Get The Lead Out
There is a fundamental reason we perform preflight run-ups and engine checks before takeoff: It is a whole lot better to find problems at 1G, 0 feet agl and 0 knots airspeed than it is while airborne. Making sure a powerplant will work as we intend before taking off is just good airmanship. A good run-up doesnt mean everything is perfect, however, and we train for airborne engine problems, including full use of its controls and instruments.