Exercise 8

Exercise 8: Range/Endurance

Givens Conditions:
Gross Weight for Beginning of Cruise = 300,000 lbs
Gross Weight at End of Cruise = 200,000 lbs
Altitude = FL350
Standard Conditions
Wing Area = 3050 ft2
Wing Span = 156 ft
Wing Efficiency = .75
CDp = 0.0119
Twin turbofan engines
Figure 2.1
Figure 6.5
Figure 13.2
No need to take into account Temperature Ram Rise

1. Find Equivalent Airspeed, True Airspeed, and Mach for best range at FL350 and Sea Level at W = 300,000 lb. (Use Figure 13.2 and Equations 4.6, 3.8. and 3.4.)

2. Assuming constant altitude, find the best Range Equivalent Airspeed, True Airspeed, and Mach at the end of cruise for W = 200,000 lb at FL350, and Sea Level. (Use Figure 13.2 and Equations 4.6, 3.8, and 3.4.)

3. Find Range (nm) at Sea Level and at constant FL350. Assume altitude remains constant, AOA remains constant, and Airspeed varies (Use Equation 13.1.)

4. Compare specific ranges at FL350 W = 300,000 lb and W = 200,000 lb. (Use Equation 12.2.)

5. Find Equivalent Airspeed, True Airspeed, and Mach for best endurance at FL350 and Sea Level at W = 300,000 lb.

6. Assuming Constant Altitude, what is best Endurance Equivalent Airspeed, True Airspeed, and Mach at W = 200,000 lb?

7. Find Best Endurance (hours) at FL350 (use Equation 13.9) using the same gross weight differences.

8. How much does it cost a B-737 to carry an extra 10,000 lb of fuel for a standard 500 nm trip according to the textbook? (See Figure 12.5.)