Page 460 - Aircraft Stuctures for Engineering Student

Problems 44 1
P.10.18 A three-flange wing section is stiffened by the wing rib shown in
Fig. P.lO.18. If the rib flanges and stiffeners carry all the direct loads while the rib
panels are effective only in shear, calculate the shear flows in the panels and the
direct loads in the rib flanges and stiffeners.
Ans. ql = 4.0 N/mm, q2 = 26.0 N/mm, q3 = 6.0 N/mm.

Pz in 12 = -P3 in 43 = 1200N (tension), P5 in 154 = 2000N (tension),
P3 in 263 = 8000 N (compression), P5 in 56 = 12 000 N (tension),
P6 in 263 = 6000 N (compression)

2 1

8000 N
Fig. P.10.18

P.10.19 A portion of a wing box is built-in at one end and carries a shear load of
2000N through its shear centre and a torque of 1000 Nm as shown in Fig. P.10.19.
If the skin panel in the upper surface of the inboard bay is removed, calculate the

Fig. P.10.19