A afw tower controller reported an arriving aircraft on an instrument approach had a near midair col...

Narrative:

Aircraft X was on approximately 7 mile final on the ILS at 2900 feet when they were handed off to afw from approach. As soon as aircraft X was switched the conflict alert alarm went off. There was an unknown aircraft crossing from east to west 6 miles north of the field. The unknown aircraft was at 2600 feet climbing. The unknown aircraft was directly in front of aircraft X. I issued a traffic alert to aircraft X. Aircraft X reported traffic in sight and passed over the aircraft about 200 feet above it. This happens often here at afw and is happening more frequently with our increase in traffic. An adjacent non towered airport is 5 miles northeast of afw airport; outside the class D airspace. Many times aircraft depart this airport westbound and stay clear of the D airspace and never call afw tower. These aircraft routinely cross the final approach fix at 2500 feet; the same altitude as IFR aircraft on the ILS for afw. If the class D airspace was extended to the north these aircraft would have to cross further north or call afw so that we could use altitude to separate them.

Original NASA ASRS Text

Title: A AFW Tower Controller reported an arriving aircraft on an instrument approach had a NMAC with an unidentified VFR aircraft departing a satellite non towered airport.

Narrative: Aircraft X was on approximately 7 mile final on the ILS at 2900 feet when they were handed off to AFW from Approach. As soon as Aircraft X was switched the Conflict Alert alarm went off. There was an unknown aircraft crossing from east to west 6 miles north of the field. The unknown aircraft was at 2600 feet climbing. The unknown aircraft was directly in front of Aircraft X. I issued a traffic alert to Aircraft X. Aircraft X reported traffic in sight and passed over the aircraft about 200 feet above it. This happens often here at AFW and is happening more frequently with our increase in traffic. An adjacent non towered airport is 5 miles northeast of AFW airport; outside the Class D airspace. Many times aircraft depart this airport westbound and stay clear of the D airspace and never call AFW tower. These aircraft routinely cross the final approach fix at 2500 feet; the same altitude as IFR Aircraft on the ILS for AFW. If the Class D airspace was extended to the north these aircraft would have to cross further north or call AFW so that we could use altitude to separate them.

Data retrieved from NASA's ASRS site 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	1657179
Time
Date	201906
Local Time Of Day	1201-1800
Place
Locale Reference	AFW.Tower
State Reference	TX
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Small Transport Low Wing 2 Turboprop Eng
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Route In Use	Other Instrument Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	Climb
Route In Use	None
Flight Plan	VFR
Person 1
Function	Local
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 7.0
Events
Anomaly	ATC Issue All Types Conflict NMAC

A afw tower controller reported an arriving aircraft on an instrument approach had a near midair collision with an unidentified VFR aircraft departing a satellite non towered airport.