Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 103; Flight Crew Total 3272; Flight Crew Type 1950
Deviation - Altitude Excursion From Assigned Altitude; Inflight Event / Encounter Wake Vortex Encounter; Inflight Event / Encounter Loss Of Aircraft Control
Air Traffic Control Issued Advisory / Alert; Flight Crew Regained Aircraft Control
Procedure; Environment - Non Weather Related
Holding short of runway 30L at taxiway B; my takeoff clearance was 'back taxi to taxiway Alpha for wake separation; cleared for takeoff 30L'. There was a 737 departing immediately ahead of me; apparently also on the TECKY3 SID.After climbing up and around on the TECKY3; level at 5000 feet per the procedure; autopilot engaged in altitude hold mode; speed of 200 knots (under a Class B shelf) and just as NORCAL gave me a climb instruction; the plane entered an uncommanded sudden drop of 400 feet; at a rate of 1200fpm. I disconnected the autopilot and began the climb just as NORCAL advised me that I appeared to be descending.Even with thoughtful wake separation on the initial takeoff sequencing; precisely following a larger aircraft on the same lateral and vertical routing; at the same speeds; can lead to some surprises.
C25B pilot reported encountering wake turbulence climbing out of SJC in trail of a B737.