Question: How do you know when you have a positive rate upon takeoff?
— Rhett Butler Sr., Chesapeake, Va.
Answer: There are several ways. You can feel the wings creating lift and lifting the airplane off the ground. Once airborne, often you can feel the main gear struts “bottom out” as they fully extend.
Pilots also monitor the altimeter, which is increasing, and the vertical speed indicator for a positive climb.
Q: What lifts the plane off the ground on takeoff, the pilot using a control or just reaching a certain speed for lift?
— Victor Gust, Naples, Fla.
A: Once the airplane has accelerated to the proper speed, known as rotation speed or Vr, the pilot commands the elevators on the tail to raise the nose. Small airplanes will fly off, but jets and larger airplanes have to be commanded to raise the nose.
Q: How is the nose of an airplane lifted during takeoff?
— FHM
A: The pilot applies backpressure to the yoke or side stick, causing the elevator in the tail to force the tail downcausing the nose to rise.
Q: Why, on the takeoff roll, is there a call out for 80 knots? Is that the speed the rudder becomes effective?
—Skip E., Los Angeles
A: The 80-knot call is to ensure that both airspeed indicators are functioning and indicating properly. The rudder is becoming effective at that speed, too.
Q: Do any runways come to mind that are too short to abort a takeoff having almost reached takeoff speed?
— Jeff, Stuart, Fla.
A: No, before every takeoff the pilots or specially trained ground staff calculate the maximum weight allowed, ensuring the capability to safely stop if necessary or to fly and clear obstacles. This weight changes due to aircraft type, temperatureand runway conditions.
When a pilot begins the takeoff roll, he/she knows that it is possible to stop up to decision speed (V1) and then to continue the takeoff and climb safely.
John Cox is a retired airline captain with US Airways and runs his own aviation safety consulting company, Safety Operating Systems.
