by Jonathan M. Stern
Basic Attitude Instrument Flying
After the fatal crash of a light airplane flown by a husband and wife, it was learned that the couple had a long history of arguments. People speculated that the two had an argument, the wife turned off the ignition, and then threw the key out the window. In the wreckage, no ignition key was found, and the ignition switch was in the off position.
The basic "formula" for flying an airplane is attitude + power = performance. This formula simply states that for any given attitude (pitch and bank) and power setting a certain performance results. If you understand this formula, you can understand what basic attitude instrument flying is all about.
While flying in the clouds or otherwise without visual reference to the horizon or the ground, pilots must constantly be aware of the attitude, power setting, and performance of their airplanes. Because the human sense of balance is not adequate to keep an airplane flying right side up, the pilot must scan the instruments to make this determination.
Although many different scan patterns may work, most instrument flying authorities recommend a scan pattern that includes the attitude indicator between every other instrument. Because attitude + power = performance, once you have set the power, it is imperative to set and maintain the desired attitude. After checking the attitude, other instruments are scanned to determine that the desired performance is resulting. If it is, the attitude indicator is checked to ensure that the attitude is maintained. If the resultant performance is not what is desired, the attitude indicator must be used to control the airplane to correct the attitude.
Three fundamental skills are involved in basic attitude instrument flying:
- Instrument scanning—it is important that you not fixate on any one instrument, omit an instrument that should be included in your scan, or over-emphasize any instrument.
- Instrument interpretation—requires a thorough understanding of the operation and display of each instrument.
- Aircraft control—requires the capability to make control inputs in the correct manner without outside visual references, This ability typically involves substituting the attitude indicator for the out the windscreen view for pitch and bank control.
Power is controlled the same way with or without outside visual references.