Date: 201908
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Challenger 605
Operator: Corporate
Operating under: Part 135
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Reporter organization: Corporate
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Situational Awareness; Time Pressure; Workload
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Other Arrival Cargo Unloading
Result: General None Reported / Taken
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: The lead passenger arrived 45 minutes earlier than scheduled and informed us the other passenger; as well as the bags; would arrive 5 minutes later. This resulted in myself completing the 'cockpit task' while the other crew member greeted and loaded the baggage. Upon arrival; I went to the baggage compartment to assist in offloading to the other crew member. This is when I discovered the two boxes labeled with Hazmat stickers. Moving forward I will assist in the loading of the baggage as a crew to ensure only allowed items are loaded.


Second narrative: Two lithium batteries used in electric bicycles were accidentally carried aboard Aircraft X from ZZZ to ZZZ1. One passenger arrived 45-50 minutes prior to scheduled departure and the second passenger arrived shortly thereafter in a vehicle with baggage; which was pulled plane-side. Due to the early arrival of the passengers; the PIC was busy in the cockpit setting up the flight plan and receiving clearance as I; the SIC; helped the passengers aboard and loaded the baggage. The baggage consisted of two rolling suitcases; a few hanging garment bags; several small soft tote bags; one large; flat; partially-opened cardboard box that contained pictures/art; and two sealed cardboard boxes. I placed one suitcase and a couple of hanging bags inside the baggage compartment from the ground; then walked through the cabin to the baggage compartment so that I could arrange baggage as the line crew transferred the remainder from the vehicle to the plane. The baggage compartment was not filled to capacity and the two sealed cardboard boxes and other soft bags were placed on the floor near the door in a suitable position by the line crew. Throughout this process; I did not notice the Hazmat labels on the boxes due to their relative position with soft bags around them and my attention to arranging the other baggage. The flight landed uneventfully and I reported the discovery to the director of operations as soon as possible. Moving forward; I will not allow my familiarity with any passenger nor my haste to accommodate an earlier than scheduled departure to supersede the crew's duty to inspect all items loaded upon the aircraft.


Synopsis: CL-600 flight crew reported two passenger Hazmat boxes were detected during cargo unloading at destination. No required Dangerous Goods documents were provided to flight crew prior to departure.