Isolated Aerodrome Procedure (PNR)
Isolated Aerodrome Procedure (PNR) Planning is used when the destination is a long way from any suitable destination alternate airport. The PNR Planning procedure in PPS calculates a PNR that allows for a deviation away from the planned route towards an alternate airport.
This alternate airport can be the departure airport, another airport partway along the planned route or another alternate away from the planned route.
PPS can allow for an isolated aerodrome fuel allowance. This is 2 hours of final reserve fuel based upon cruise configuration at the TOD and also an extra 5 mins that would allow for a turn through 180 degrees to a reciprocal track, in the worst case, to begin routing back to an alternate behind the aircraft when at the PNR.
PPS will calculate the required fuel and the location of the PNR that is the Point of No Return to continue towards the destination or turn towards the alternate.
Remember to activate the Isolated Aerodrome Procedure function in the Settings Manager / PPS X Options User.
If PNR has been selected as visible in the Corporate Data settings the icon will show as per the image above. The setting should appear as the image below, indicating that Isolated Aerodrome PNR has been made visible.
Planning PNR
To demonstrate the PNR planning process the example below shows a flight from LLBG (Tel Aviv) to FSIA (Seychelles) which is a very remote airport. Do not enter any alternate airport yet.
After a valid route for the above has been selected as shown below, the user can enter PNR Planning.
Upon clicking the Isolated Aerodrome icon a PNR Planning tab becomes active as shown below.
The user should enter a suitable enroute alternate airport. The default drop-down menu list of airports is just listed alphabetically so the user will need some prior knowledge of an alternative.
The weather and NOTAMS are available as usual for airport selections. In the example below SCSE is used as it is the closest airport to the destination. It is possible however, that the user can choose the departure airport to be the enroute alternative if nothing closer to the destination is available.
After the calculation is completed, a PNR Point is drawn onto the map as indicated and the Latitude and Longitude of the PNR is shown.
Fuel
The fuel calculation includes the additional 5 mins added on to allow the time to turn to the enroute alternate, which in this case would be almost a 180 degree turn to FMNN.
The user will also notice that the Fuel window represents the 2 hour Final Reserve now being used as the isolated aerodrome tick box has been enabled, see image to the left.
PNR on Flightlog
The PNR Point is also shown on the Flight Log.
PNR and Fast Routing
If Edit Route is selected then the user has the option to open the route in FastRouting to continue editing the route. This is if you wish PPS to make a route rather than a DCT.
If the route is changed at any time then the PNR Point will need to be recalculated. PPS presents the following warning to alert the user.
