Sir - In reply to the letter "Will we see turns without banking?" from D F Newland (Flight International, 20-26 November, P74), the reasons against flat turns are:
the biological control unit (the pilot) would pass out because of the high lateral loading;
to maintain equilibrium in a turn, the centrifugal force on the aircraft must be reacted by an equal inwardly acting force. This is provided by the angle of bank, which generates an inward force by "tilting" the lift from the wing.
To try to generate this inward force in a flat turn would require lateral thrusters forward and aft of the centre of gravity - not a very efficient system.
P GAMBARDELLA
Farnborough, Hampshire, UK
Source: Flight International
