Flight Plan Completion
Revision: March 13, 2012, at 07:57 PM
At this stage of your flight planning, you will have completed your initial flight plan- perhaps a day or so ahead, or even more for a significant trip with many legs. You will have completed the following steps- mostly related to things that do not change from day to day (ie all but the weather):
- Initial route plan- identifying the preferred route and major waypoints along your route (Departure, intermediate stops, destination).
- Airfield and airspace check- modifying the preferred route to accommodate airspace restrictions, identifying alternate airfields and significant waypoints to aid with flight planning and monitoring.
- NOTAMs check- information re airfields and airspace that may impact on your plans, and modifying your plans if necessary.
- Plotted the planned route on the charts.
- For each leg of the route, noted the track, distance, altitudes and frequencies, and flight time and fuel burn assuming nil wind.
- MCT and ECT check- to make sure you can complete the flight in daylight.
- Assembled all the necessary documents- navigation charts, landing charts, flight plan.
Now all that is required is to get the latest current and forecast weather, update your calculations for heading, groundspeed, time and fuel burn for each leg taking into account the expected weather conditions enroute.
Gather weather information using official (MetFlight-GA) and unofficial sources (MetVUW, pilot reports, trusted pilots at your waypoints and destination). Together these should give you a reasonable picture of the weather to expect enroute and at your destination.
It is also a good time to do a sanity check-
- Does the expected weather require me to change my plans?
- Incoming fronts?- Am I going to face changing conditions, with wind and rain?
- Wind?- Effects on flight time, turbulence, cahnge of route to remain upwind in high country?
- Cloudbase?- Adequate clearance from terrain?
- Dewpoint?- Very important for early morning flights- the ambient temperature will continue to drop until the sun is well up and warming the ground- caution fog forming.
It can be psychologically difficult to change your plans, particularly following detailed planning and preparation, and perhaps days of excitement as you mentally go through the flight. But it is important that you step back and review the go/nogo decision in a rational manner. Put aside the promises you may have made, the expectations of your passengers and those at your destination. Clear GO and NOGO conditions are relatively easy, but under marginal conditions you may have a bias to go ahead as planned.
It is far better to be on the ground, looking at a clear blue sky and saying you wished you has said 'GO", than fighting through a black sky wishing you has said 'NOGO'.
Updating your flight plan
Using the latest current and forecast winds, update your flightplan. For each leg update following:
- Wind correction angle. Use the method described in the Effect of Wind module to estimate the WCA to keep you on track. This need only be approximate, as you will be flying in pilotage mode with reference to ground, and able to make adjustments to keep on track.
- Groundspeed. Use the method described in the Effect of Wind module to estimate your groundspeed. Do this with some care (particularly making sure you properly ADD a tailwind component or SUBTRACT a headwind component), as these calculations are important for flight time and fuel burn.
- Flight time (ETE). Leg distance divided by groundspeed. Convert to minutes of flight time, as most legs will be less than 1 hour.
- Fuel burn. Flight time times fuel burn. It is also useful to show fuel remaining after each leg so you can easily see fuel reserve and when to plan your refuelling.
Bear in mind is that normal atmospheric turbulence ensures that the wind velocities experienced as flight progresses will vary considerably from those expected or forecast, particularly in the friction layer, so there is not much point in the pilot of a light aircraft flying VFR in Class G trying to be absolutely precise in determining headings and sector times.
Finally, convert all your track bearings to degrees Magnetic. Bearing taken directly off charts are in degrees True, but in the air your compass will indicate Magnetic. Apply the Variation from your charts to these bearings. For New Zealand, variation is East (negative)- subtract it from the True bearing to get Magnetic. East least, West best.