Crp controller described a minimal separation event when using lateral separation between an arrival...

Narrative:

I was working approach. I had just assumed the position. The previous controller had released aircraft X from hrl on a heading of 090; climbing to 8;000. There was an area of moderate weather approximately 15 miles in diameter about 17 miles northeast of hrl. I had cleared aircraft Y for an ILS approach when he was about 18 or 20 miles north of hrl. He had captured the localizer and was flying inbound. I switched him to the tower. Meanwhile; aircraft X departed. I let him fly east for a bit then turned him northeast. The plan was to not force him to fly 18 or 20 miles east to get around the weather. If he turned north; he could stay west of it. I gave him a heading which would take him west of the weather; and in my judgment; keep him at least three miles east of aircraft Y; as he tracked inbound on the localizer. The supervisor looked at the radar and told me he thought I should turn aircraft X. I gave aircraft X a ten degree turn to the right. I asked the supervisor what he was concerned about and he did not think I would have the required three miles as the two aircraft passed. I certainly would not have altitude; as aircraft X was climbing extremely slowly. I used the stars equipment to measure the distance between the two and had over 4 miles. The distance did seem to be narrowing a bit; but I never thought the two would get to be less than three miles. I watched; using the measuring equipment in stars and never saw anything less than 3.4 miles between the two aircraft. The supervisor later went and checked the tapes and recorded data information and told me that; in his judgment; the two planes did; in fact; get closer than 3 miles. I never observed any such loss of separation; but evidently I was mistaken; as the supervisor informed me of such. It is my opinion that I never lost three miles; however; when the supervisor told me I was wrong; he suggested I file this report. In the future; however; I will absolutely ensure that no two airplanes ever get this close together. Recommendation; my only recommendation to prevent a re-occurrence of this event is for me to strive harder to ensure that I never let any two airplanes get anywhere near three miles from each other.

Original NASA ASRS Text

Title: CRP Controller described a minimal separation event when using lateral separation between an arrival and departure aircraft. Observing Supervisor questioned the developing event and suggested the issuance of turns. The Controller discounted the recommendation.

Narrative: I was working approach. I had just assumed the position. The previous Controller had released Aircraft X from HRL on a heading of 090; climbing to 8;000. There was an area of moderate weather approximately 15 miles in diameter about 17 miles northeast of HRL. I had cleared Aircraft Y for an ILS approach when he was about 18 or 20 miles north of HRL. He had captured the localizer and was flying inbound. I switched him to the Tower. Meanwhile; Aircraft X departed. I let him fly east for a bit then turned him northeast. The plan was to not force him to fly 18 or 20 miles east to get around the weather. If he turned north; he could stay west of it. I gave him a heading which would take him west of the weather; and in my judgment; keep him at least three miles east of Aircraft Y; as he tracked inbound on the localizer. The Supervisor looked at the RADAR and told me he thought I should turn Aircraft X. I gave Aircraft X a ten degree turn to the right. I asked the Supervisor what he was concerned about and he did not think I would have the required three miles as the two aircraft passed. I certainly would not have altitude; as Aircraft X was climbing extremely slowly. I used the STARS equipment to measure the distance between the two and had over 4 miles. The distance did seem to be narrowing a bit; but I never thought the two would get to be less than three miles. I watched; using the measuring equipment in STARS and never saw anything less than 3.4 miles between the two aircraft. The Supervisor later went and checked the tapes and recorded data information and told me that; in his judgment; the two planes did; in fact; get closer than 3 miles. I never observed any such loss of separation; but evidently I was mistaken; as the Supervisor informed me of such. It is my opinion that I never lost three miles; however; when the Supervisor told me I was wrong; he suggested I file this report. In the future; however; I will absolutely ensure that no two airplanes ever get this close together. Recommendation; my only recommendation to prevent a re-occurrence of this event is for me to strive harder to ensure that I never let any two airplanes get anywhere near three miles from each other.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	883546
Time
Date	201004
Local Time Of Day	0001-0600
Place
Locale Reference	HRL.Airport
State Reference	TX
Aircraft 1
Make Model Name	Small Aircraft
Flight Phase	Initial Climb
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport
Flight Phase	Final Approach
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Person 2
Function	Supervisor / CIC
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy

Crp controller described a minimal separation event when using lateral separation between an arrival and departure aircraft. Observing supervisor questioned the developing event and suggested the issuance of turns. The controller discounted the recommendation.