【正文】 based upon the aerodynamic analysis. Tav was calculated using equation of Raymer [10]: 312???????????? ????????? b h pDNb h pTpeslav?? Equation 22 In Equation 22 bhp, ρ, and ρsl have been previously discussed. Ne is the number of engines in the aircraft (one) and Dp is the propeller diameter of ft (74 in.) as determined by the propeller analysis. Turn load factor was calculated using an altered version of Raymer’s equation to account for a nonsymmetric airfoil: 2m i n_m i n_02 221d r a gLd r a gLLD CCCKCSWVn ?????? ? Equation 23 Where ρ is the density at cruise altitude, V is the cruise speed, W/S is the wing loading, CD0 is the zero lift drag coefficient , CL is the coefficient of lift during cruise, and CL_mindrag is the minimum drag coefficient of lift. All of these values have been previously discussed. The final constraint stall was calculated in a different manner. Since stall speed is only a function of air density, CL_max, and wing loading, the wing loading at which the plane stalled at 57 kts at sea level could be calculated directly from the equation: 2m a x_21 s t a l lslLs t a l l VCSW ????????? ? Equation 24 57 kts was chosen as Team V’s designed stall speed in order to leave room for error and still meet the FAR requirement of a 61 knot stall speed. Once the wing loading for stall was calculated, it was plotted as a vertical line on the carpet plot. For pleteness, landing distance, best range cruise speed, and best range cruise distance are also calculated in the sizing code. Best range cruise distance is calculated because the 600 nmi range is not the best range distance, but the range for a cruise at 150 kts. Team V。 Team V。 17 Table 3 – Sizing Code Notable Inputs/Outputs P a r a m a t e r V a l u e u n i tG T O W 2 6 1 8 . 8 l b sC r u i s e s p e e d 150 k t sS t a l l S p e e d 57 k t sE n d u r a n c e 0 . 7 5 hrA s p e c t R a t i o ( A R ) 8 . 2C r u i s e A l t i t u d e 8000 ftD i v e r t A l t i t u d e 2020 ftC r e w W e i g h t 150 l b sP a y l o a d W e i g h t 450 l b sCD0 0 . 0 2 3C L m a x 1 . 6C L m i n d r a g 0 . 0 7 5R a n g e 600 miE m p t y W e i g h t F r a c t i o n 0 . 6 1 9 5 3F u e l W e i g h t F r a c t i o n 0 . 1 5 1 3 5F u e l W e i g h t 3 9 6 . 3 8 l b sE m p t y W e i g h t 1 6 2 2 . 6 l b sW i n g s p a n 3 4 . 8 3 3 ftW i n g a r e a 1 4 7 . 9 6 s q f tW i n g l o a d i n g ( W / S ) 1 7 . 7 l b s / s q f tB a l e n c e d F i e l d L e n g t h 1 4 7 7 . 9 ftL a n d i n g D i s t a n c e 1 4 1 0 . 5 ftB e s t R a n g e C r u i s e S p e e d 1 0 2 . 2 9 k t sB e s t R a n g e C r u i s e D i s t a n c e 1 1 3 7 . 8 k m i B e s t C l i m b r a t e 1 4 6 8 . 8 f p mC D c l i m b 0 . 0 6 2 7 2 4C D c r u i s e 0 . 0 2 9 6 6 4C D m i n t h r u s t 0 . 0 5 8 4 5 1C L c l i m b 0 . 6 3 0 2 6C L c r u i s e 0 . 2 9 5 4 9C L t a k e o f f 0 . 4 6 4 1 5C L m i n t h r u s t 0 . 6 8 7 1 9L / D C l i m b 1 0 . 0 4 8L / D C r u i s e 9 . 9 6 0 8L / D m i n t h r u s t 1 1 . 7 5 7p o w e r t o w e i g h t 0 . 0 7 6 3 6 6t h r u s t t o w e i g h t 0 . 1 2 6 8 3S F C 0 . 2 3 4 8 6P r o p D i a m e t e r 6 . 1 6 6 7 ftP r o p E f f i c i e n c y C l i m b 0 . 7 6P r o p E f f i c i e n c y C r u i s e 0 . 8 6V e r t i c a l T a i l a r e a 1 0 . 5 0 6 s q f tH o r i z o n t a l t a i l a r e a 1 7 . 9 2 9 s q f tT u r n n v a l u e 2 . 0 2 6 47 5 % P o w e r S p e e d 1 6 2 . 6 6 k t sF u e l V o l u m e 5 3 . 9 7 6 galO s w a l d 39。 10 ???????? ??????????? ??????????? ????? 222 2 12 12 1 t a k e o f ft a k e o f fc r u i s ec r u i s ee VghVghVghh Equation 10 where h is altitude, g is the gravity constant, and V is speed. Note that Vtakeoff is calculated as times stall speed. This is conservative since it does not consider the acceleration that will occur as the plane climbs to the 50 foot altitude accounted for in the takeoff fuel weight fraction equation. The average climb speed is calculated using the Raymer’s equation : 02limDbc CKSWV ??? ? Equation 11 where W/S is wing loading (an input parameter), ρ is air density at sea level, CD0 is the zero lift drag coefficient, and K is the aerodynamic constant. CD0 was calculated to be in the aerodynamic analysis. K was calculated using the equation: eARK ???? 1 Equation 12 Where AR is the aspect ratio and e is the Oswald Efficiency Factor. The Aspect ratio is an input parameter which was chosen through the use of carpet plots (discussed later) and the Oswald Efficiency Factor was determined as a function of aspect ratio via a curve fit of CMARC analysis data for the plane which yielded the equation: 4 3 5 2 6 ??? ARe Equation 13 34WW represents the fuel weight used during the cruise segment and is calculated using the Breguet range equation (also Raymer ): ??????????????????????DLVCRWWii ex p1 Equation 14 where R is range (less the distance traveled during climb), C is SFC (same as before), V is cruise speed, and L/D is the lift to drag ratio at cruise conditions. Distance traveled during the range segment is calculated by subtracting the average climb velocity multiplied by the time it will take to reach 8000 ft at a climb rate of 700 fpm from the design mission’s range of 600 nmi. Cruise speed is set at the design cruise speed of 150 kts. Cruise L/D was calculated in the same manner as it was for climb, except that the density and speed used were the cruise condition values, and not those of climb. 45WW represents the fuel used during descent and is assumed to be . This was approximated by estimating the fuel usage per minute and multiplying it by a