I'm designing a test fixture and need a compact coaxial electric motor. The motor drives two counter rotating fans with tip speeds up to 650 fps (desired), 500 fps (required). The fan diameter has not been selected, but is between 2 to 3 ft. Initial estimates suggest that the total fan power will be below 10 hp. The motor may be water cooled. I'm looking for recommendations for a supplier for this motor. I see that a MIT student used Maxxon motors for a coaxial drive on a dual prop ducted propeller and I have contacted them.