Figure 1-7 The Spoke Scan Pattern

CHAPTER ONE

BASIC INSTRUMENT PROCEDURES

The remainder of the pilot's time should be spent confirming the desired performance

and position by quickly scanning those instruments. Start with a spoke scan pattern

(Figure 1-7).

After setting the desired power with the PCLs and monitoring the attitude on the VGI:

Glance at the airspeed indicator and back to the VGI.

ii.

Glance at the altimeter and back to the VGI.

iii.

Glance at the VSI and back to the VGI.

iv.

Glance at the BDHI and back to the VGI.

Etc.

Figure 1-7 The Spoke Scan Pattern

If any deviations in airspeed, altitude, climb rate, or heading control are detected,

appropriate corrections should be made by changing power setting with the PCLs

and/or attitude on the VGI. It is essential to hold the corrections, determine their

effect through scanning, and then recorrect as necessary. Avoid chasing the

performance instruments.

To develop speed in your scan, it is essential to master a technique called "scan shift".

Scan shift is glancing at an instrument, for example, the airspeed indicator, and

immediately shifting back to the VGI. In the shift back to VGI, interpret the

information given on the airspeed indicator. Do not look at the airspeed indicator,

read it, interpret it (255 knots), and then shift back to the VGI. This would require

too much time to complete the scan pattern and results in slow error detection, large

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