Narrative:

Arriving to lax from north, on 070 degree heading, east of santa monica VOR. Airport ATIS calling for ILS runway 24R and runway 25L in use, 2 mi visibility with haze. On downwind, approach control called out an air carrier small transport Y at our 3 O'clock position, and on final to lax. We called the aircraft in sight. We were turned on a base heading, with the small transport ahead of us. We were setting up for the ILS runway 24R. On our final intercept heading, and clearance for approach, I was confused as to exactly where the small transport was going. He was in front of us, and lined up with the north complex. After inquiring, lax approach advised that the small transport was going to runway 24L, and we were cleared to runway 24R, both on ILS approachs. The ILS runway 24L approach is a new approach. At about 1 1/2 mi saw the runway, and saw that the small transport in fact had shot the runway 24L approach. We landed on runway 24R. In summary: in all the approachs that I have done at lax, during IFR conditions, the outboard runways 24R and 25L are usually used. This procedure seemed rare, the fact that 2 aircraft were going to north complex ILS approachs. We, as crew members, are relying on controllers' knowledge of ATC procedures. I did not like that later ground said they were trying this procedure out, but the small transport I believe complained about the procedure, as we did also. A smaller aircraft behind a heavy, both on ILS approachs to the runway 24L and right runways at minimal spacing during IFR conditions, is not a good procedure! When flying an ILS approach, it is not time to be looking visually for other aircraft for the purpose of determining which runway that aircraft is going to, especially when approach control allows this. I question the legality of the procedure allowed by lax approach control. Callback conversation with facility specialist revealed the following information: analyst called facility to discuss use of visual separation. Specialist stated that they do not have anything formal set up on this. An ILS was added to runway 24L recently and occasionally will use dual parallel approachs to both runways 24R and 24L. This procedure is seldom used by the controller, but according to the specialist, is legal. The aircraft has to have the other aircraft in sight, then will clear him for an ILS approach and to maintain visual separation from the other aircraft. The controller handbook doesn't stipulate that visual approachs can only be issued in VFR conditions. As a result, it is the pilot's responsibility to conduct the ILS approach while still maintaining visual separation with the other aircraft. He emphasized that visual separation doesn't require VFR WX when issued.

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Original NASA ASRS Text

Title: PLT QUESTIONS THE USE OF CLRING AN ACFT FOR AN ILS APCH WITH THE STIPULATION TO ALSO MAINTAIN VISUAL SEPARATION WITH ANOTHER ACFT WHEN THE WX IS BELOW VFR MINIMUMS.

Narrative: ARRIVING TO LAX FROM N, ON 070 DEG HDG, E OF SANTA MONICA VOR. ARPT ATIS CALLING FOR ILS RWY 24R AND RWY 25L IN USE, 2 MI VISIBILITY WITH HAZE. ON DOWNWIND, APCH CTL CALLED OUT AN ACR SMT Y AT OUR 3 O'CLOCK POS, AND ON FINAL TO LAX. WE CALLED THE ACFT IN SIGHT. WE WERE TURNED ON A BASE HDG, WITH THE SMT AHEAD OF US. WE WERE SETTING UP FOR THE ILS RWY 24R. ON OUR FINAL INTERCEPT HDG, AND CLRNC FOR APCH, I WAS CONFUSED AS TO EXACTLY WHERE THE SMT WAS GOING. HE WAS IN FRONT OF US, AND LINED UP WITH THE N COMPLEX. AFTER INQUIRING, LAX APCH ADVISED THAT THE SMT WAS GOING TO RWY 24L, AND WE WERE CLRED TO RWY 24R, BOTH ON ILS APCHS. THE ILS RWY 24L APCH IS A NEW APCH. AT ABOUT 1 1/2 MI SAW THE RWY, AND SAW THAT THE SMT IN FACT HAD SHOT THE RWY 24L APCH. WE LANDED ON RWY 24R. IN SUMMARY: IN ALL THE APCHS THAT I HAVE DONE AT LAX, DURING IFR CONDITIONS, THE OUTBOARD RWYS 24R AND 25L ARE USUALLY USED. THIS PROC SEEMED RARE, THE FACT THAT 2 ACFT WERE GOING TO N COMPLEX ILS APCHS. WE, AS CREW MEMBERS, ARE RELYING ON CTLRS' KNOWLEDGE OF ATC PROCS. I DID NOT LIKE THAT LATER GND SAID THEY WERE TRYING THIS PROC OUT, BUT THE SMT I BELIEVE COMPLAINED ABOUT THE PROC, AS WE DID ALSO. A SMALLER ACFT BEHIND A HVY, BOTH ON ILS APCHS TO THE RWY 24L AND R RWYS AT MINIMAL SPACING DURING IFR CONDITIONS, IS NOT A GOOD PROC! WHEN FLYING AN ILS APCH, IT IS NOT TIME TO BE LOOKING VISUALLY FOR OTHER ACFT FOR THE PURPOSE OF DETERMINING WHICH RWY THAT ACFT IS GOING TO, ESPECIALLY WHEN APCH CTL ALLOWS THIS. I QUESTION THE LEGALITY OF THE PROC ALLOWED BY LAX APCH CTL. CALLBACK CONVERSATION WITH FACILITY SPECIALIST REVEALED THE FOLLOWING INFO: ANALYST CALLED FACILITY TO DISCUSS USE OF VISUAL SEPARATION. SPECIALIST STATED THAT THEY DO NOT HAVE ANYTHING FORMAL SET UP ON THIS. AN ILS WAS ADDED TO RWY 24L RECENTLY AND OCCASIONALLY WILL USE DUAL PARALLEL APCHS TO BOTH RWYS 24R AND 24L. THIS PROC IS SELDOM USED BY THE CTLR, BUT ACCORDING TO THE SPECIALIST, IS LEGAL. THE ACFT HAS TO HAVE THE OTHER ACFT IN SIGHT, THEN WILL CLR HIM FOR AN ILS APCH AND TO MAINTAIN VISUAL SEPARATION FROM THE OTHER ACFT. THE CTLR HANDBOOK DOESN'T STIPULATE THAT VISUAL APCHS CAN ONLY BE ISSUED IN VFR CONDITIONS. AS A RESULT, IT IS THE PLT'S RESPONSIBILITY TO CONDUCT THE ILS APCH WHILE STILL MAINTAINING VISUAL SEPARATION WITH THE OTHER ACFT. HE EMPHASIZED THAT VISUAL SEPARATION DOESN'T REQUIRE VFR WX WHEN ISSUED.

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.