Figure 15-12.  Thrust and power required curves (jet aircraft vs. propeller-driven aircraft). Thrust required Airspeed 4,000 3,000 2,000 1,000 0 Power required Airspeed 4,000 3,000 2,000 1,000 0 0 100 200 300 400 500 A Jet Aircraft 0 100 200 300 400 500 B Propeller-Driven Aircraft I n d u c e d d r a g P a $_{r}$a s i t e d r a g Total drag L/D$_{MAX}$ Minimum drag or L/D$_{MAX}$ Total power required Minimum power required P o w e r r e q u i r e d P a r s i t e p o w e r e q u i r e d Lift Coefficient Angle of Attack Sweptwing S t $_{r}$a i g h t $_{ }$w i n g Figure 15-14.  Stall progression—typical straight wing airplane. Figure 15-13.  Stall versus angle of attack—sweptwing versus  straight wing. 15-12 stall.  [Figure 15-14]  The conventional straight wing airplane  conforms to the familiar nose-down pitching tendency at the  stall and gives the entire airplane a fairly pronounced nose- down pitch. At the moment of stall, the wing wake passes  more or less straight rearward and passes above the tail. The  tail is now immersed in high energy air where it experiences  a sharp increase in positive AOA causing upward lift. This  lift then assists the nose-down pitch and decrease in wing  AOA essential to stall recovery. On a conventional straight wing/low tailplane airplane, the  weight of the airplane acts downwards forward of the lift  acting upwards, producing a need for a balancing force acting  downwards from the tailplane. As speed is reduced by gentle  up elevator deflection, the static stability of the airplane  causes a nose-down tendency. This is countered by further up  elevator to keep the nose coming up and the speed decreasing.  As the pitch attitude increases, the low set tail is immersed  in the wing wake, which is slightly turbulent, low energy  air. The accompanying aerodynamic buffeting serves as a  warning of impending stall. The reduced effectiveness of the  tail prevents the pilot from forcing the airplane into a deeper  In a sweptwing jet with a T-tail and rear fuselage mounted  engines, the two qualities that are different from its straight  wing low tailplane counterpart are the pitching tendency 