a briefing between the leader or wingman. Responsibility regarding this procedure is not clear. The policy of metering and speed controling of aircraft into a wing-to-wing formation needs to be evaluated. For example, what would the outcome be if I were to have stopped the descent for a flap disagreement (common nuisance to this type of aircraft) while the following aircraft is in that close proximity? What if the wingman was directing his attention to a checklist at that moment? I feel that if these approachs are to be conducted, the policy needs to be defined and that the following aircraft are not to be positioned in a wingtip position. See sfo 13-2A page as an example. With 34 yrs of experience at lax, I am aware of the capacity, ATC and vortex issues. However, I feel strongly that wing-to-wing or very close proximity of commuter aircraft to heavy B757 aircraft is wrong.

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Original NASA ASRS Text

Title: A B757-200 PIC COMPLAINS OF 'FORMATION FLYING' WITH A COMMUTER FLT 100 FT ABOVE HIM WHILE ON A 3 MI FINAL TO RWY 25L AT LAX, CA.

Narrative: WHILE FLYING LAX CIVET 4 ILS RWY 25L PROC, I EXPERIENCED AN AMBER TCASII TA BELOW 1000 FT WITH A 100 FT ABOVE TARGET INDICATION DIRECTLY ABOVE MY ACFT TCASII SYMBOL IN 5 MI RANGE. I WAS PREVIOUSLY INFORMED OF COMMUTER TFC THAT WAS FOLLOWING FROM MY REAR FOR RWY 25R. I NEVER OBTAINED A VISUAL WITH THAT ACFT. DISSIPATING 'SANTA ANA' WIND CONDITIONS EXISTED WITH GUSTS AND A TAILWIND OCCURRING ON DSCNT, SHEERING OUT TO A NORMAL W COMPONENT AT THE SURFACE. THIS EVENT CONSTITUTES FORMATION FLT WITHOUT A BRIEFING BTWN THE LEADER OR WINGMAN. RESPONSIBILITY REGARDING THIS PROC IS NOT CLR. THE POLICY OF METERING AND SPD CTLING OF ACFT INTO A WING-TO-WING FORMATION NEEDS TO BE EVALUATED. FOR EXAMPLE, WHAT WOULD THE OUTCOME BE IF I WERE TO HAVE STOPPED THE DSCNT FOR A FLAP DISAGREEMENT (COMMON NUISANCE TO THIS TYPE OF ACFT) WHILE THE FOLLOWING ACFT IS IN THAT CLOSE PROX? WHAT IF THE WINGMAN WAS DIRECTING HIS ATTN TO A CHKLIST AT THAT MOMENT? I FEEL THAT IF THESE APCHS ARE TO BE CONDUCTED, THE POLICY NEEDS TO BE DEFINED AND THAT THE FOLLOWING ACFT ARE NOT TO BE POSITIONED IN A WINGTIP POS. SEE SFO 13-2A PAGE AS AN EXAMPLE. WITH 34 YRS OF EXPERIENCE AT LAX, I AM AWARE OF THE CAPACITY, ATC AND VORTEX ISSUES. HOWEVER, I FEEL STRONGLY THAT WING-TO-WING OR VERY CLOSE PROX OF COMMUTER ACFT TO HVY B757 ACFT IS WRONG.

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.