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Chapter-2 Straight and Level and Turns-V20_Sport Pilot Handbook 8/30/2021 5:45 PM Page 26

2-26 Rod Machado’s How to Fly an Airplane Handbook

Technique #1–Using the Inclinometer to Fly Coordinated in a Turn
If you’ve ever made a turn in your car and had your sunglasses fly across the dashboard, you know
how it feels to have centrifugal forces act sideways on your machine. Of course, if you properly enter
or exit a freeway ramp your Lady Gaga mega-bling sunglasses typically stay put because those ramps
are both banked and curved. Banking the ramp and curving it at just the right rate keeps the resultant
forces associated with a turn acting straight down through your car seat. Something very similar hap-
pens when you bank an airplane with your ailerons, but only if you use your rudder to keep the nose
pointed in the direction of the turn arc (the airplane’s banked flight path through the air).
If the airplane’s nose points in the direction of the turn arc, then the turn is coordinated and the
force associated with the turn acts straight down through your seat, perpendicular to the airplane’s
lateral axis. The sunglasses on your instrument panel stay put. Similarly, the moveable ball in the
inclinometer (or the slip-skid trapezoidal figure in your primary flight display) should also stay put
in its center position (Figure 59, positions B, E and H). You can take that to the bank.
Let the nose point to the outside of the turn arc and the airplane slips to the inside of the banked
flight path (Figure 59, positions A, D and G). That means those sunglasses and the ball in the incli-
nometer also slip to the inside of the turn. Let the nose point to the inside of the turn arc and the
airplane skids to the outside of the banked flight path (Figure 59, positions C, F and I). Those sun-
glasses as well as the ball skid to the outside of the turn.

An Easy Way to Understanding Aileron and Rudder Coordination

Fig. 59

Primary Primary Primary
Flight Flight Flight
Display Display Display
G H I

The primary flight display inserts above show how the moveable slip-skid (trapezoid) bar indicates a slipping turn
(position G), a coordinated turn (position H) and a skidding turn (position I). These three indications correspond with the
indications in inclinometers (D, E and F) above.