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It is important to bear in mind that the objective of the pilot navigation cross-country exercise is to practise navigation by maintaining accurate headings, calculating and making corrections for drift, and calculating accurate ETA. Accurate map reading for exact determination of aircraft position is essential to provide the necessary information for calculation of heading and ETA corrections when required.
En route
Provided the set-heading procedure is properly completed, you can then concentrate on accurate flying, identifying checkpoints, and maintaining a good lookout. A prior knowledge  of ETA over checkpoints along the route will allow you to anticipate and thereby identify them easily as the flight progresses. However, look out for other traffic must not be sacrificed to the navigation of the helicopter. Also perform normal in-flight checks at the prescribed intervals.
ETA Revisions
At the first positive pinpoint, ideally between 10 and 25 miles from the departure point, the ground speed should be calculated and ETA revised if necessary. Rely on the navigation instruments in the aircraft, rather than inexperienced personal judgement. It is most important to maintain a steady planned heading and airspeed. If you cannot at once recognize the track being made, do not suspect the compass of unreliable behaviour; continue to hold a steady heading until you reach a recognizable checkpoint. If a heading indicator is being used, check its heading frequently with the magnetic compass and reset it as necessary.
Checkpoints and Pinpoints
Time is one of the essentials of navigation, so acquire the habit of calculating ETA for en route checkpoints. This will help locate checkpoints by preventing the habit of looking for specific places on the ground too soon or too late. It is imperative that a reliable watch or clock be  on board the helicopter during cross-country flights. The number of pinpoints on a leg varies according to the length of the leg. Usually one pinpoint every 10 minutes is sufficient, but more may be used if necessary. Once the aircraft has passed the pinpoint, immediately begin to anticipate the next checkpoint in the same manner as the previous one was anticipated.
Do not fly a zigzag path from check-point to check-point when the checkpoints can be readily identified from a position on or near the required track. There is no disgrace in not arriving directly over a check or turning point. Alteration in heading should be deliberate and aimed  at flying in as straight a line as possible.
DIVERTING TO AN ALTERNATE DESTINATION
One of the skills required of the helicopter pilot is the ability to rapidly estimate a new heading to an alternate destination when, for various reasons, continuation of the flight is impracticable. Computation of headings, speeds, distances, and ETA in flight involves the same basic procedures as those used in pre-flight planning. However, because of space and time limitations and having to fly the helicopter simultaneously with computations, the pilot must take advantage of all possible short cuts. It is rarely practical to actually plot a line on a chart and mark checkpoints and distances as in pre-flight planning.
With a little practice, headings to alternates can be determined quickly with reasonable accuracy, by interpolation and mental transposition of airways and air routes on the chart  or the azimuth information on the compass rose encircling VOR stations. These all have the advantage of already containing the magnetic variation for the general area. Use a pencil or the hand (on edge) as a straight edge. If airways or a compass rose are not close enough on the chart to be used, an angle may be estimated as being a fraction of the 90-degree angle between the meridians of longitude and parallels of latitude found on the chart. If possible, draw a line freehand on the chart from the divert point to the alternate destination.
Distances can be estimated accurately enough for diversion purposes by using the thumb  and index finger as “dividers” applied against the scale on the chart, or easier still, against the mileage lines that were marked along the original track before the flight began. The compass rose circles around VOR stations are all 35 statute (30 nautical) miles approximately in diameter on Canadian 1:500,000 aeronautical charts.
　
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