Aircraft Performance

Explain your idea about airplane performance.

Show that at maximum aerodynamic efficiency, the zero-lift drag equals induced drag.

Consider an airplane whose weight is $38220 \text{ N}$, wing area is $27.3 \text{ m}^2$, aspect ratio is $7.5$, Oswald efficiency factor is $0.9$, and parasite drag coefficient is $0.03$. Determine the thrust required to fly at a velocity of $340 \text{ km/h}$ at standard sea level where $\rho = 1.23 \text{ kg/m}^3$.

Define the rate of climb ($R/C$) of an airplane and show that $R/C = \frac{\text{Excess Power}}{\text{Weight of the airplane}}$

Differentiate between service ceiling and absolute ceiling.

A light aircraft of mass $3500 \text{ kg}$ descends with engines off at a glide angle of $4^\circ$ from an altitude of $5000 \text{ m}$. Determine the drag and lift components that act during the glide, and the range covered from the start of the glide to touchdown.

Explain turning and pull-up maneuvers with necessary diagrams and show that both the turning and pull-up maneuvers require more lift than that of level flight.

Use the $V$-$n$ diagram as shown in Fig. 3(b) in the T-38 data to answer the following:

• What is the corner velocity for this aircraft at standard sea level?
• What is the stall limit at 6.5g when the aircraft flies at an altitude of $15000 \text{ ft}$?
• What is the instantaneous load factor at sea level and Mach number 0.8?
• What are the positive and negative structural limits for this aircraft at standard sea level?
• What is the maximum Mach number at an altitude of $15000 \text{ ft}$?