Pilot of small aircraft requested to file an near midair collision.

Attributes
ACN	112349
Time
Date	198905
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sbn
State Reference	IN
Altitude	msl bound lower : 6000 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : lax
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	descent other
Route In Use	enroute : on vectors enroute airway : v526
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
ASRS Report	112349
Person 2
Function	controller : approach
Qualification	controller : developmental
Events
Anomaly	conflict : airborne less severe other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

While working an small aircraft he requested the sbn approach phone # and made no indication as to why he wanted it. About 30 mins later he called sbn and informed the controller in charge he wanted to file a near miss. Controller a was training developmental a on approach radar. The small aircraft was told by the trnee to descend and maintain 5000' for traffic. At that time traffic was an small transport at his 11:30 and 8-9 mi swbnd. Shortly after, the instrument realizing that the small aircraft was descending to slow, cut in on the frequency and told small aircraft to turn right heading 350 degrees descend and maintain 4000', expedite through 5000' traffic at 11 O'clock, 6 mi, an small transport swbnd. The small aircraft was on V526 nwbnd from sbn VOR. At no time were the 2 aircraft ever closer than 3 mi. The controller working handoff saw the situation and concurs. We were working 9-12 aircraft during session. Sbn WX at that time was xbn XX52Z east 100 broken 250 overcast 15 76/67 2112/966.

Original NASA ASRS Text

Title: PLT OF SMA REQUESTED TO FILE AN NMAC.

Narrative: WHILE WORKING AN SMA HE REQUESTED THE SBN APCH PHONE # AND MADE NO INDICATION AS TO WHY HE WANTED IT. ABOUT 30 MINS LATER HE CALLED SBN AND INFORMED THE CTLR IN CHARGE HE WANTED TO FILE A NEAR MISS. CTLR A WAS TRNING DEVELOPMENTAL A ON APCH RADAR. THE SMA WAS TOLD BY THE TRNEE TO DSND AND MAINTAIN 5000' FOR TFC. AT THAT TIME TFC WAS AN SMT AT HIS 11:30 AND 8-9 MI SWBND. SHORTLY AFTER, THE INSTR REALIZING THAT THE SMA WAS DSNDING TO SLOW, CUT IN ON THE FREQ AND TOLD SMA TO TURN RIGHT HDG 350 DEGS DSND AND MAINTAIN 4000', EXPEDITE THROUGH 5000' TFC AT 11 O'CLOCK, 6 MI, AN SMT SWBND. THE SMA WAS ON V526 NWBND FROM SBN VOR. AT NO TIME WERE THE 2 ACFT EVER CLOSER THAN 3 MI. THE CTLR WORKING HDOF SAW THE SITUATION AND CONCURS. WE WERE WORKING 9-12 ACFT DURING SESSION. SBN WX AT THAT TIME WAS XBN XX52Z E 100 BROKEN 250 OVCST 15 76/67 2112/966.

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.