FLIGHT DIVERSION
There will probably come a time in your flight career when you will not be able to make it to your destination. This can be the result of unpredictable weather conditions, a system malfunction, or poor preflight planning. In any case, you will need to be able to safely and efficiently divert to an alternate destination. Before any cross-country flight, check the charts for airports or suitable landing areas along or near your route of flight. Also, check for navaids that can be used during a diversion.
Computing course, time, speed, and distance information in flight requires the same computations used during preflight planning. However, because of the limited cockpit space, and because you must divide your attention between flying the helicopter, making calculations, and scanning for other aircraft, you should take advantage of all possible shortcuts and rule-ofthumb computations.
When in flight, it is rarely practical to actually plot a course on a sectional chart and mark checkpoints and distances. Furthermore, because an alternate airport is usually not very far from your original course, actual plotting is seldom necessary.
A course to an alternate can be measured accurately with a protractor or plotter, but can also be measured with reasonable accuracy using a straightedge and the compass rose depicted around VOR stations. This approximation can be made on the basis of a radial from a nearby VOR or an airway that closely parallels the course to your alternate. However, you must remember that the magnetic heading associated with a VOR radial or printed airway is outbound from the station. To find the course TO the station, it may be necessary to determine the reciprocal of the indicated heading.