Narrative:

I was working local control with a trnee. Small aircraft X was cleared for takeoff on runway 35 with a right turn to a heading of 020 degrees when X was about 2 mi north corp jet Y was cleared for takeoff with a right turn to 040 degrees. Both aircraft were IFR and assigned 4000'. When Y was at the north boundary the trnee instructed Y to start his right turn to 040 degrees now. He waited until Y was established on the heading before switching corp Y to departure control. He was using paragraph 5-113 of 7110.65E for sep (1 mi if courses diverge immediately after departure). The departure controller on initial contact turned Y to a heading of 360 degrees. This negated the sep we had established and caused Y to pass 1/4 mi to the left of X and at the same altitude. I think the departure controller thought both aircraft were on the salem heading and Y was going to catch X when our local procedures required X to be assigned 020 degrees on Y to be assigned 040 degrees. Callback conversation with reporter revealed the following: trnee had put corp Y into takeoff position immediately behind small aircraft X takeoff roll with intention of having Y takeoff and turn inside of X with visual sep applied. Plan did not work because corp Y was in tower frequency blind spot on runway and could not hear takeoff clearance. Pilot of Y recognized problem and moved forward on runway out of blind spot, but by that time visibility sep no longer feasible. We discussed how sep plan of trnee did not meet ATC procedure handbook criteria. Reporter agreed. There was strong wind from north. Aus TRACON has artss ii radar and so does not have C/a. Facility review found local controller did not provide required initial sep. Supplemental information from acn 98894: I was working approximately 10-12 aircraft as a combined approach/departure controller. Corp jet Y departed runway 35 climbing to 4000' on an assigned heading of 040 degrees, approximately 1 min behind small aircraft X. Small aircraft X had leveled at 4000'. Aircraft Y was approaching aircraft X at 7 O'clock position and roughly 1 mi distance when he called me, '...climbing out of 3500 for 4000'.' on initial contact I said, 'north..., radar contact, turn left heading 360 degrees.' I did not issue traffic to corp Y or to small aircraft X. IFR sep had already been lost by the time corp Y had made initial contact with me. I issued the northbound turn as an avoidance vector because the targets appeared likely to merge with both aircraft reported at the same altitude. Local controllers (a supervisor training another supervisor) did not ensure initial sep of IFR departures.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN SMA AND CORP-JET. BOTH IFR DEP FROM SAME RWY. OPERATIONAL ERROR.

Narrative: I WAS WORKING LCL CTL WITH A TRNEE. SMA X WAS CLRED FOR TKOF ON RWY 35 WITH A RIGHT TURN TO A HDG OF 020 DEGS WHEN X WAS ABOUT 2 MI N CORP JET Y WAS CLRED FOR TKOF WITH A RIGHT TURN TO 040 DEGS. BOTH ACFT WERE IFR AND ASSIGNED 4000'. WHEN Y WAS AT THE N BOUNDARY THE TRNEE INSTRUCTED Y TO START HIS RIGHT TURN TO 040 DEGS NOW. HE WAITED UNTIL Y WAS ESTABLISHED ON THE HDG BEFORE SWITCHING CORP Y TO DEP CTL. HE WAS USING PARAGRAPH 5-113 OF 7110.65E FOR SEP (1 MI IF COURSES DIVERGE IMMEDIATELY AFTER DEP). THE DEP CTLR ON INITIAL CONTACT TURNED Y TO A HDG OF 360 DEGS. THIS NEGATED THE SEP WE HAD ESTABLISHED AND CAUSED Y TO PASS 1/4 MI TO THE LEFT OF X AND AT THE SAME ALT. I THINK THE DEP CTLR THOUGHT BOTH ACFT WERE ON THE SALEM HDG AND Y WAS GOING TO CATCH X WHEN OUR LCL PROCS REQUIRED X TO BE ASSIGNED 020 DEGS ON Y TO BE ASSIGNED 040 DEGS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: TRNEE HAD PUT CORP Y INTO TKOF POS IMMEDIATELY BEHIND SMA X TKOF ROLL WITH INTENTION OF HAVING Y TKOF AND TURN INSIDE OF X WITH VISUAL SEP APPLIED. PLAN DID NOT WORK BECAUSE CORP Y WAS IN TWR FREQ BLIND SPOT ON RWY AND COULD NOT HEAR TKOF CLRNC. PLT OF Y RECOGNIZED PROB AND MOVED FORWARD ON RWY OUT OF BLIND SPOT, BUT BY THAT TIME VIS SEP NO LONGER FEASIBLE. WE DISCUSSED HOW SEP PLAN OF TRNEE DID NOT MEET ATC PROC HANDBOOK CRITERIA. RPTR AGREED. THERE WAS STRONG WIND FROM N. AUS TRACON HAS ARTSS II RADAR AND SO DOES NOT HAVE C/A. FAC REVIEW FOUND LCL CTLR DID NOT PROVIDE REQUIRED INITIAL SEP. SUPPLEMENTAL INFO FROM ACN 98894: I WAS WORKING APPROX 10-12 ACFT AS A COMBINED APCH/DEP CTLR. CORP JET Y DEPARTED RWY 35 CLBING TO 4000' ON AN ASSIGNED HDG OF 040 DEGS, APPROX 1 MIN BEHIND SMA X. SMA X HAD LEVELED AT 4000'. ACFT Y WAS APCHING ACFT X AT 7 O'CLOCK POS AND ROUGHLY 1 MI DISTANCE WHEN HE CALLED ME, '...CLBING OUT OF 3500 FOR 4000'.' ON INITIAL CONTACT I SAID, 'N..., RADAR CONTACT, TURN LEFT HDG 360 DEGS.' I DID NOT ISSUE TFC TO CORP Y OR TO SMA X. IFR SEP HAD ALREADY BEEN LOST BY THE TIME CORP Y HAD MADE INITIAL CONTACT WITH ME. I ISSUED THE NBOUND TURN AS AN AVOIDANCE VECTOR BECAUSE THE TARGETS APPEARED LIKELY TO MERGE WITH BOTH ACFT RPTED AT THE SAME ALT. LCL CTLRS (A SUPVR TRNING ANOTHER SUPVR) DID NOT ENSURE INITIAL SEP OF IFR DEPS.

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.