Narrative:

Received a request for a westbound transition through the sea class bravo airspace. Issued aircraft X a westbound transition through the airspace via the seahawks transition. The aircraft acknowledged the clearance. I then focused my attention to the aircraft I had on final. As I returned my attention back to aircraft X I witnessed that he was not complying with the clearance he had been given. Instead of flying the seahawks transiting the aircraft had immediately turned westbound after departing renton cutting through bfi airspace. As I saw aircraft Y climbing out of bfi I immediately issued traffic to aircraft X and then called bfi on the shout line to point out traffic and advise them [that aircraft X] had [aircraft Y] in sight. No brasher warning was issued as management makes the excuse that the charts can be confusing. The pilot was instructed to call the tower so that a conversation could be had with them. This is usually the most that will happen at sea for whatever reasons. Safety tends to take a back seat in my opinion. Our airspace needs to be addressed. It is too small for the amount of traffic that it now handles. Apparently management and higher union officials feels differently as they feel no need to address the issues plaguing the facility. If the matter is looked into I recommend also looking at the following day as a different controller had a similar incident with a VFR aircraft being issued the same transition and then not complying with what was expected and management just blew it off.

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Original NASA ASRS Text

Title: Seattle TRACON Controller reported a VFR aircraft did not comply with their Class B clearance and flew into conflict with an aircraft conducting an approach.

Narrative: Received a request for a westbound transition through the SEA Class Bravo airspace. Issued Aircraft X a westbound transition through the airspace via the Seahawks transition. The aircraft acknowledged the clearance. I then focused my attention to the aircraft I had on final. As I returned my attention back to Aircraft X I witnessed that he was not complying with the clearance he had been given. Instead of flying the Seahawks transiting the aircraft had immediately turned westbound after departing Renton cutting through BFI airspace. As I saw Aircraft Y climbing out of BFI I immediately issued traffic to Aircraft X and then called BFI on the shout line to point out traffic and advise them [that Aircraft X] had [Aircraft Y] in sight. No brasher warning was issued as management makes the excuse that the charts can be confusing. The pilot was instructed to call the tower so that a conversation could be had with them. This is usually the most that will happen at SEA for whatever reasons. Safety tends to take a back seat in my opinion. Our airspace needs to be addressed. It is too small for the amount of traffic that it now handles. Apparently management and higher union officials feels differently as they feel no need to address the issues plaguing the facility. If the matter is looked into I recommend also looking at the following day as a different controller had a similar incident with a VFR aircraft being issued the same transition and then not complying with what was expected and management just blew it off.

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.