Narrative:

I was training a new radar controller on a complex position. We work the final approach course for 4 airports. Sometimes you'll get approachs to all 4 simultaneously. We had been training on somewhat busy traffic for about an hour and a half. We were just getting ready to get relieved from the position when numerous inbnds began to flood the sector. We had 8 aircraft either on final or being vectored to final at lindbergh, 3 aircraft to montgomery, one aircraft to brown and one to gillespie. The trnee was tired and I knew it and should have removed him from position but this was a good training situation and thought he should be exposed. Small aircraft X was over mission bay VORTAC heading 090 degrees for lindbergh at 5000'. Small transport Y was sebnd for mission bay or a vector for lindbergh at 7000'. Small transport Y was not receiving his calls very well and required repeats. Small transport Y was cleared to 6000' and vectored 090 degree. The plan was to run him by the small aircraft X and take him over the top and in front. The small transport Y pilot replied, ' was that for small transport Y', not really having received the transmission. The trnee, instead of repeating the clearance to 6000, an unusual altitude to use there, just said 'small transport Y affirmative.' small transport Y read back, roger, descending to 5, not all that clear even on the tape. The trnee and I missed the readback. Later I saw small transport Y descending through 200' and told the trnee to stop his descent at 6000'. The trnee argued and said he already did that. Then small transport Y was out of 5800' so I told the trnee again climb him to 6000'. Instead the trnee gave another clearance to another aircraft. Meanwhile, small transport Y is still descending. He finally climbed and turned small transport Y. There was never any danger of collision because they were separated laterally by 1.5 mi and paralleling each other.

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Original NASA ASRS Text

Title: ACR SMT READBACK WRONG ALT FOR DESCENT, CTLR IN TRAINING MISSED READBACK AND HAD LESS THAN STANDARD SEPARATION BETWEEN SMA AND SMT.

Narrative: I WAS TRNING A NEW RADAR CTLR ON A COMPLEX POS. WE WORK THE FINAL APCH COURSE FOR 4 ARPTS. SOMETIMES YOU'LL GET APCHS TO ALL 4 SIMULTANEOUSLY. WE HAD BEEN TRNING ON SOMEWHAT BUSY TFC FOR ABOUT AN HR AND A HALF. WE WERE JUST GETTING READY TO GET RELIEVED FROM THE POS WHEN NUMEROUS INBNDS BEGAN TO FLOOD THE SECTOR. WE HAD 8 ACFT EITHER ON FINAL OR BEING VECTORED TO FINAL AT LINDBERGH, 3 ACFT TO MONTGOMERY, ONE ACFT TO BROWN AND ONE TO GILLESPIE. THE TRNEE WAS TIRED AND I KNEW IT AND SHOULD HAVE REMOVED HIM FROM POS BUT THIS WAS A GOOD TRNING SITUATION AND THOUGHT HE SHOULD BE EXPOSED. SMA X WAS OVER MISSION BAY VORTAC HDG 090 DEGS FOR LINDBERGH AT 5000'. SMT Y WAS SEBND FOR MISSION BAY OR A VECTOR FOR LINDBERGH AT 7000'. SMT Y WAS NOT RECEIVING HIS CALLS VERY WELL AND REQUIRED REPEATS. SMT Y WAS CLRED TO 6000' AND VECTORED 090 DEG. THE PLAN WAS TO RUN HIM BY THE SMA X AND TAKE HIM OVER THE TOP AND IN FRONT. THE SMT Y PLT REPLIED, ' WAS THAT FOR SMT Y', NOT REALLY HAVING RECEIVED THE XMISSION. THE TRNEE, INSTEAD OF REPEATING THE CLRNC TO 6000, AN UNUSUAL ALT TO USE THERE, JUST SAID 'SMT Y AFFIRMATIVE.' SMT Y READ BACK, ROGER, DSNDING TO 5, NOT ALL THAT CLR EVEN ON THE TAPE. THE TRNEE AND I MISSED THE READBACK. LATER I SAW SMT Y DSNDING THROUGH 200' AND TOLD THE TRNEE TO STOP HIS DSNT AT 6000'. THE TRNEE ARGUED AND SAID HE ALREADY DID THAT. THEN SMT Y WAS OUT OF 5800' SO I TOLD THE TRNEE AGAIN CLB HIM TO 6000'. INSTEAD THE TRNEE GAVE ANOTHER CLRNC TO ANOTHER ACFT. MEANWHILE, SMT Y IS STILL DSNDING. HE FINALLY CLBED AND TURNED SMT Y. THERE WAS NEVER ANY DANGER OF COLLISION BECAUSE THEY WERE SEPARATED LATERALLY BY 1.5 MI AND PARALLELING EACH OTHER.

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.