Black ovel or round flying object

Yesterday I was driving to band rehearsal @ 3:29 PM on HWY 9 About 1 mile west of Lake Stevens .  I'm traveling 55mph. An object in the sky caught my eye. Flying in the same direction as me moving horizontally slightly diagonally to the left.  It was just above the tree line aprox 175ft. in altitude. It passed me and disappeared over the tree line 1\4 mile ahead of me on the left side.  Approx size was 10-15 ft in length and solid black in color (Sky was clear & sunny ).  Shape was round or oval.
Now as a drone and R/C pilot for many years I am familiar with judging height and speed of the aircraft I fly. I was traveling at 55mph. The unknown aircraft passed me at at least double my speed. My fastest drone will do 45mph. I know of no drone that surpasses 65mph (small racing drones). So tell me, what has no wings, no props, no vertical stabilizer and no visible form of propulsion. I'll grant you a round disc like a frisbee is an airfoil and will fly. Also it was silent.
This was not a parachute or hang glider or any thing I've ever seen .
Idea's?????