Objective:

To develop the students understanding of air navigation and proper usage of navigational equipment.

Elements:

Pilotage - Navigation by visual reference to landmarks.
* Note - When flying by pilotage, match as much as possible of what you see on the ground to the features on your chart to avoid getting lost.
  • Sectional (6 months)
  • WAC (12 months)
  • TAC (6 months)
  • A/FD (56 days)
Dead Reckoning - Based on time, speed, and distance calculations.
  • Plot course using navigation plotter (true course)
  • Measure distance between two points
  • Collect weather data (winds, temp, etc...)
  • Calculate TAS and fuel consumption from POH
  • Use winds aloft and E6B to calculate wind correction angle and ground speed
  • Convert True heading to Mag heading according to Variation.
Radio Navigation - Navigation by reference to VOR, ADF, and GPS.
  1. VOR - Very high frequency Omnidirectional Range
    • Provides course guidence TO and From the station
    • VOR/DME and VORTAC signal provides slant range distance info
    • 108.0 MHz to 117.95 MHz
    • Limited to line of sight
    • Terminal - 12,000' and below = 25 mile radius
    • Low - 18,000' and below = 40 mile radius
    • High -
      below 14,500' = 40 mile radius
      14,500' to 18,000' = 100 mile radius
      18,000' to FL 450 = 130 mile radius
      FL 450 to 60,000' = 100 mile radius

  2. ADF - Automatic Direction Finder (indicator in airplane)
    NDB - Non-Directional Radio Beacons (ground equipment)
    • ADF receives the signal from NDB which transmits in all directions
    • Homing vs. Tracking (wind correction)
    • Not limited to line of sight
    • Transmits low and medium frequency range (190 kHz to 535 kHz)
    • LOM - Compass Locator - 15 miles (co-located with ILS)
    • MH - Medium High - 25 miles
    • H - High - 50 miles
    • HH - High High - 75 miles

  3. LORAN - Long Range Navigation. This system operates from chains of transmitters broadcasting signals in the frequence (LF) spectrum.

  4. GPS - Global Positioning System
    • Space-based radio navigation using satellites providing global coverage.
    • 26 satellites orbiting approximately 10,900 NM above the earth.
    • Extremely accurate - Used in the IFR environment for approaches.
    • Transmitted through UHF frequence range
    • Virtually unaffected by weather however subject to line-of-sight limitations

Common Errors:

  1. Failure to identify ground features using a VFR sectional or WAC.
  2. Not compensating for wind drift.
  3. Failing to convert True heading to Mag heading.
  4. Allowing the DG to presess without cross checking it with mag compus.
  5. Not understanding general direction i.e. 360° is north.
  6. Improper tune and identification.
  7. VOR Reverse sensing.
  8. Getting lost and using improper procedures

References:

  • Aeronautical Information Manual (AIM) - Chapter 1
  • Pilot's Handbook of Aeronautical Knowledge, pp 14-18 through 14-26

Notes:

Situational awarness is the key

Variation is the difference between True and Mag. north
EAST IS LEAST WEST IS BEST
Deviation magnetic fields in the aircraft that disturb the compass
True Course (TC) = Plot from sectional
True Heading (TH) = Apply wind correction
Mag. Course (MC) = Add/Subtract variation
Mag. Heading (MH) = Apply deviation

VOR transmits radials FROM the station (360°) through the use of 2 signals.
  • Reference - signal sends out a constant pulse around the VOR
  • Phase - signal is electronically rotated at 1800 RPM
The VOR receiver in the plane measures the phase difference between the two signals and calculates the direction from the station.

ADF/NDB
MH+RB=MB to the station
LIMITATIONS:
  Night effect signals refracted by the ionosphere and return to earth fluctuates ADF needle.
  Thunderstorm effect points in the direction of lightening (Poorman's strike finder)

P roper
P lanning
P revents
P oor
P erformance