Date: 201403
Local time of day: 1201-1800
Location: SMO.Airport, CA
Light: Daylight
Aircraft: Small Aircraft; High Wing; 1 Eng; Retractable Gear
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Initial Climb
Airspace: Class D SMO
ATC / advisory: Tower SMO
Reporter organization: Government
Reporter function: Local
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown
Second reporter function: Single Pilot; Pilot Flying
Anomaly: ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural FAR
Detector: Person Air Traffic Control
When detected: In-flight
Contributing factors: Procedure
Primary problem: Procedure

Narrative: Aircraft X called to depart VFR flight following to UDD. He made a right turn at shoreline; as is issued in his instructions. Before I switched him to SCT; I told him to make sure he cleared all the way out of Class D to west and to remain clear of Class D before turning east. He asked if I wanted him clear of D[elta]. I explained we sometimes have a problem with aircraft departing to east. They contact SCT and then turn around and fly right back through our airspace. I told him to make sure when he was west to stay outside or above our airspace. He indicated he understood and I switched him. Less than a minute later I observed him turn around and start to fly back towards airport at 1;800 FT. I tried to call him but he did not respond.I had just had a discussion with another controller about this yesterday. Our instructions [are] to VFR flight following aircraft off of SMO is to turn right at the shoreline. I think it should include instructions to clear the Class D to west and then remain clear. The reason is; many pilots seem unaware that just because they are talking to Approach Control; does not let them enter another airspace. We switch them in our airspace; thinking they will continue west and they turn and fly though final at dangerous altitudes. (Because they never left D[elta] when we switch them; this is legal; but not good!) We have the same problem with pilots coming to us from the mini route over LAX or inbound leaving flight following. They think that because they have a beacon code and were talking to someone; they are okay to enter without establishing radio communications. I think this is a pilot instruction problem also.


Second narrative: Possible pilot deviation according to SMO Tower. After talking to the Controller in the Tower; the incident was described as a procedural problem. On departure; Tower issued confusing instructions. Tower said to proceed west and stay out of Delta airspace. Since I was in Delta airspace at the time; I took it to mean after leaving Delta airspace; not to reenter it. My heading was more northwest than west and I may have contacted SoCal before I was completely out of Delta airspace. When I contacted ATC (SoCal) they gave me the phone # with possible pilot deviation.I think the Tower instructions were confusing - telling me to stay out of Delta airspace when I was in it as soon as I departed. Instructions could have been given on the ground when the squawk code was given or more clearly in the air. Example: fly heading 270 degrees contact SoCal after leaving Delta airspace. Communication is an area we can always improve on. As a pilot I should have quiz[zed] her request since it was not real clear or normal terminology. I should have requested clarification.After talking to the Controller; this procedure is unique to SMO. If I had not requested a squawk code on the ground then I could have flown my normal right down wind departure to the north which I did later in the day on my return flight.Evidently SMO procedure is if you get a squawk code on the ground; you are to fly west before talking to SoCal. If you don't get the code ahead of time; you can do a normal down wind departure to the north then talk to SoCal and get a squawk.


Synopsis: SMO Tower Controller reported an aircraft experienced an Class Delta airspace violation after leaving it west bound and then entering it again without clearance eastbound.