Date: 201907
Local time of day: 0601-1200
Location: TJSJ, PR
Flight conditions: VMC
Aircraft: Cessna 402/402C/B379 Businessliner/Utiliner
Operator: Air Taxi
Operating under: Part 135
Flight plan: VFR
Mission: Passenger
Flight phase: Cruise
ATC / advisory: Center TJSJ
Second aircraft: King Air C90 E90
Reporter organization: Air Taxi
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Communication Breakdown
Second reporter function: Pilot Not Flying
Anomaly: ATC Issue All Types; Conflict NMAC; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure; Airspace Structure
Primary problem: Procedure

Narrative: We were in cruise 3 miles north of the shoreline near TJAB airport. We usually stay north of the shoreline due to parachute activity at TJAB going to and from TJSJ and TJMZ. We normally get advisories of jumping activity and we tell them we are staying north or San Juan Center gives us direction to stay away from the area. Today; we were at 4;500 MSL in cruise 3 miles north of the shore heading west bound. We had flight following squawking XXXX from TJSJ in route to TJMZ. We were on with San Juan Departure. We heard a King Air at 10;000 [feet] reporting jumper away at the same time we were passing by. I was looking out my window to see if we could see them. No visual contact. We did not get any traffic advisories from ATC. Suddenly; I spotted the King Air at my 7 to 8 o'clock about 500 feet above me heading right for me but in a turn back to the coast line. I was close enough to see the tail number. I took immediate action and turned right to give us some space. I do not believe the King Air saw us as his belly was mostly pointing to us. A few moments later; ATC switched us over to San Juan Center. We did not mention it over the frequency; but some of our passengers noticed how close the plane was. It was VFR; however; this plane was also on frequency and squawking a code and no advisories from them. We were extremely close. The flight ended in safety but wanted to file a report anyway.  No ATC advisories. Maintained VFR - visually scanning for other aircraft.


Second narrative: Cruise flight enroute to ZZZZ from TJSJ approximately 3nm NNW of Arecibo 4;500 msl. In contact with San Juan Departure and shortly thereafter San Juan Center for VFR Flight Following/Advisories with a beacon code. We received this beacon code on the ground prior to taxiing for departure to depart the Class C VFR and requested advisories with that. Crew is familiar with parachute activity at Arecibo and Center frequently advises us to stay north or south of the jump area for this activity in which we comply by staying north of Arecibo out over the water as it typically is slightly cooler therefore smoother and lacks the cumulus clouds that build over the island. I am familiar with the jump plane and its call sign as we usually hear them all day on our schedule route on the same Center frequencies as well as 122.8 the CTAF for Arecibo and Mayaguez so we hear that whilst monitoring enroute and at our destination; it was broadcasting itself and ATC was responding to King Air. Shortly prior to our encounter; we heard '[King Air] Jumpers Away Ten Thousand Descending'. Actively watching for VFR separation with a known aircraft in the vicinity as well as other; Pilot Flying and myself as Pilot Monitoring were scanning over Arecibo to our left. Pilot Flying spotted the rapidly descending and turning King Air and initiated a turn northbound away from the trajectory of the King Air. I caught glimpse of the aircraft shortly prior to its turning descent through our altitude and abeam our left wing and could identify it as a King Air even from the right seat. From my perspective he would have never been able to see us as he was in a steep enough turn exposing only his underside to us making it impossible to see and avoid us. By chance; his turn was tight enough to clear us and his trajectory continued southerly until he was headed away from us towards Arecibo. At no point through this event did ATC advise of traffic; or a suggested heading; turn; or descent. Shortly after the close call; ATC advised contact Center. We did not query ATC of the incident. We switched frequencies and continued to ZZZZ after documenting our time and location. No abnormalities resulted from this event. Flight landed safely at its destination ZZZZ.  Lack of diligence on behalf of ATC. Aggressive maneuvering on behalf of skydive aircraft.


Synopsis: C402 flight crew reported a NMAC with a Beechcraft King Air.