Citationjet (C525/C526) - CJ I / II / III / IV
Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Multiengine
Flight Crew Last 90 Days 100; Flight Crew Total 2800; Flight Crew Type 800
Situational Awareness
Deviation - Speed All Types; Deviation / Discrepancy - Procedural FAR; Inflight Event / Encounter CFTT / CFIT; Inflight Event / Encounter Weather / Turbulence
Flight Crew Became Reoriented; Flight Crew Took Evasive Action
Human Factors; Weather
During a FAR 91 VFR flight at night from HWD to CCR (approximately 20 nm) I encountered a Terrain Warning Alert due to avoiding/flying under Class C airspace and encountering an unexpected layer of clouds. I have flown this route multiple times in the past and am very familiar with the terrain and airspace. I visually observed the weather was clear above the HWD airport and to the North looking in the direction of flight prior to departing. I recall the automated weather was reporting approximate conditions of 800 scattered and 2;000 overcast which appeared to be a localized thin cloud layer to the south of HWD. After departure I turned to a NE heading and leveled off at 1;400 to remain outside/under OAK Class C airspace.Approximately 4 NM from the HWD airport I observed a thin scattered cloud layer that I was now flying 500-600 feet under. Normally I would have begun a climb at this point to 2;900 feet as I was clear to the NE of the Class C airspace. However; due to the scattered clouds I continued for approximately 1 minute at 1;400 feet and remained approximately 500 feet below the scattered clouds looking for a clearer area to climb through. At this point I was uncomfortable turning 180 degrees back toward HWD since I could not see the local terrain and I was aware there were hills to the west and east of my approximate position. Next the aircraft's Terrain Warning System alerted me of terrain ahead. Due to the darkness at night I still could not see the rising terrain in front of the aircraft. I initiated an immediate max power climb to 2;900 feet MSL to avoid terrain and remained outside of and under SFO class B airspace. Upon leveling off at 2;900 MSL and due to the max power setting I had selected to avoid terrain I realized the aircraft's IAS quickly increased to approximately 250 kts. I immediately reduced power and slowed to approximately 200 KTS to comply with airspeed requirements for flight under Class B airspace. There were no further Terrain Warnings and the flight was completed in VFR conditions to the intended destination without incident.Contributing factors were avoiding airspace conflicts; darkness of night; weather and the time of night which meant the HWD tower was closed. Looking back on the situation I have learned and implemented additional personal minimums; which include no VFR flight at night on that route due to the complexity of the airspace restricting the ability to climb above terrain initially UNLESS the HWD tower is open for operations and able to coordinate a Class C transition prior to departing.
C525A pilot reported receiving a GPWS terrain warning on a short night flight from HWD to CCR.