Air Craft Instruments

BASIC INSTRUMENT PROCEDURES

CHAPTER ONE

Required periodic physiology training exposes the SNFO to the numerous spatial orientation

influences essential in flight. A complete review of the sensations of instrument flight may also

be found in the NATOPS Instrument Flight Manual.

Effective use of flight instruments to supplant the senses must be preceded by knowledge and

confidence. Secondly, interpretation of the combined reports of various instruments is

necessary. Attention must not be fixed on one instrument. The pilot must learn to scan the panel

and gain an almost instantaneous picture of the situation. An NFO must also learn to develop an

efficient scan pattern providing the pilot with descriptive information and when required, switch

to directive communication should the pilot become disoriented to the point of degraded

performance.

Next, it must be recognized that instrument perception is slower than sensory perception. Tests

show a visual interpretation of the actual horizon is one-fifth of a second faster than an

interpretation using instruments. Recovery from a dive takes one and one-half seconds longer on

instruments.

Finally, one must remember that in instrument flight, factors such as fatigue, boredom, and

instrument fixation are more likely to occur. To counteract this, the crewmember may

occasionally move about in the seat, shake their head, or change the cockpit lighting.

102. AIRCRAFT INSTRUMENTS

Aircraft instruments are divided into three categories according to their specific function:

attitude/control instruments, performance instruments, and position instruments.

This chapter describes the basic instruments in each category and their functions. For more

information concerning specific instruments, consult the T-2C NATOPS Flight Manual.

Specifications on the power and operation of each instrument are covered in NATOPS Chapter

Two.

Attitude/Control Instruments. Attitude/control instruments display the attitude of the aircraft

relative to an artificial horizon.

Vertical Gyro Indicator (VGI). The primary flight instrument in the T-2C is the VGI. It

provides the crew with a substitute horizon as a reference in instrument flight. The instrument

shows a horizontal bar, representing the horizon, upon which a miniature aircraft is

superimposed. There are graduated scales on the instrument face to indicate angles of bank and

pitch. Because of precession and the self-leveling feature of the VGI, it is only approximately

accurate, and the pilot must constantly refer to performance instruments in order to perform

precise instrument flight. Whenever a deviation from the desired performance is indicated on

one of the performance instruments, the correction should be made referencing the VGI.

Standby VGI. A standby VGI is located in each cockpit. It is used as an alternate attitude

indicator in the event the primary VGI fails, and as a crosscheck attitude instrument. The

standby VGI will work without AC power; however, it is not guaranteed to function for more

BASIC INSTRUMENT PROCEDURES 1-5