So, yesterday, I flew couple of kids on their first flight. Afternoon weather had improved over the morning, so I opted to take the kids to Watsonville, 40 miles south; I like to use coastal airports for that, and Watsonville was clear while all the other coastal airports were under low ceilings (looked like marine layer). I requested a Bay Meadows departure (see http://www.co.sanmateo.ca.us/vgn/images/portal/cit_609/119698171SQL.pdf ) off Runway 30. Flew to 1000 straight out, made my left turn, and then climbed like a bat out of hell due to terrain ahead. At 1800 feet, San Carlos tower comes on and says I'm in Class B and I should descend to 1400 immediately. I did so -- fighting on the radio is not a good idea -- but I was under the 4000 foot shelf, and would not have been inside even if I had not made my turn yet (as long as I didn't bust the surface area -- not hard to avoid due to Hwy 92). After being handed off to NorCal, I resumed my climb to 3500. I'd be happy to correct my procedures if there really was an error on my part. But I'm not seeing any error. WTF? Does San Carlos not want people near Class B? That's not easy given where the airport is. Tower clearly thought I was under (or in) the 1500 foot shelf, which only exists on the other side of the runway. Has anyone else run into this issue at San Carlos? Here's the relevant TAC, for reference. https://skyvector.com/?ll=37.504325784776,-122.22613375528887&chart=127&zoom=2 A Bay Meadows departure is a left turn about a mile prior to Hwy 92, after taking off on 30. It's named after a racetrack that no longer exists.