Tranquillus, Analysis Data Item Vol. 1

The increment in wing chord due to flap deflection in terms of flap chord is found from Figure G-7 in Synthesis of Subsonic Airplane Design (E. Torenbeek) as a function of flap deflection angle and the flap type:

c w  f  f , Type  cf

Eqn. (5)

The ratio of flapped wing area to wing area is calculated from:

Swf





of





  if  2  1   w   o f   i f



Eqn. (6)

Sw 1  w Note: The wing lift curve slope at M1 = 0, including flap effects is found by substituting the wing lift curve slope at M1 = 0, without flap effects into the equations above. cl 



cl M 0 1 M

Eqn. (7)

2

Horizontal tail lift curve slope:

The horizontal tail lift curve slope is calculated from:

C Lh  C Lh 

 exp

.

S hexp Sh

K

h( B)

 K B(h) 

Eqn. (8)

The horizontal tail-body interference factor is found from DATCOM Figure 4.3.1.2-10.

The exposed horizontal tail lift curve slope may be estimated from: 2ARhexp f gaph Eqn. (9) C Lh exp  1 2 2  AR 2  2  tan  c     hexp  2h  2 1  4 2 2        k     The horizontal tail gap correction factor is found from:   x  f gaph  f  ARh ,  gap  ,  gap   Eqn. (10) C  C e  e   The Prandtl-Glauert transformation factor is derived from:

  1  M 12

Eqn. (11)

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