Geometric and Performance Data of a Vigilante RA-C5 Aircraft

A three-view diagram of an RA-C5 Vigilante aircraft is shown in Figure 9.16. The following pertinent geometric and performance parameters are from [3]: two crew; engine: 2 x turbo-jet GE J-79-8(N), 75.6 kN; wingspan: 16.2 m; length: 22.3 m; height:

5.9 m; wing area: 65.0 m2; start mass: 27,300 kg; max speed: Mach 2+; ceiling: 18,300 m; range: 3,700 km; armament: nuclear bombs and missiles (only a clean configuration is evaluated).

Fuselage

• fuselage length = 73.25 ft

• average diameter at the maximum cross-section = 7.785 ft

• fuselage length/diameter = 9.66 (fineness ratio)

• fuselage upsweep angle = 0 deg

• fuselage closure angle « 0 deg

Wing

• planform reference area, SW = 65.03 m2 (700 ft2)

• span = 16.2 m (53.14 ft)

• aspect ratio = 3.73 deg

• t/c = 5%

Table 9.16. Bizjet total aircraft drag coefficient, CD CL 0.2 0.3 0.4 0.5 0.6 0.7 CDpmin ACDp (Table 9.6) 0.0003 0.00006 0 0.0205 (Table 9.5) 0.0006 0.0020 0.0040 Cmt (Table 9.7) 0.0017 0.00382 0.0068 0.0106 0.0153 0.0206 Total aircraft CD @ LRC 0.0225 0.02438 0.0273 0.0317 0.0378 0.0451 Wave drag, CDw (Figure 9.9) 0.0014 0.00170 0.0020 0.0025 0.0032 0.0045 Total aircraft CD @ HSC 0.0240 0.02618 0.0293 0.0342 0.0410 0.0496

Figure 9.14. Drag polar of Figure 9.1 plotted C2l versus CD

• taper ratio, X = 0.19

• camber = 0

• wing MAC = 4.63 m (15.19 ft)

• А/ = 37.5 deg

• Ale = 43 deg

• root chord at centerline = 6.1 m (20 ft)

• tip chord = 1.05 m (3.46 ft)

Empennage

• V-tail

• Sv = 4.4 m2 (47.34 ft2)

• span = 3.6 m (11.92 ft)

• MAC = (8.35 ft)

• t/c 4%

• H-tail

• Sh = 6.063 m2 (65.3 ft2)

• span = 9.85 m (32.3 ft)

• MAC = (9.73 ft)

• t/c = 4%

Nacelle/pylon (the engine is buried in the fuselage – no nacelle pylon)

• aircraft cruise performance, where the basic drag polar must be computed

• drag estimated at cruise altitude = 36,152 ft

• Mach number = 0.6 (has compressibility drag)

• ambient pressure = 391.68 lb/ft2

• Re/ft = 1.381 x 106

• design CL = 0.365

• design Mach number = 0.896 (Mcrit is at 0.9)

• maximum Mach number = 2.0