Date: 201205
Local time of day: 1801-2400
Location: CRQ.Tower, CA
Aircraft: Skyhawk 172/Cutlass 172
Flight plan: VFR
Flight phase: Climb
Airspace: Class D CRQ
ATC / advisory: Tower CRQ
Second aircraft: PC-12
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
Result: Air Traffic Control Issued New Clearance
Contributing factors: Airspace Structure; Human Factors; Procedure
Primary problem: Procedure

Narrative: A C172 departed Runway 24; right downwind departure; and then north. A PA28 departed Runway 24 after the C172; same direction. A light twin; VFR with SOCAL Approach; was inbound from the northwest. Local Control attempted to contact the light twin when the aircraft was approximately 5 miles northwest. No response. Assisting Local Control; I contacted SOCAL Approach on the shout line; and asked them to switch the light twin again. At this point; a PC12 was 6 miles north; being turned south directly toward the airport on a Visual Approach. The light twin was 2 miles inside CRQ Class D before we even had contact with the aircraft; and was a traffic conflict with the other three aircraft. The light twin was less than a half mile from the C172 at the same altitude before Local Control could turn them south; and was less than a half mile from the PA28 descending before Local Control could altitude restrict the aircraft for separation. At this point; a PC12 was entering our airspace from the north; on the Visual Approach; and we were still not in contact with that aircraft either due to all the traffic calls Local Control was giving. Again; SOCAL Approach was not following the Letter of Agreement (LOA); which states; TRACON Shall transfer communications to Tower no earlier than twelve (12) flying miles; but not less than seven (7) flying miles from the airport; unless otherwise coordinated. I have not been reporting every instance that SOCAL does not follow this section; because it happens EVERY DAY. At least 7 out of 10 times it results in a conflict similar to what is described above. The second incident was with another PA28. CRQ was IFR; and the weather had been sent 17 minutes earlier. We noticed the second PA28 was on a VFR tag with SOCAL; 6 miles north; inbound. Ground Control advised SOCAL we were IFR. The Controller did NOT turn the aircraft away from the airspace; just left them VFR. We did not have contact with this aircraft until they were already violating our airspace. I recommend controllers at SOCAL TRACON follow the LOA; and switch aircraft OUTSIDE of 7 flying miles from the airport; not from the runway. Either that or we delete the word 'flying' from the paragraph. There's no reason to have aircraft we're supposed to control that close to our airspace and not have communication with them. This is a consistent; chronic; blatant problem. Very few controllers here want to waste their breaks typing up reports regarding other incidents; because any time we've complained about this; it hasn't changed anything.




Synopsis: CRQ Controller described a potential conflict event involving inbound aircraft from SCT and aircraft within Class D airspace; noting SCT frequently violates the existing LOA with regard to communications transfer requirements of inbound aircraft.