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|
Attributes | |
ACN | 287666 |
Time | |
Date | 199411 |
Day | Fri |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : zzz |
State Reference | US |
Altitude | msl bound lower : 1200 msl bound upper : 1400 |
Environment | |
Flight Conditions | VMC |
Light | Night |
Aircraft 1 | |
Controlling Facilities | tower : zzz tower : lga |
Operator | general aviation : corporate |
Make Model Name | Helicopter |
Operating Under FAR Part | Part 135 |
Flight Phase | cruise other descent : approach |
Flight Plan | VFR |
Aircraft 2 | |
Operator | general aviation : corporate |
Make Model Name | Cessna 340/340A |
Operating Under FAR Part | Part 91 |
Flight Phase | descent : approach descent other |
Flight Plan | VFR |
Person 1 | |
Affiliation | government : faa |
Function | controller : local |
Qualification | controller : radar |
Experience | controller military : 4 controller non radar : 24 controller radar : 23 controller supervisory : 2 |
ASRS Report | 287666 |
Person 2 | |
Affiliation | Other |
Function | flight crew : single pilot |
Qualification | pilot : commercial |
Events | |
Anomaly | other anomaly other |
Independent Detector | other controllera |
Resolutory Action | none taken : anomaly accepted |
Consequence | Other |
Supplementary | |
Primary Problem | Navigational Facility |
Air Traffic Incident | other |
Narrative:
I was working the local control position in the tower and I had an EMS helicopter inbound to the airport via the lake shoreline. The EMS helicopter was cga X on an established inbound route to their landing site on the west side of the airport. Cpr Y, a cessna 340, was inbound from the north on a visual approach to runway 24 via a right base leg. Cga X was at 1200 ft MSL and cpr Y was descending from 2800 ft MSL. I exchanged traffic to both aircraft. I had both aircraft in sight and was providing visual separation. The helicopter sighted the C340 at 2 NM, the C340 was at 1400 ft MSL descending. The helicopter crossed the C340's 12 O'clock position at less than 1 mi distance. The aural alarm of the ARTS iia conflict alert never sounded. When the aircraft were at a distance of more than 1 mi on diverging headings, the aural alarm sounded. The aircraft were moving away from one another before the alarm sounded. This unfortunate incident occurs on a regular basis. The conflict alert feature is supposed to aid the controller in preventing conflicts collisions: however, does not function in this manner.
Original NASA ASRS Text
Title: MISC -- DELAYED LATE CONFLICT ALERT WARNING BTWN CGA X AND CPR Y.
Narrative: I WAS WORKING THE LCL CTL POS IN THE TWR AND I HAD AN EMS HELI INBOUND TO THE ARPT VIA THE LAKE SHORELINE. THE EMS HELI WAS CGA X ON AN ESTABLISHED INBOUND RTE TO THEIR LNDG SITE ON THE W SIDE OF THE ARPT. CPR Y, A CESSNA 340, WAS INBOUND FROM THE N ON A VISUAL APCH TO RWY 24 VIA A R BASE LEG. CGA X WAS AT 1200 FT MSL AND CPR Y WAS DSNDING FROM 2800 FT MSL. I EXCHANGED TFC TO BOTH ACFT. I HAD BOTH ACFT IN SIGHT AND WAS PROVIDING VISUAL SEPARATION. THE HELI SIGHTED THE C340 AT 2 NM, THE C340 WAS AT 1400 FT MSL DSNDING. THE HELI CROSSED THE C340'S 12 O'CLOCK POS AT LESS THAN 1 MI DISTANCE. THE AURAL ALARM OF THE ARTS IIA CONFLICT ALERT NEVER SOUNDED. WHEN THE ACFT WERE AT A DISTANCE OF MORE THAN 1 MI ON DIVERGING HDGS, THE AURAL ALARM SOUNDED. THE ACFT WERE MOVING AWAY FROM ONE ANOTHER BEFORE THE ALARM SOUNDED. THIS UNFORTUNATE INCIDENT OCCURS ON A REGULAR BASIS. THE CONFLICT ALERT FEATURE IS SUPPOSED TO AID THE CTLR IN PREVENTING CONFLICTS COLLISIONS: HOWEVER, DOES NOT FUNCTION IN THIS MANNER.
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.