Just finished a T34 plane with pulse jet engine.  The Plane was a kit from Robert Bolton.  The jet engine was from Hobby King.

I looked at the pictures of the jet model and was having an ides to see how fast you can really go. In speed events in RC it is not uncommon to go 160 to 212 mph this is with a 1/2A type model with about 70/85 seconds of power.
A ducted fan with a 12 blade fan and a 6 cell battery with a motor turning about 60K rpm should satisfy anyone urge to go really fast. Those D.F motors are capable of that rpm.
So it is just a little meandering in imagination .