After 2 Chainz gets on board, the airplane immediately starts to roll down the runway for take-off. Even if the #2 engine was already running (unlikely), it would take several minutes for the pilots to start the #1 engine, run the checklists and pre-flight checks, and taxi to the runway. Also, the pilots would ensure all of the passengers had their seat belts fastened before the aircraft even began to start its taxi.
When the plane goes down they land in Kansas. The pilot says go Chiefs. The Chiefs are an American football team that actually plays in Kansas City, Missouri.