Flight Instruments

VERTICAL SPEED INDICATOR

Indicates airplane rate of climb or descent.

(1) Vertical Speed Scale

  • Indicates vertical speed in feet per minuate x 1000.

  • Scale is 0 to 6000 fpm.

(2) Vertical Speed Pointer

  • An accelerometer is incorporated to provide instantaneous reading.

  • Positioned by vertical accelerometer and rate of static pressure change.

PNEUMATIC ALTIMETER

Indicates airplane altitude above reference pressure.

(1) Altitude Window

  • Indicates vertical speed in feet per minuate x 1000.

  • Scale is 0 to 6000 fpm.

(2) Millibars Window

  • Displays barometric setting in millibars as manually set with the BARO set knob

(3) Inches Of Mercury Window

  • Displays barometric setting in inches of mercury as manually set with the BARO set knob

(4) Barometric Set Knob

  • An accelerometer is incorporated to provide instantaneous reading.

  • Positioned by vertical accelerometer and rate of static pressure change.

(5) 100-Foot Pointer

  • Indicates feet on radial dial. Each mark is 20 ft, each digit is 100 ft.

(6) Inner Altitude Bug

  • Manually positioned by altitude bug set knob.

PNEUMATIC AIRSPEED INDICATOR

Indicates airplane airspeed in knots and mach.

(1) Indicated Airspeed Pointer

  • Pointer indicates 0-200 KIAS on outer scale; 200-400 KIAS on inner scale.

  • Pointer indicates Mach on window scale.

(2) Inner Airspeed bug

  • Reference speed for autothrottle.

  • Manually positioned by (4).

(3) Airspeed Bugs

  • Three manually positioned reference bugs (on outer ring).

(4) Airspeed Bug Set Knob

  • Turned to position inner airspeed bug.

(5) Max Operating Speed Pointer

  • Indicates the max operating speed (Vmo) for existing altitude.

SAT/TAS INDICATOR

Indicates airplane standard air temperature and true airspeed

(1) Static Air Temperature Indicator

  • Indicates static air temperature.

(2) True Airspeed Indicator

  • Indicates true airspeed.

RADIO MAGNETIC INDICATOR

Combines a magnetic compass with navigation signals from VORs and NDBs to provide bearing information to the selected station.

(1) No. 1 VOR/ADF Selector

  • When turned to the left (vertical), selects No. 1 VOR information to the No. 1 VOR/ADF Pointer.

  • When turned to the right (horizontal), selects No. 1 ADF information to the No. 1 VOR/ADF pointer.

(2) No. 2 VOR/ADF Selector

  • When turned to the left (vertical), selects No. 2 VOR information to the No. 2 VOR/ADF Pointer.

  • When turned to the right (horizontal), selects No. 2 ADF information to the No. 2 VOR/ADF pointer.

(3) No. 1 & 2 VOR/ADF pointer

  • Points towards the selected station based on the given source from (1) & (2).

HORIZONTAL SITUATION INDICATOR

Integrates the directional gyro, course deviation indicator, and glide slope to provide comprehensive display of flight path relative to a chosen navigation source.

(1) Miles Window

  • Displays associated DME distance.

(2) Course Window

  • Displays course selected by pilot.

(3) Glideslope Scale & Deviation Pointer

  • In conjunction with deviation pointer indicates vertical deviation above or below the glideslope.

  • Each mark indicates 1/4-degree.

  • Vertical deviation pointer out of view with VOR selected.

(4) To-From Indicator

  • Points toward a line through the VOR station perpendicular to the seleccted course.

(5) Heading Bug

  • Indicates heading selected by pilot.

(6) Course Deviation Bar & Scale

  • As a reference on the course deviation scale, indicates deviation from the selected course.

  • Each dot equals 5-degrees on VOR and 1 1/4-degrees on LOC.

(7) Heading Control

  • Rotated to set heading bug.

(8) Course Control

  • Rotated to set course indicator.

ATTITUDE DIRECTION INDICATOR

Provides information about the orientation of the aircraft relative to the horizon.

(1) Go-Around Light

  • Illuminates to indicate flight director go-around mode.

(2) Bank Angle Scale

  • Displays roll attitude as indicated by roll index (4).

(3) Max Bank Angle

  • Displays the maximum allowed bank angle.

(4) Roll Index

  • Indicates roll attitude on bank angle scale (2).

(5) Pitch Scale

  • Displays pitch attitude in reference to airplane symbol.

(6) Fast-Slow Indicator

  • Indicates airpseed deviation fast (F) or slow (S).

  • References to the captain's inner airspeed bug.

(7) Glideslope Deviation Scale & Pointer

  • Indicates deviation from center of glideslope beam.

(8) Expanded Localizer Indicator

  • Lateral movement from center line indicates displacement from localizer.

(9) Test Switch

  • Push-to-test switch checks the indicator's amplifiers and servos.

(10) Slip Indicator

  • Skid ball indicates amount of yaw.

INSTRUMENT COMPARATOR

Compares data outputs of flight instruments and displays an appropriate warning when the captain's and first officer's instruments disagree.

(1) Monitor Power Light

  • Illuminates at loss of electrical power to the comparator.

(2) Heading Light

  • Indicates a heading difference of 6 degrees between HSIs.

(3) Horizon Pitch Light

  • Indicates a difference of 4 to 6 degrees in pitch between ADIs.

(4) Roll Pitch Light

  • Indicates a difference of 4 to 6 degrees in roll between ADIs.

(5) Glideslope Light

  • Both nav receivers mus be tuned to an active localizer freuqnecy; GS flags not in view.

  • On at 3/4 to 1-dot difference on HSIs.

(6) Localizer Light

  • Indicates heading selected by pilot.

(7) Radio Altimeter Light

  • Indicates a difference between RAs of

    • 55 ft at 1500 ft

    • 25 ft at 200 ft

    • 5 ft at touchdown.

RADIO ALTIMETER INDICATOR

Provides a visual display of airplane terrain clearance, from 0 to 2500 ft. A light will warn the crew that the airplane is at or below the selected altitude.

(1) Altitude Pointer

  • Indicates height above ground level (AGL).

(2) Bug & Control

  • Rotated to position bug to selected height

(3) Test Switch

  • Drives altitude pointer to 40 ft and DH light will illuminate.

(4) DH Light

  • Illuminated if airplane is at or below selected height.

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