Preparatory Ground Instructor for Navigation Diversions


The definition should include reference to the fact that diversions are improvised navigation.  This should be contrasted with normal navigation preparation undertaken pre-flight.


The aim should include reference to the learning an organized system for managing diversion procedures.


With respect to motivation, attention should be raised concerning the fact that diversions can be required anytime, anyplace.  Pilots, therefore, should have as part of their skill-set the ability to efficiently and safely conduct a navigation diversion. 

Improvised navigation has inherent risks, and these should be reviewed.  There are a variety of reasons related to why diversions are conducted, ranging from changes in plans for a sightseeing flight, to changing flight conditions that present critical conditions for the pilot requiring immediate diversion to an alternate destination. 

Review then with your student the hazards of improvised navigation, including the possibility of critical fuel situations, the possibility of having to navigate through unfamiliar terrain at low level and in poor visibility conditions, and they are typically conducted in an atmosphere for urgency whereby systematic management of the situation is crucial.  During this motivation session, avoid discussion of diversons conducted for mundane reasons for diversion; instead, focus on diversions required for critical flight situations where a disciplined and methodical response from the pilot is required. 

Background Knowledge

By way of background knowledge, review the reasons which might give rise to the need for a diversion.  This should be list that is jointly produced through discussions with your student, applying as much developmental teaching here as possible.  This is where you should include mundane and dramatic reasons for diversion.


The how section should focus on producing a systematic list of procedures on the whiteboard, and it should begin with an effective scenario that has sufficient detail and intensity so as to engage your student’s imagination and of course stimulate critical thinking.  The detail should specify features associated with the rapidly changing weather environment, including specification of visibility and cloud height—conditions that are prerequisite for critical diversions.  Be sure to include a constructive fuel supply.

While developing this scenario, there are also additional considerations you want to keep in mind.  Firstly, you should avoid a scenario location that presents the opportunities of tracking geographic features.  These, of course, are considered to the diversion “gifts”, but they fail to provide opportunity for application of the more complex diversion management tactics necessary in more critical circumstances—i.e., where headings must be estimated, and where progress along the track requires more complex en route strategies.  Secondly, you should devise a scenario that can be flown by your student as the first exercise in the subsequent training flight.  Because of the geographic design of the Vancouver area, with all its airspace confinement, zipping up and down the Fraser River is a common feature of flight training here, and I suggest that your planned diversion exercise for the PGI avoids this.  In this regard, perhaps the best suggestion is to provide a scenario that departs southbound from the vicinity of Langley airport, roughly parallel to the US coastline south of Blaine; this is open country that can be safely flown at a relatively low altitude, and your student will likely have little familiarity with the geographic layout.  A second diversion can then be flown back towards the Canadian border.  Remember that the security procedures for border crossing must be strictly adhered to if this is the plan of action, and be sure not to fly through in the effluent from the US refineries located down there (or at least hold your breath!).

For this how section, you should work through your student and the students map—don’t you do the work for them.  Begin by demonstrating to the student how to properly deploy the map in the confined space of the pilot seat—avoid simply spreading out the map on the table.  Show the student where he is at the time of the scenario—presumably somewhere in the vicinity of Langley Airport—and specify the destination to which the diversion must be conducted.  Once the scenario has been painted, simply begin with the question “What is the first thing we should do, Frankie?”  The discussions should progress naturally from there.  Be sure you keep organized in your board work here, listing out important features of the sequence under organized headings.  With respect to board work, it is also a good idea to simultaneously sketch a facsimile of the students map work on the board, so you can informally elaborate or demonstrate on map-markings procedures.  Avoid reference to distance, and emphasize working directly with time.  Show the strategies you learned as a student, such as using the three or six minute thumb (VTA or VNC Chart), etc.  If you are to use an anatomical feature to estimate time—whether it be fingers or thumb—be sure you review with your student the means by which the time estimate is established, including having the student measure the distance of the fingers or thumb, and having the student using the E6B to calculate average flight times along that distance.

In the spirit of preparing your student for urgent diversions, including low ceiling and poor visibility, teach your student that critical assessment of the proposed track line must be assessed prior to crossing—or departing from—the set heading point.  The idea being, of course, that a student caught in unfamiliar terrain, and in conditions of poor visibility and low ceilings, should be focused on position identification, with their attention focused outside the aircraft, monitoring the changing flight and terrain situation.  Beyond the set heading point, there should be few distractions that would require potentially dangerous heads-down activity in the cockpit, such as line drawing, time calculations, fuel assessment, and radio communications.  During a critical diversion, position certainty is critical and beyond the set heading point, position determination is key, laying out a series of position dots on the map as the flight progresses.

This raises the question as to how to coach your student in handling the airplane during the preparation work that occurs before crossing the set heading point.  Circling is dangerous and should be avoided.  The student should become adept at hands-free flying, requiring effective pitch trim and rudder work to stabilize the aircraft while map preparation and planning is done.  Perhaps the safest advice is to encourage your student to locate and use a geographic straight-line feature that can be tracked away from the current known position and back again, whereby the straight and level tracks being flown along the geographic feature, lasting perhaps 3 to 4 minutes, could be used to focus on map preparation.

I will not provide a lot of detail related to what should be included in the map preparation procedures, as these are available in various publications.  It is important, however, for you to refer during your preparation of the “to do” list that you consult the requirements in the applicable Flight Test Guide, as these should be included in your sequence training. 

Another good practice is to discuss at the end of the how section the strategies that could be used in response to varied requirements for a diversion.  These would include, for example, medical emergencies over familiar terrain—a situation where, clearly, delaying the crossing of the set heading point for the purpose of preparation would be quite meaningless given the circumstances.  The idea here is that the student should be encouraged to pick and choose from the critical diversion sequence more moderate and appropriate tasks that are more suited to the situation.  As is always is the case in responding to changing flight circumstances, flexibility is the key. 

A final yet related point of discussion with your student should revolve from around the use of geographic features as a means of providing track reference during diversions—the so-called diversion gifts.  This is, of course, the Fraser River scenario, and the use of geographic features similar in nature.  In fact, students should always look for geographic gifts when diverting.


The critical risks in conducting this training flight relate to low flying, which is combined—especially with diversions—with relatively high cockpit workload.  Reference here should be made to effective and discipline crosschecking, conducted at regular short intervals, whereby the student’s division of labor is balanced with respect to heads-up and heads-down cockpit activity.  You should also review with your student the legal requirements related to low flying, and you should also discuss the procedures that you require when a diversion requires penetration of a control zone in the Vancouver area.