Date: 201709
Local time of day: 0601-1200
Location: DVO.Airport, CA
Flight conditions: VMC
Weather elements / visibility: Haze / Smoke; 10
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Fixed Gear
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Cruise
Airspace: Class E NCT
ATC / advisory: TRACON NCT
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Private
Human factors: Other / Unknown
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure
Primary problem: Ambiguous

Narrative: While passing over DVO at 2;400 ft; I encountered two parachutists descending into my altitude at a distance of 1-2 miles and roughly my 2 o'clock position. I had just canceled flight following with NORCAL TRACON; and there was no mention by the controller of any active parachute activities in the area. There also was not a NOTAM of upcoming parachute drops in the area at the time of my flight briefing the night before my flight. I was flying on autopilot at the time of the incident and took control of the aircraft upon spotting the divers in order to increase our separation. DVO sits in very busy airspace just outside the SFO Mode C veil. Although a skydiving operation was established on the airport within the past several years; there is no skydiving icon on the sectional or terminal charts to indicate such activity. Additionally; although the jump activity was NOTAMed; the NOTAM was posted only 90 minutes prior to becoming active; and it is not clear that NORCAL TRACON was aware of the activity. Although there are several things I could have done better to avoid this conflict; I believe it would be worthwhile for NASA; the NTSB; and/or the FAA to review how parachute jumping activities are marked and identified. The NOTAM for this incident was from the surface to 10;000 feet. Expecting a pilot to take notice of a single line-item NOTAM for an airport along a route but not intended for landing in a 20-page briefing seems to tempt fate; and it would seem that a better means of identifying activities and their locations needs to be developed.Things I could have done differently:(1) Although I obtained a briefing the night prior to my flight; I did not get a supplemental briefing the morning of. Assuming the NOTAM had been posted by the time I got my briefing; I might have seen it though I worry it likely would have been lost in the lengthy briefing detail.(2) I could have monitored the DVO CTAF while flying over the airport; as it does appear the parachute jump was announced on that frequency. However; I was flying at 2;400 feet; had been in contact with NORCAL TRACON; and had just canceled flight following to begin monitoring the AWOS and CTAF for my destination airport which was coming up shortly. Overall; I think this is a situation which; although rare; has the potential to be catastrophic and yet is not something that is marked or communicated to pilots with the urgency it likely deserves.




Synopsis: GA pilot reported encountering skydivers near DVO. The sectional and terminal charts do not indicate skydiving is present at DVO. A NOTAM was posted only 90 minutes before jump operations began and ATC; possibly unaware; gave no warning of the activity.