Turn Lift Requirements
As the bank angle increases, the amount of pull required to maintain level flight increases rapidly. It is not possible to maintain level flight beyond a given bank angle because the wings cannot produce enough lift. An attempt to fly beyond this point will result in either a stall or a descent.
Physiologically speaking, the most important part of a turn is the necessity to pull "Gs". As the back pressure is increased to maintain level flight, the increased force is felt as an increase in "G" level. In a 30 degree bank, 1.2 G is required to maintain level flight. The G level increases rapidly with an increase in bank; at 60 degrees, it goes to 2.0 G, and it takes 9.0 G to fly a level 84 degree bank turn. As long as there is enough airspeed, the G level can be increased in any bank angle by pulling back on the stick.
Finishing the turn, a simple matter of leveling the wings by using the ailerons and coordinated rudder, takes time; the airplane continues turning until the wings are level, so the roll-out must be started a little prior to reaching the desired heading. Back-stick pressure must also be released as bank decreases or the aircraft will climb.
Maneuverability
Airplanes are not limited to being a relatively fast means of getting somewhere. Long ago thrill-seeking pilots discovered that aircraft have the potential for providing loads of fun while getting nowhere fast. Aerobatics are an essential skill for fighter pilots; and the training that it gives to pilots in position orientation and judgment is considered so vital that a great deal of time is spent teaching these maneuvers. Maneuverability is defined as the ability to change the speed and flight direction of an airplane. A highly maneuverable airplane, such as a fighter, has a capability to accelerate or slow down very quickly, and also to turn sharply. Quick turns with short turn radii place high loads on the wings as well as the pilot. These loads are referred to as "g forces" and the ability to "pull g's" is considered one measure of maneuverability. One g is the force acting on the airplane in level flight imposed by the gravitational pull of the earth. Five g in a maneuver exerts 5 times the gravitational force of the earth.
Maneuverability
Aileron Roll The aileron roll is simply a 360 degree roll accomplished by putting in and maintaining coordinated aileron pressure. The maneuver is started slightly nose high because, as the airplane rolls, its lift vector is no longer countering its weight, so the nose of the airplane drops significantly during the maneuver. Back stick pressure is maintained throughout so that even when upside down, positive seat pressure (about 1 G) will be felt. As the airplane approaches wings-level at the end of the maneuver, aileron pressure is removed and the roll stops.