NAVWEPS 00-8OT-80  AIRPLANE PERFORMANCE  If the airplane were to hold the same angle of  bank at 500 knots (TAS), the turn radius  would quadruple (r=22,200 ft.) and the turn  rate would be one-half the original value  (ROT=2.19 deg. per sec.).  Values of turn radius and turn rate versus  velocity are shown in figure 2.29 for various  angles of bank and the corresponding load  factors. The conditions are for the steady,  coordinated turn at constant altitude but the  results are applicable for climbing or descend-  ing flight when the angle of climb or descent  is relatively small.  While the effect of alti-  tude on turning performance  is not immediately  apparent from these curves, the principal effect  must be appreciated as an increased true air-  speed (TAX) for a given equivalent airspeed  (EAS).  important-if  not more important-as  the  increased stall speed in turning flight.  It is  important also that any turn be well coordi-  nated to prevent the increased drag attendant  to a sideslip.  TURNING  PERFORMANCE.  The hori-  zontal component of lift will equal the centrif-  ugal force of steady, turning flight.  This fact  allows development of the following relation-  ships of turning performance:  turn radius  where  P  r= 11.26 tan 6  ROT= 1,091 tan rb  V  r= turn radius, ft.  ti = bank angle, degrees  I ’ = velocity, knots (TAX)  ROT=rate of turn, degrees  per sec.  $= bank angle, degrees  v=velocity,  knots, TAS  ttrrn rate  where  TACTICAL PERFORMANCE.  Many tac-  tical maneuvers require the use of the maxi-  mum turning capability of the airplane. The  maximum turning capability of an airplane will  be defined by three factors:  (1) Maximum lift capability. The combi-  nation of maximum lift coefIicient, C,,=,  and wing loading, W/S, will  define the  ability  of the airplane to develop aero-  dynamically the load factors of maneuvering  flight.  These relationships define the turn radius, I,  and rate of turn, ROT, as functions of the two  principal variables: bank angle, +, and velocity,  I’ (TAX).  Thus, when the airplane is flown  in the steady, coordinated turn at specific  values of bank angle and velocity, the turn  rate and turn radius are fixed and independent  of the airplane type.  As an example, an air-  plane in a steady, coordinated turn at a bank  angle of 45’ and a velocity of 250 knots (TAS)  would have the following turn performance:  (2) Optrating ftrcngth limits will define the  upper limits of maneuvering load factors  which will not damage the primary struc-  ture of the airplane.  These limits must not  be exceeded  in normal operations because  of  the possibility  of structural damage or  failure.  (3) Thwt or power limits will define the  ability of the airplane to turn at constant  altitude.  The limiting condition would al-  low increased load factor and induced drag  until the drag equals the maximum thrust  available from the powerplant.  Such a case  would produce the maximum turning capa-  bility for maintaining constant altitude.  The first illustration of figure 2.30 shows  how the aerodynamic and structural limits  and  = 5,550 ft.  ROT=(I,091)(1.000)  250  -4.37 deg. per sec.  178 