Effective Aspect Ratio for Single Vertical Tail

image\MISC0000.gif

 

For single vertical tail, the effective aspect ratio is given by:

 

image\MISC0068_wmf.gif

 

The ratio of vertical tail aspect ratio in the presence of fuselage to that of an isolated vertical tail is found from Figure 10.14 in Airplane Design Part VI. It is a function of Z-location of the vertical tail tip relative to the fuselage centerline, fuselage depth in region of vertical tail and vertical tail taper ratio.

 

image\MISC0069_wmf.gif

 

Note:  The variable symbol used in Figure 10.14 of Airplane Design Part VI is different from the symbol used in the program. The symbols for the same variable are given by the following:

 

Airplane Design Part VI

image\ebx_1134313236.gif

AAA program

image\ebx_-847510456.gif

 

The Z-location of the vertical tail tip relative to the fuselage centerline is given by:

 

image\zv_eqn_shg.gif

 

The vertical tail span is given by:

 

image\MISC0074_wmf.gif

 

The taper ratio of the vertical tail extended to the fuselage centerline is computed from:

 

image\lambda_prime_v_shg.gif

 

The aspect ratio of the vertical tail extended to the fuselage centerline is computed from:

 

image\MISC0076_wmf.gif

 

The area of the vertical tail extended to the fuselage centerline is calculated from:

 

image\S_prime_v_shg.gif

 

The vertical tail root chord is given by:

 

image\MISC0078_wmf.gif

 

The correction factor accounts for the relative size of vertical tail and horizontal tail is found from Figure 10.16 in Airplane Design Part VI. It is a function of horizontal tail area and the area of the vertical tail extended to the fuselage centerline:

 

image\MISC0079_wmf.gif

 

Note:  The variable symbol used in Figure 10.16 of Airplane Design Part VI is different from the symbol used in the program. The symbols for the same variable are given by the following:

 

Airplane Design Part VI

image\ebx_350752420.gif

AAA program

image\ebx_1580918790.gif

 

The ratio of vertical tail aspect ratio in the presence of fuselage and horizontal tail to the vertical tail aspect ratio in the presence of fuselage alone is found from Figure 10.15 in Airplane Design Part VI. It is a function of the relative position of horizontal tail and vertical tail, the Z-location of the horizontal tail root chord relative to the fuselage centerline and the Z-location of the vertical tail tip relative to the fuselage centerline:

 

image\MISC0083_wmf.gif

 

Note:  The variable symbol used in Figure 10.15 of Airplane Design Part VI is different from the symbol used in the program. The symbols for the same variable are given by the following:

 

Airplane Design Part VI

image\ebx_1134313236.gif

AAA program

image\ebx_-847510456.gif

 

The Z-location of the aerodynamic center fo the horizontal tail relative to the fuselage centerline is given by:

 

image\MISC0089_wmf.gif

 

Note:

 

image\MISC0090_wmf.gif

 

The horizontal distance from the leading edge of the vertical tail, at the spanwise station at which the vertical tail intersects with horizontal tail, to the horizontal tail aerodynamic center is calculated from:

 

image\MISC0091_wmf.gif

 

See: Aerodynamic Center Locations for details on horizontal tail aerodynamic center.

 

 

The vertical tail chord length at the spanwise station at which the vertical tail intersects with horizontal tail is calculated from:

 

image\MISC0092_wmf.gif

 

image\MISC0087_wmf.gif

 

See: Effective Aspect Ratio for Twin Vertical Tail