Operational error creates an near midair collision.

Attributes
ACN	148269
Time
Date	199006
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dhn
State Reference	AL
Altitude	msl bound lower : 1000 msl bound upper : 3000
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dhn tower : dhn
Operator	other
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent : approach
Route In Use	approach : straight in arrival other
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent : approach
Route In Use	approach : visual arrival other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 2000
ASRS Report	148269
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac non adherence : required legal separation non adherence : far non adherence : clearance other anomaly other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other other
Consequence	Other
Miss Distance	horizontal : 0 vertical : 300
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Operational Error
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

My position: 7 mi out, 3000', 140 KTS. Cairns approach control asked me to slow the aircraft down to approach speed (120 KTS), which I did, and told him that I had the airport in sight. Cairns cleared me for the visibility approach and instructed me to contact dhn tower. After contacting dhn tower I started my descent out of 3000'. When dhn tower asked me how far I was out, I told them: 4-5 mi on final for 13. The tower advised me of an small transport Y also on final 2 mi ahead of my position. I told the tower that I was looking. After I had flown another 2 mi (descending) I still didn't see the small transport Y and started to worry. At the time I wanted to call the tower for a report on the small transport Y ahead of me. The tower called me and told me that the small transport Y was now 1 mi ahead of me. I didn't see any aircraft. Then the small transport Y told the tower that it was the small transport X (me) who was ahead of the small transport Y (apparently I passed the small transport Y overhead and the controller didn't notice it). The tower finally asked me to identify and instructed me to make a go around. Like it or not, I never saw the small transport Y (maybe my vision was obstructed by the nose and or compass in my aircraft). I also think that the controller never idented me on her scope until it was too late.

Original NASA ASRS Text

Title: OPERATIONAL ERROR CREATES AN NMAC.

Narrative: MY POS: 7 MI OUT, 3000', 140 KTS. CAIRNS APCH CTL ASKED ME TO SLOW THE ACFT DOWN TO APCH SPD (120 KTS), WHICH I DID, AND TOLD HIM THAT I HAD THE ARPT IN SIGHT. CAIRNS CLRED ME FOR THE VIS APCH AND INSTRUCTED ME TO CONTACT DHN TWR. AFTER CONTACTING DHN TWR I STARTED MY DSNT OUT OF 3000'. WHEN DHN TWR ASKED ME HOW FAR I WAS OUT, I TOLD THEM: 4-5 MI ON FINAL FOR 13. THE TWR ADVISED ME OF AN SMT Y ALSO ON FINAL 2 MI AHEAD OF MY POS. I TOLD THE TWR THAT I WAS LOOKING. AFTER I HAD FLOWN ANOTHER 2 MI (DSNDING) I STILL DIDN'T SEE THE SMT Y AND STARTED TO WORRY. AT THE TIME I WANTED TO CALL THE TWR FOR A RPT ON THE SMT Y AHEAD OF ME. THE TWR CALLED ME AND TOLD ME THAT THE SMT Y WAS NOW 1 MI AHEAD OF ME. I DIDN'T SEE ANY ACFT. THEN THE SMT Y TOLD THE TWR THAT IT WAS THE SMT X (ME) WHO WAS AHEAD OF THE SMT Y (APPARENTLY I PASSED THE SMT Y OVERHEAD AND THE CTLR DIDN'T NOTICE IT). THE TWR FINALLY ASKED ME TO IDENT AND INSTRUCTED ME TO MAKE A GAR. LIKE IT OR NOT, I NEVER SAW THE SMT Y (MAYBE MY VISION WAS OBSTRUCTED BY THE NOSE AND OR COMPASS IN MY ACFT). I ALSO THINK THAT THE CTLR NEVER IDENTED ME ON HER SCOPE UNTIL IT WAS TOO LATE.

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.