Integrated Climb Performance (Bizjet)

Integrated climb performance is not a requirement for substantiation – it is used to obtain the aircraft payload-range capability, which is a requirement for sub­stantiation. Section 13.1 explains why only results of the integrated climb per­formances in graphical form are given as shown in Figures 13.12 and 13.13. Section 13.4.3 describes the theory for deriving the climb equations. Instructors may assist with the computational work to obtain similar performance graphs for the coursework projects. Readers redoing the graphs as given here may have minor differences in their results, which is understandable.

It is convenient to establish first the climb velocity schedule (Figure 13.12a) and the point performances of the rate of climb (Figure 13.12b) up to the ceiling altitudes and for at least three weights for interpolation. A Bizjet carries out the quasi-steady – state climb at a constant VEAs = 250 knots until it reaches Mach 0.7; thereafter, it continues at a constant Mach number until it reaches the ceiling (i. e., rate of climb = 100 ft/min).

(a) Climb Speed Schedule Figure 13.12. Climb point performances

The next step is to perform the computations for the integrated climb perfor­mance in increments of approximately 5,000-ft altitudes (as convenient; at higher altitudes, smaller steps are appropriate) in which the variables are kept invari­ant using their mean values (see Figure 13.10). Equations 13.15 through 13.18 are used to compute the integrated performances. Figure 13.13 shows the integrated

performances of fuel consumed, distance covered, and time taken to climb at the desired altitude.