- From the last positive pinpoint…
- Check heading - DI and compass, variation, drift…
- Check time
- Estimate probable area that you cold be in (10% either way from most probable position)
- Look for a unique feature and map read from ground to map
- When the feature is identified, decide to continue on, return home or divert
- If you cannot establish your position, tell someone! It may be possible to obtain a radar heading or home onto a NDB/VOR.
- Remember - the coast is never far away.
- If all else fails, execute a precautionary landing int he most suitable area. Remember to allow sufficient fuel for the selection and inspection of the landing area.
Expanded Lost Procedure
The basic rule for self correcting a lost situation is to follow the adage to Aviate, Navigate and Communicate. You must continue to fly the aircraft and maintain basic control. Then work through the following steps to re-orientate yourself and regain situational awareness if possible. If this does not work you should attempt to establish communications with an Air Traffic Control unit or other aircraft.
Ideally you will have a positive fix and time noted at your last significant waypoint, which at worst may be the point of origin of your flight. If this was some time ago it will give you a greater radius of uncertainty in which you may be located. This radius is based on the time and groundspeed since your last known fix. With a bigger radius you will need to be aware of a larger range of possible locations and features that you will need to compare to the map you are using.
Where possible use the largest scale chart (1:500,000 is good) available in order to find the greatest number of distinct features. Larger scale charts also tend to be topographically similar to what you see from the window of an aircraft.
When you discover you are lost:
1. Note current time and DI heading. Maintain your current heading (if terrain and visibility, etc. permit) or remain in one location by flying race track or figure-8 orbits (repetitive orbits in the same direction may induce disorientation). Remaining in one location may prevent an airspace infringement or be safer than continued flight (i.e. into an unknown valley).
2. Complete SADIE (or preferred in-flight check) check (on original heading), note if compass and DI are misaligned and if so, note correction. This may give you an indication of how far and which way you are off track. I.e. if you were heading 180° and found you were actually flying 160°, then you are likely to be left of track and may be able to reduce your chart search area accordingly.
If you have reasonable time estimates you may also calculate the likely distance you have covered since you last fix. If you do this add 10% to allow for errors in time, position, wind and the distance covered while calculating these factors.
As part of the SADIE check also note your fuel state and safe endurance time. This action may dictate how long you spend on each step and prioritise your actions.
Experienced pilots say that if you are short of one or more of the following you may consider yourself in trouble:
To this list you may also add Weather/Visibility.
3. Map read- identify unique features around you and locate them on the map. If you only have a single feature you may fly to it as a starting point but your assumed location should be treated with caution until other features can be identified. I.e. Railway or power lines are good features but are not individually identifiable. You may need to follow these until they cross other lines, roads or a town.
Be aware of local or seasonal variations such as the type of power lines depicted, i.e. in the North Island of NZ power lines are generally metal pylons with multiple wires, but in large parts of the South Island they are a single pole with a cross bar and two wires. Rivers or brooks depicted on charts may not contain water depending on the season and recent rainfall, and over winter snow may disguise features.
4. When you have a reasonable idea of your location attempt to identify further distinct features to confirm your identification such as bridges, crossroads or other geographical features.
5. If you are clear of terrain in New Zealand an East/West heading will take you to a coast. Note however that many mountain ranges do not run North/South as many assume but often East/West or similar. Ensure you use your compass and DI to confirm which way you are going and which coast you are arriving on, more than one person has arrived on a coast that was the opposite side of the country than what they thought.
6. If you are still unable to pinpoint your location try to establish communications with an ATC unit or other aircraft. You may have to climb in order to get good reception and fly into radar coverage.
At this point if you have not established your position or have other priorities such as low fuel, low visibility, reducing daylight etc, then you should elect to upgrade you communications to an emergency situation with a PAN or MAYDAY call, squawk 7700 on your transponder and manually activate your locator beacon to declare your distress situation.
7. Following the declaration of an emergency and assuming no further assistance or communication has occurred or is expected then the next option will be a precautionary landing. Return to AVIATING- find the best possible location and plan your next actions. Remain in control of the aircraft and make use of available fuel and daylight- don’t push beyond your own endurance and ability or that of the aircraft.