Homework Assignment 14
Review:
Refresh your memory by skimming (the guide to the instructor’s or
student’s choice of numerical integration computer programs.)
Work :
We will use the numerical integration computer program to explore
aircraft flight performance. We will add realistic equations for angle
How high can it fly? (ceiling)
L
T
V
Variables for Aircraft Longitudinal Flight
Definition of Key Terms
=
=
=
=
T
g
V
h
altitude
speed
acceleration of gravity
thrust
Additional definitions of
terms in text and in
Equations to program
Vh
=
sin
Basic differential equations to be integrated:
Basic equation for “autopilot” :
Comments on Equation for Angle of Attack
(Autopilot)
The model ignores “short period” dynamics. The pilot or autopilot
The autopilot is designed to enable smooth transitions from one
flight path angle to another while realistically limiting g’s
experienced by the pilot.
Graph 1: Air temperature vs altitude
Coordinates:
(altitude (k ft), TA (deg R))
Equations to program (2)
Equations to program (3)
Graph 2: Air density reference
altitude vs altitude
)(/
0
hHh
aa e−
=
)(hH
Equations to program (4)
1
Equations in text and in
Supplement to Class 14B
Notes
Homework Assignment 14:
Run Objectives and Initial Conditions
Run 1: Test the program. Same trajectory as previously, in Phase 1. Start at
with desired flight path angle . Compare with Phase 1 results.
Run 4: Determine max speed with afterburner. Start at kft with .
0=h
25.0=
D
35=h
0=
D
*Helpful Hints on User-Defined Functions
For functions requiring “if then else” logic, taking the desired flight path
angle function as an example, write
If t < t1 then
…
If t < tn then
return y
the instructor to replace with hints
for his or her computing
environment
*Helpful Hints on User-Defined Functions (2)
Ensure that the number of “If” statements equals the number of
“endif” statements.
*These are for ODE Architect for
Homework Assignment 14
Required Output:
Specified in text and in Supplement to Class 14B Notes
Due: