Its all well and good having a time ship that can turn invisible in order to keep your time-travelling antics top secret, but why only turn the invisibility on when the ship is stationary? It seems a little bizarre and a headscratcher to see the Waverider fully visible when taking off or when its coming through the skies to land. You have to think WTF is the point of keeping the ships presence hidden when its grounded if anyone and everyone can easily see the Waverider as soon as it leaves the ground.