Narrative:

Working departure sector with departures off runway 25R and runways 19R and 19L. Our RNAV departure procedures on this configuration have runway 25 departures fly runway heading for 3 miles; then turn south to a fix called roppr; which is 7 miles southwest of the airport. Runway 19 departures do the same. Non rvav aircraft depart runway 25 heading to 3 DME; then turn to a 190 degree heading. Off runway 19; they fly runway heading to 3 DME and then turn to a 210 degree heading; all climbing to 7000 ft. As you can tell; if tower is departing runway 25 and runway 19; our procedures are designed to put two departures at the same place at the same altitude (climbing above 7000 ft cannot be accomplished until the vicinity of roppr due to arrivals descending to 8000 ft). This procedure can work if tower gives the departure controller enough room between successive departures off runway 19 and runway 25; and the aircraft are like types; and wind is not a factor. It is a marginally acceptable procedure under the best of circumstances. In this instance; tower departed 10 to 12 IFR jets; most of them off runways 19L/right; all within a 15 minute window; all maintaining visual separation from the plane ahead. The first in the string was an MD83. Right behind him was a falcon 20; less than 1.35 miles in trail. When I confirmed that the falcon still had the MD83 in sight; he said yes; but in order not to pass him; he was 'reducing to 1-7-0 KTS.' less than 2 miles behind the falcon was a B737; who I immediately told that the falcon was slowing. As I was working to separate this aircraft as best as I could before and after roppr; tower launched another 4 to 5 departures; all less than 2 miles in trail; most off runway 19R/left; but one non RNAV off runway 25. As I got busier trying to provide some sort of separation; one of the departures announced that he was IMC at 7000 ft. I told the supervisor; who told tower to stop visual separation between departures. By then I had 15 or so aircraft on frequency; most within 20 flying miles of the airport. As I tried to get caught up; I noticed the non RNAV aircraft; at 7000 ft; was on an intercept with one of the runway 25 RNAV departures; just south of roppr just as the procedure is designed to do. I had to vector this aircraft due west bound and the RNAV aircraft due south bound to avoid an oe and possible near midair collision. (I believe I did not lose IFR separation; but I am not sure. After another 15 minutes or so of work; I managed to get the sector sorted out.) several issues are at fault here: 1) our departure procedures are not designed to separate airplanes. On the contrary; they are designed to put aircraft at the same spot at the same altitude. 2) too many tower controllers have no clue of the potential for disaster they create when they 'nosewheel' numerous IFR jets off the same runway with 1.5 to 2 miles between them. Several things could have helped this situation: 1) our procedures could put aircraft on diverging courses sooner after departure (some of our departures do not separate laterally until 20 plus miles from the airport). 2) tower should not launch successive IFR departures (if our departure procedures remain unchanged) unless they have 3 miles in trail or more. 3) after the 5 to 6 runway 19 departures; I should have stopped departures completely. 4) tower should have been more aware of the WX. When I left work a few minutes after this; there was a solid layer of clouds at 7000 to 8000 ft. (I judged the heights of the clouds using surrounding mountainous terrain clearly visible to the tower. I cannot emphasize this point enough: our departure procedures will result in an oe; near midair collision; or mid air before the end of 2005. Callback conversation with reporter revealed the following information: the reporter stated that he believed L30 was simply too busy to act as a test bed for RNAV departure procedures. He indicated that facility policy requires leaving departures on the RNAV as much as possible and not to 'vector' departure aircraft unless absolutely necessary. The reporter stated that the application of visual separation either by the tower and/or flight crew's coupled with the automated flight of RNAV procedures; frequently produces conflicts requiring resolution prior to any handoff to ZLA. He encountered another incident very recently that resulted in a 1 mile separation incident; resulting in a facility quality assurance review (qar) with no action taken because of the 'test' program. The reporter stated that the facility's response to this and other incidents appears to be 'just watch' and take no action; suggesting he believes the RNAV procedures; coupled with visual separation practices are unsafe.

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Original NASA ASRS Text

Title: L30 DEP CTLR EXPRESSED CONCERNS WITH EXISTING TWR DEP SEPARATION PROCS ALLOWING VIS SEPARATION ON SUCCESSIVE DEPS FROM DIFFERENT RWYS.

Narrative: WORKING DEP SECTOR WITH DEPS OFF RWY 25R AND RWYS 19R AND 19L. OUR RNAV DEP PROCS ON THIS CONFIGURATION HAVE RWY 25 DEPS FLY RWY HDG FOR 3 MILES; THEN TURN S TO A FIX CALLED ROPPR; WHICH IS 7 MILES SW OF THE ARPT. RWY 19 DEPS DO THE SAME. NON RVAV ACFT DEPART RWY 25 HDG TO 3 DME; THEN TURN TO A 190 DEG HDG. OFF RWY 19; THEY FLY RWY HDG TO 3 DME AND THEN TURN TO A 210 DEG HDG; ALL CLBING TO 7000 FT. AS YOU CAN TELL; IF TWR IS DEPARTING RWY 25 AND RWY 19; OUR PROCS ARE DESIGNED TO PUT TWO DEPARTURES AT THE SAME PLACE AT THE SAME ALT (CLBING ABOVE 7000 FT CANNOT BE ACCOMPLISHED UNTIL THE VICINITY OF ROPPR DUE TO ARRIVALS DSNDING TO 8000 FT). THIS PROC CAN WORK IF TWR GIVES THE DEP CTLR ENOUGH ROOM BETWEEN SUCCESSIVE DEPS OFF RWY 19 AND RWY 25; AND THE ACFT ARE LIKE TYPES; AND WIND IS NOT A FACTOR. IT IS A MARGINALLY ACCEPTABLE PROC UNDER THE BEST OF CIRCUMSTANCES. IN THIS INSTANCE; TWR DEPARTED 10 TO 12 IFR JETS; MOST OF THEM OFF RWYS 19L/R; ALL WITHIN A 15 MINUTE WINDOW; ALL MAINTAINING VISUAL SEPARATION FROM THE PLANE AHEAD. THE FIRST IN THE STRING WAS AN MD83. RIGHT BEHIND HIM WAS A FALCON 20; LESS THAN 1.35 MILES IN TRAIL. WHEN I CONFIRMED THAT THE FALCON STILL HAD THE MD83 IN SIGHT; HE SAID YES; BUT IN ORDER NOT TO PASS HIM; HE WAS 'REDUCING TO 1-7-0 KTS.' LESS THAN 2 MILES BEHIND THE FALCON WAS A B737; WHO I IMMEDIATELY TOLD THAT THE FALCON WAS SLOWING. AS I WAS WORKING TO SEPARATE THIS ACFT AS BEST AS I COULD BEFORE AND AFTER ROPPR; TWR LAUNCHED ANOTHER 4 TO 5 DEPS; ALL LESS THAN 2 MILES IN TRAIL; MOST OFF RWY 19R/L; BUT ONE NON RNAV OFF RWY 25. AS I GOT BUSIER TRYING TO PROVIDE SOME SORT OF SEPARATION; ONE OF THE DEPS ANNOUNCED THAT HE WAS IMC AT 7000 FT. I TOLD THE SUPVR; WHO TOLD TWR TO STOP VISUAL SEPARATION BETWEEN DEPS. BY THEN I HAD 15 OR SO ACFT ON FREQ; MOST WITHIN 20 FLYING MILES OF THE ARPT. AS I TRIED TO GET CAUGHT UP; I NOTICED THE NON RNAV ACFT; AT 7000 FT; WAS ON AN INTERCEPT WITH ONE OF THE RWY 25 RNAV DEPS; JUST S OF ROPPR JUST AS THE PROC IS DESIGNED TO DO. I HAD TO VECTOR THIS ACFT DUE W BOUND AND THE RNAV ACFT DUE S BOUND TO AVOID AN OE AND POSSIBLE NMAC. (I BELIEVE I DID NOT LOSE IFR SEPARATION; BUT I AM NOT SURE. AFTER ANOTHER 15 MINUTES OR SO OF WORK; I MANAGED TO GET THE SECTOR SORTED OUT.) SEVERAL ISSUES ARE AT FAULT HERE: 1) OUR DEP PROCS ARE NOT DESIGNED TO SEPARATE AIRPLANES. ON THE CONTRARY; THEY ARE DESIGNED TO PUT ACFT AT THE SAME SPOT AT THE SAME ALT. 2) TOO MANY TWR CTLRS HAVE NO CLUE OF THE POTENTIAL FOR DISASTER THEY CREATE WHEN THEY 'NOSEWHEEL' NUMEROUS IFR JETS OFF THE SAME RWY WITH 1.5 TO 2 MILES BETWEEN THEM. SEVERAL THINGS COULD HAVE HELPED THIS SIT: 1) OUR PROCS COULD PUT ACFT ON DIVERGING COURSES SOONER AFTER DEP (SOME OF OUR DEPS DO NOT SEPARATE LATERALLY UNTIL 20 PLUS MILES FROM THE ARPT). 2) TWR SHOULD NOT LAUNCH SUCCESSIVE IFR DEPS (IF OUR DEP PROCS REMAIN UNCHANGED) UNLESS THEY HAVE 3 MILES IN TRAIL OR MORE. 3) AFTER THE 5 TO 6 RWY 19 DEPS; I SHOULD HAVE STOPPED DEPS COMPLETELY. 4) TWR SHOULD HAVE BEEN MORE AWARE OF THE WX. WHEN I LEFT WORK A FEW MINUTES AFTER THIS; THERE WAS A SOLID LAYER OF CLOUDS AT 7000 TO 8000 FT. (I JUDGED THE HEIGHTS OF THE CLOUDS USING SURROUNDING MOUNTAINOUS TERRAIN CLEARLY VISIBLE TO THE TWR. I CANNOT EMPHASIZE THIS POINT ENOUGH: OUR DEP PROCS WILL RESULT IN AN OE; NMAC; OR MID AIR BEFORE THE END OF 2005. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT HE BELIEVED L30 WAS SIMPLY TOO BUSY TO ACT AS A TEST BED FOR RNAV DEP PROCS. HE INDICATED THAT FAC POLICY REQUIRES LEAVING DEPS ON THE RNAV AS MUCH AS POSSIBLE AND NOT TO 'VECTOR' DEP ACFT UNLESS ABSOLUTELY NECESSARY. THE RPTR STATED THAT THE APPLICATION OF VISUAL SEPARATION EITHER BY THE TWR AND/OR FLC'S COUPLED WITH THE AUTOMATED FLT OF RNAV PROCS; FREQUENTLY PRODUCES CONFLICTS REQUIRING RESOLUTION PRIOR TO ANY HDOF TO ZLA. HE ENCOUNTERED ANOTHER INCIDENT VERY RECENTLY THAT RESULTED IN A 1 MILE SEPARATION INCIDENT; RESULTING IN A FAC QUALITY ASSURANCE REVIEW (QAR) WITH NO ACTION TAKEN BECAUSE OF THE 'TEST' PROGRAM. THE RPTR STATED THAT THE FAC'S RESPONSE TO THIS AND OTHER INCIDENTS APPEARS TO BE 'JUST WATCH' AND TAKE NO ACTION; SUGGESTING HE BELIEVES THE RNAV PROCS; COUPLED WITH VISUAL SEPARATION PRACTICES ARE UNSAFE.

Data retrieved from NASA's ASRS site as of January 2009 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.