Date: 201207
Local time of day: 1201-1800
Location: CNO.Airport, CA
Weather elements / visibility: 4
Aircraft: Cardinal 177/177RG
Operating under: Part 91
Flight plan: VFR
Flight phase: Descent
Airspace: Class D CNO
ATC / advisory: Tower CNO
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Situational Awareness; Communication Breakdown
Second reporter function: Ground; Flight Data / Clearance Delivery; Supervisor / CIC
Anomaly: ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Diverted
Contributing factors: Human Factors; Procedure; Weather
Primary problem: Procedure

Narrative: I was on Local Control and saw SCT had a C177 tagged up coming to CNO VFR. CNO was below basic VFR minimums. I called the sector (Riverside Sector) and asked if the aircraft was VFR and advised we were below minimums. SCT acknowledged the aircraft was VFR and the Controller was aware we were below minimums. SCT Controller advised he thought the pilot was going to request SVFR. SCT switched the pilot to me once the pilot was already in CNO Class D on the downwind; mid field at pattern altitude. The pilot said he wanted to land CNO. I told the pilot we were below basic VFR minimums and asked him to advise intentions. The pilot said he wanted to land. The pilot did not ask for SVFR. I did not give a landing clearance. I told the pilot I could not give a clearance to land and asked his intentions. The pilot asked to go to RAL. I handed the aircraft back off to SCT. SCT should have never let an aircraft enter my airspace. He was not pointed out or coordinated to do so. The pilot never asked for SVFR with me or with SCT; but SCT still let the pilot fly VFR into an IMC Class D. SCT should have never allowed the pilot to attempt to enter the Class D without getting the proper IFR or SVFR request from the pilot since they knew we were IMC. Educate SCT on SVFR and what below basic VFR minimums mean.


Second narrative: The weather at my facility was below basic VFR minimums; with 4 miles visibility and ceiling 800 FT overcast. There was no traffic on any frequency at the time; and I was working Ground Control; Flight Data/Clearance Delivery; and CIC combined. The Local Controller and I saw an automated hand-off from approach (SCT - Riverside and Pomona sectors combined) that was VFR and not on an approach; and was approximately 4;500 FT MSL and 8 miles northeast of CNO Airport. The Local Control called Riverside Sector on the shout line; and asked if the Controller understood the weather was less than VFR. The Local Control indicated to me that the TRACON Controller said he did; and that the pilot told him he thought he could get in to the airport. Local Control then accepted the automated hand-off. Once I learned that the TRACON Controller knew about our weather conditions I figured he had already received a SVFR request from the pilot. Unfortunately that was not the case to my knowledge. A C177 was descending north of the field; above our airspace and managed to somehow descend through the overcast layer; entering the CNO Delta approximately 2 miles north of CNO airport; southbound at 1;900 FT MSL. The C177 did not establish contact with Local Control until 1 mile north of CNO airport at approximately 1;400 FT MSL (TPA); and requested landing. Local Control advised the pilot that the weather was below basic VFR minimums; and asked his intentions. I reminded Local Control that the 7110.65 states if visibility is less than 1 mile; and the pilot reports the runway in sight you should clear them to land; but neither of us thought it applied in this situation; since the pilot had never requested SVFR clearance into the Delta surface area to begin with. Local Control made several failed attempts at trying to get the pilot to request a SVFR clearance by stating the weather is below basic VFR minimums; and asking intentions. Eventually Local Control advised the C177 that a landing clearance could not be issued because of the weather conditions. The C177 advised he would divert to RAL airport. He was on right base leg; approaching the turn to final (easily seen from the Tower); and then turned away from the runways and northbound beginning to climb. Local Control handed the C177 back to Riverside Sector and advised the Controller over the shout line that he was going to Riverside Airport instead. In all the communications with the C177; the pilot never requested SVFR clearance. I believe this happened because the RADAR Controller was not knowledgeable about SVFR; and the Local Control possibly did not use the appropriate conflict resolution. Rather than ask if he knew the weather; Local Control should have told the Approach Controller to keep the aircraft clear of the Delta unless he requests SVFR. Also; if the Approach Controller had advised the C177 to contact CNO Tower earlier; or if the C177 did not delay contacting CNO Tower until already on downwind; Local Control could have advised the pilot to remain clear before he entered the airspace. During this entire event; the C177 was the only aircraft on frequency; and the only aircraft in our airspace. He did not conflict with any other aircraft. If this event started again; with CNO Airport reporting IMC; and approach handing off a VFR aircraft; I will make sure to make it clear to TRACON Controller that the aircraft can not enter the delta surface area unless he has requested and received a SVFR clearance to do so; and unless the pilot requests SVFR to keep the aircraft clear. Perhaps a refresher on SVFR would benefit the TRACON Controller.


Synopsis: CNO Controller described an unauthorized Class D entry event during IFR conditions permitted by SCT controllers. The reporter noted that SCT controllers are in need of SVFR refresher information.