As many of you know I am a flight dispatcher. One of the requirements of our job is to do an annual familiarization flight on our aircrafts to get a better understanding of how our job works together with the pilots in order to ensure you have a safe flight.
Last year, I had the opportunity to fly from Edmonton to Yellowknife, Norman Wells, Inuvik, and return. This run is busy for both passenger and cargo travel. As a result, we flew combi aircrafts which carry both cargo and passengers on the upper deck. This particular 737-200 aircraft was in a 3 pallet 34 passenger configuration on this specific flight, but can be changed into any combination from all passengers to 6 pallets and 6 seats.
As a result of the cargo being on the upper deck, the company uses the rear L2 door for boarding. Flying up to the arctic also creates the challenge of needing stairs as there are no bridges for passengers to board. The solution to this is flying with stairs built into the aircraft, known as air stairs.
This is a video of how the rear air stairs open and close on a 737-200 aircraft.