Aside from the apparent visual differences, how different are they. Same engines? Rotors? Are 46 pilots qualified for the Chinook?
The CH-47 is a much bigger, heavier, and more powerful aircraft. Both have the same origins, as the YHC-1A competing for an Army contract in 1958. The Army deemed the YHC-1A as too light for it’s needs as a heavy troop transporter, and choose the bigger test model instead (HC-1B). The HC-1B was developed into the the CH-47 Chinook for the Army. The Marines, however liked the YHC-1A and developed it into the CH-46 Sea Knight.
The CH-47 is larger overall and has a max takeoff weight of 50,000 lbs and a capacity of nearly 60 troops. The CH-46’s max takeoff weight is around 26,000 lbs and can carry about 25 troops.
Also different engines, different rotors, etc. Aside from having the same manufacturer and using the same tandem design philosophy, completely different aircraft.
They are very different aircraft.