Just keeping it local, speeds approximate and in knots:
At the Equator: 970kn
Earth orbital speed around Sun: 58,000kn
Sun orbital speed around galaxy: 447,000kn (Really?)
Less local:
Galaxy through space: 1,166,310kn
So, when you make a 180 in your 50kn glider you change from going forwards at over a million knots to backwards at the same speed.
Better lock your hold on those flight controls!
p.s. Foregoing a bit of Shiraz induced reductio ad absurdum - did you notice?