Navigation
Objectives
- To teach you to prepare for and be able to conduct safe cross-country flights.
Why?
- It’s time to go somewhere!
Link
- Take-off and landing.
- Range and endurance.
- Straight and Level flight.
Review questions
- When reducing power in level flight, what control movement will be necessary to maintain straight and level flight ?
- What Attitude + Power = Performance means?
- Why is trimming the aircraft important?
Document on board.
- Certificate of Airworthiness.
- Certificate of Registration.
- Radio Station Licence (for the aircraft).
- Pilot Operating Handbook (P.O.H)
- Weight and Balance.
- Interceptor Order.
- Crew Licences.
- Proof of Insurance.
- Journey log book.
Chart
VNC (Canada)/ Sectional Aeronautical Charts (USA):
- Lambert conformal conic projection.
- scale is 1:500,000
- Straight line = great circle.
- The standard chart.
VTA (Canada)/ TCA (USA) :
- Visual Terminal Area chart.
- Transverse Mercator projection
- scale is 1:250,000
- Straight line = rhumb line
- To satisfy special operational requirement at certain high density traffic airports having complex airspace structure.
Weather
- METAR
- TAF
- FD
- GFA
- NOTAM
- ATIS
- VISUAL.
Weather minima for VFR aircraft
- Uncontrolled Airspace.
- Controlled Zone.
- Other controlled airspace.
- SVFR.
- Night.
- VFR Over-the-Top:
- VFR-OTT qualified
- Day only.
- Operated at least 1000’ vertical distance from cloud.
- Visibility must be at least five miles.
- When operating between two layers, those layers must be at least 5000’ apart.
Weight and Balance
- An airplane must only be flown within certificated limits of weight and balance to ensure that it remains controllable, performs adequately and is not overstressed.
- Correct weight and balance means:
- Maximum allowable weight is not exceeded
- Center of gravity (CG) is within a specified range.
- Calculate
- Take-off and landing weights
- Make sure aircraft is within C of G limits.
Aft Center of Gravity
- More efficient but decreases stability.
- Less than usual back pressure on take off and landing.
- Chance of tail strike on landing.
- Lower stall speed but stall characteristic can be dangerous. (recovery may even be impossible because the pilot is running out of elevator control).
- Tail may drop instead of the nose.
Forward Center of Gravity
- Decreases performance.
- Apply more than usual back pressure at rotation.
- Apply more than usual back pressure for landing and makes flaring for landing more difficult.
- Chance of wheelbarrowing or even pop strike.
- Higher stall speed.
- The nose will tend to drop more than usual at stall.
Performance: calculate take off distance
- Determine the weight of aircraft for take-off
- Determine the pressure altitude for the aerodrome (METAR/TAF).
- Determine the temperature at the aerodrome (METAR/TAF).
- Determine the wind component (METAR/TAF, RUNWAY, CROWWIND GRAPH)
Performance: calculate Time, fuel and distance to climb
- Determine pressure altitude on the ground.
- Determine pressure altitude for the cruise altitude.
- You may need to interpolate between the number if your pressure altitudes are not even 1000’s feet.
Calculate cruise performance
- With :
- Pressure altitude.
- Temprature.
- Power (RPM).
- refer to POH diagram to get
- airspeed
- fuel consumption.
Performance: calculate landing distance
- Determine the weight of aircraft for landing.
- Determine the pressure altitude for the aerodrome (METAR/TAF).
- Determine the temperature at the aerodrome (METAR/TAF).
- Determine the wind component (METAR/TAF, RUNWAY, CROWWIND GRAPH)
Airspeed calibration
- Calculate the TAS by using Performance chart.
- Calculate CAS using the flight computer to correct our TAS for temperature and pressure.
- Calculate IAS by corrected our CAS with airspeed calibration chart.
Definition
- Track = without wind.
- Heading = with wind.
- True track:
- The patch the aircraft follows over the ground relative to the true north (line draw on the map).
- Magnetic track:
- The patch the aircraft follows over the ground relative to the magnetic north.
- True heading:
- The direction of the aircraft is pointing relative to the true north.
- Magnetic heading:
- The direction of the aircraft is pointing relative to the magnetic north. (It’s this heading that you follow during your navigation).
- Variation:
- Degrees difference between true north and true heading.
Navigation preparation: Part1
Select route:
- Find set heading point.
- Make it as straight as possible.
- Note Airspace Restrictions
- Check airport advisory for destination.
- Draw line to SHP.
- Draw line from SHP to Destination/Turn Point.
- Draw 10° drift lines.
- Make mark at the midpoint of each leg.
- Make mark at 10 NM intervals.
- Make mark for each check points.
- Determine MOCA for each leg.
- Determine True Track for each leg.
- Determine average variation for each leg.
- Note alternate airports enroute
- Mark airport frequencies.
Navigation preparation: Part 2
- Check:
- Weather.
- Make GO/NO GO decision.
- Notams.
- Weather.
- Calculate:
- Weight and Balance.
- Determine cruising altitudes.
- Take-off distance, time and fuel distance to climb.
- Crosswind components
- Landing distance.
- Fuel burn + reserve fuel and add 20%.
- Cruise performance : TAS/ CAS/ IAS.
- True heading.
- Magnetic heading.
- Ground speed.
- Departure time.
- ETE – Estimated Time Enroute. (for each leg).
- ETA – Estimated Time for Arrival.
- Complete the flight planning form.
- Flight plan/itinerary complete and file.
Departure procedures
Overhead departure:
- Set heading over the airport
- Advantage:
- If you are unfamiliar with area and there are no obvious landmark near by.
- Disadvantage:
- Use time and fuel to circle over the airport.
- It can be difficult to get clearance for this type of departure within a control zone.
Enroute Climb:
- Take off, climb to a safe altitude and turn to intercept track
- Advantage:
- Most direct way.
- Useful when departing from unfamiliar airports.
- using first check point to confirm track.
- Disadvantage:
- easy to fly past your track.
Set heading point:
- Set heading at a distinct landmark or a familiar point near the airport.
- Advantage:
- Most efficient method to use.
- Allows you to concentrate on departure procedures.
- Disadvantage:
- Can be difficult at unfamiliar airport with no obvious landmarks nearby.
Set Heading Procedure
- Reset and set Heading Indicator.
- Take time over SHP.
- Turn to planned course.
- Track (check departure angle).
- Set Power to cruise trpm and lean mixture.
- Revise ETA.
Enroute procedure
- Hold a constant heading.
- Reset Heading Indicator every 15 minutes.
- Revise ETA with Checkpoints
- Cockpit checks (carb icing, engine gauges…).
- Map oriented to direction of flight.
- Check position (landmark).
- Correct for Wind Drift
- File flight Log entries (time over check points, groundspeed, revised ETA…).
- Obtain Revised Weather Forecasts (FSS)
- Maintain Listening Watch on Appropriate Frequency. weather updates from FSS.
- Lookout for Emergency Landing Areas
Descent and Arrival Procedures
- Descent:
- Cabin check (seats, baggage, etc).
- Mixture rich.
- Start descend at 500 fpm.
- Avoid obstacles.
- Joining the circuit:
- Make radio calls.
- Plan the approach.
- Join the Circuit and Land.
- Close Flight Plan (within 60 minutes through tower or FSS).
Drift correction
Visual Alteration.
Double Track Error.
Opening and Closing Angles.
Visual Alteration
- Establish your position
- Fly to a known feature along the track.
- Once back on track apply necessary correction to maintain track.
Double Track Error
- This method only works before your half way point. Otherwise, by the time you get back on track, you will be past your destination.
- Estimate track error by using your drift line from the Set Heading Point.
- Determine the time flown since departure from the Set Heading Point, it will take about the same time to get back on track.
- Double error to get back to track.
- Once on track subtract half correction to maintain track again.
- Determine your new ground speed and ETA.
Opening and Closing Angles.
- Only if you are past your half way point.
- This method only get you to destination, it will not get you back on track.
- Determine your position with relation to track.
- Determine your opening angle off track.
- The opening angle of track is the angle between your position and your track using your 10° drift line from your point of departure.
- Determine your closing angle off track.
- The closing angle off is the angle between your position and your 10° drift line from your destination.
- Add your opening angle and your closing angle together to determine your drift correction and turn toward the track by this amount.
- Fly the new heading until arrival at destination.
- If you have drifted to the left: add your drift angle.
- If you have drifted to the right: subtract your drift angles from your heading.
Diversions
- There are various reason for one to divert.
- Deteriorating weather on intended route.
- Fuel shortage, possibly due to strong wind.
- Mechanical problems.
Diversion: basic theory
Distance:
- 1 degree fo latitude = 60 nm.
- 1 minute of latitude = 1nautical mile.
- Approximately half thumb = 8nm/VNC and 4nm/VTA. (measure your own thumb).
Time:
- For 90kt average:
- Time = (distance /3) * 2
- Example: (12 nm / 3) * 2 = 8 minute to fly 12 nautical miles.
- Make correction based on wind.
Fuel:
- Fuel = Time * Fuel flow.
Estimate track and heading:
- Determine where you are and where you want to go.
- Draw Line and half way point.
- Use VOR radials on the map or latitude/ longitude line.
- Follow roads, rivers, shorelines etc.
- Compass rose.
- Correct for crosswind.
Altitude:
- Moca
- Weather.
- Circle any obstacles
Radio:
- Inform FSS /FIC:
- New destination
- new ETA.
Diversions procedures
- Slow down.
- Circle where you are and new destination.
- Establish a new track over a check point or a landmark.
- Drawn a line and mark half way point. (mark checkpoint as weel).
Over the check point:
- Set heading Indicator (reset every 15 minutes).
- Cruise rpm.
- Mixture Lean.
- Record time over check point.
- Estimate:
- Distance.
- Time.
- New ETA.
- Fuel.
- Inform FSS/FIC of your new destination and ETA.
- Record time over half way point.
Lost procedure
- Climb to see better and further.
- Note what your last know position was on the map and circle it or do circle of uncertainty.
- Slow the aircraft.
- Maintain heading and look for a know landmark.
- if you find it, you are not longer lost.
- Reach this point and begin the diversion procedure to come back on your track.
- If you are unable to use landmark to determine location:
- Use all available navigation system (VOR, DF steer…).
- Contact ATC or FSS for help (try to locate the closest airport with DF equipment).
- Plan a precautionary landing if low in fuel or unable to maintain VFR conditions.
- PAN PAN call.
Review questions
- How do you determine your true track ?
- What is the difference between true track and true heading ?
- what lost procedure can you perform ?
- What is the diference between geographic north and magnetic north ?
- What are the three type of departure proocedures ?
- What are some factors in determining a suitable point for a diversion?
- What procedure can we follow if we are lost?
