Less than legal separation on approach to lax runway 25R-left.

Attributes
ACN	89253
Time
Date	198806
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	msl bound lower : 1000 msl bound upper : 10000
Environment
Flight Conditions	Mixed
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : lax
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	descent : approach descent other
Route In Use	arrival : profile descent
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport
Flight Phase	descent : approach descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp pilot : cfi pilot : commercial
Experience	flight time last 90 days : 120 flight time total : 10175 flight time type : 3500
ASRS Report	89253
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 750 vertical : 20
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We were cleared on a profile descent to lax runway 25L and on course. At 30 DME we were told to stay on the runway 25L ILS/localizer until establishing a visual with the airport. Then cleared to land on runway 25R. Air carrier Y jet was then cleared from the south to land on runway 25L. The conditions were very murky and no visual contact with the airport was established until we broke out of a cloud deck at 900' on the ILS to runway 25L. We sidestepped to runway 25R and landed. During the last 10 mi air carrier Y and our flight were both told to remain as cleared on the ILS 25L, we could both see the other's lights rapidly converging and expressed this to approach control and tower. I slipped 1 DOT right of the localizer to allow a buffer and still not interfere with approachs to the 24 runways. Air carrier Y again asked approach if we were on the runway 25L localizer. No answer. We were still IFR and expressing concern at converging on the same localizer and each other though cleared to land VFR on different runways. At the last minute, approach told air carrier Y to go around. We continued on the runway 25L ILS and sidestepped to runway 25R. Airport was reporting VFR. My suggestion: approach should not clear 2 aircraft to intercept the same localizer west/O sep and not be very aware of visibility or restrictive WX conditions. This is especially true if one is cleared to sidestep from a NAVAID only when the airport is in sight.

Original NASA ASRS Text

Title: LESS THAN LEGAL SEPARATION ON APCH TO LAX RWY 25R-L.

Narrative: WE WERE CLRED ON A PROFILE DSCNT TO LAX RWY 25L AND ON COURSE. AT 30 DME WE WERE TOLD TO STAY ON THE RWY 25L ILS/LOC UNTIL ESTABLISHING A VISUAL WITH THE ARPT. THEN CLRED TO LAND ON RWY 25R. ACR Y JET WAS THEN CLRED FROM THE S TO LAND ON RWY 25L. THE CONDITIONS WERE VERY MURKY AND NO VISUAL CONTACT WITH THE ARPT WAS ESTABLISHED UNTIL WE BROKE OUT OF A CLOUD DECK AT 900' ON THE ILS TO RWY 25L. WE SIDESTEPPED TO RWY 25R AND LANDED. DURING THE LAST 10 MI ACR Y AND OUR FLT WERE BOTH TOLD TO REMAIN AS CLRED ON THE ILS 25L, WE COULD BOTH SEE THE OTHER'S LIGHTS RAPIDLY CONVERGING AND EXPRESSED THIS TO APCH CTL AND TWR. I SLIPPED 1 DOT RIGHT OF THE LOC TO ALLOW A BUFFER AND STILL NOT INTERFERE WITH APCHS TO THE 24 RWYS. ACR Y AGAIN ASKED APCH IF WE WERE ON THE RWY 25L LOC. NO ANSWER. WE WERE STILL IFR AND EXPRESSING CONCERN AT CONVERGING ON THE SAME LOC AND EACH OTHER THOUGH CLRED TO LAND VFR ON DIFFERENT RWYS. AT THE LAST MINUTE, APCH TOLD ACR Y TO GO AROUND. WE CONTINUED ON THE RWY 25L ILS AND SIDESTEPPED TO RWY 25R. ARPT WAS RPTING VFR. MY SUGGESTION: APCH SHOULD NOT CLR 2 ACFT TO INTERCEPT THE SAME LOC W/O SEP AND NOT BE VERY AWARE OF VIS OR RESTRICTIVE WX CONDITIONS. THIS IS ESPECIALLY TRUE IF ONE IS CLRED TO SIDESTEP FROM A NAVAID ONLY WHEN THE ARPT IS IN SIGHT.

Data retrieved from NASA's ASRS site as of August 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.