Exercise 18 – Navigation

Exercise 18 – Navigation

NAVIGATION: AIR EXERCISE

1. START POINT PROCEDURES

Overhead

  • Establish at planned altitude and cruise IAS
  • Pass overhead on planned heading
  • Start the stopwatch
  • Gross error check – lead-out feature
  • Heading, Airspeed, Altitude, Time ( H.A.A.T.) FIRE checks

Commercial Departure

  • Intercepting planned track ‘known’ start point
  • On intercept – start stopwatch
  • Cruise climb
  • Departure and Heading, Airspeed, Altitude, Time. FIRE checks

2. EN ROUTE

Map Reading

  • Map orientation
  • Fix features: size, uniqueness, contrast – daylight, seasonal variations
  • Work big to small

Fixing

  • Bearing estimation – relative bearing
  • Range estimation – pro rata method

3. EVENT TECHNIQUE

  • Clock to map to ground
  • Refer to map 2 to 3 mins before ETA at fix
  • Take and plot fix
  • Put map away until next event
  • Between events – lookout, fly accurately, cruise/ fuel checks
  • Note: F.R.E.D.A checks
    Fuel. Radio. Equipment. Directional gyro. Altimeter

4. ACTIONS AFTER FIXING

  • Log ATA at/abeam fix
  • Calculate alteration of heading
  • Turn onto new heading
  • Revise and log new ETAs
  • Advise ATC of new ETAs, A/R

5. TURNING POINT PROCEDURE

  • Identify turning point: pre-Heading, Airspeed, Altitude, Time. FIRE checks
  • Overfly it
  • Overhead: zero/start stopwatch, turn onto new heading
  • Gross error check
  • Log ATA
  • Adjust altitude: A/R
  • H.A.A.T. FIRE checks
  • RT: A/R
  • Note: 4 T’s of navigation for VFR flying
    Time. Turn. Talk. Task

6. DIVERSION NAVIGATION

  • Select suitable start point
  • Mark new track on map
  • Measure/estimate new track
  • Calculate new heading
  • At start point – turn to new heading, zero/start stopwatch
  • Calculate ETA, fuel burn, Safety Altitude
  • Log new data
  • Select en route fix point(s)
  • Navigate as normal
  • ATC – advise of intentions

7. LOST PROCEDURE

  • Stick to flight plan
  • Check flying planned heading, speed, time
  • Re-check calculations
  • Not lost until 2 fix points missed
  • Get help early from ATC
  • Use GPS/radio aids to check position
  • Resume route/divert?

NAVIGATION: AMPLIFYING NOTES

GENERAL

  • Stress that navigation is an integral part of flying and not in addition to the pilot’s normal duties. For this reason the techniques used are simple and the navigational activity in the air is kept to a minimum by sound pre-flight planning.
  • Ensure your student understands that navigating successfully depends on accurate knowledge of distance and direction from a known point (start point, fix or turning point). In visual navigation, distance is determined on the basis of timing and speed so flying accurately at the planned IAS is essential, as is maintaining the planned heading. In summary: without accurate flying, navigation will fail.
  • The syllabus ensures that the potentially complex task of navigation is presented to students in a series of lessons of gradually increasing complexity. Never try to short cut this process and, even with a good student, ensure that before the first formal navigation lesson you have introduced your student to the following aspects of navigation during his general flying:
  1. Use of large features for orientation.
  2. Use of the Direction Indicator.
  3. Map orientation.
  4. Simple map reading.
  5. Estimation of distances, bearings and headings to reach a chosen point.

BEFORE FLIGHT

  • Preparatory Instruction
  1. Meteorological forecasts
  2. Map preparation
  3. Estimation and computation of headings, groundspeeds, ETAs and Minimum Safe Altitudes
  4. Pilot Navigation Technique
  5. Aeronautical Information Publications
  6. Air Traffic Regulations
  7. Distress and lost procedures
  8. Diversions
  9. Range and Endurance flying
  • Pre-flight planning

Initially, you should help your student to prepare flight logs and maps and advise him on the choice of fixes. Stress the importance of thorough and meticulous planning and route study before dual and solo exercises. Check his calculations before the early exercises and encourage him to confirm his own computer calculations using Mental Dead Reckoning methods as an independent check. Teach your student to prepare his maps for each exercise in accordance with “The Pilot Visual Navigation Student Training Standardization Supplement” which he will have been issued with.

  • Route Study

Stress the importance of thorough pre-flight route study to minimize the time spent in the air referring to the map. Ensure that he is familiar with the turning points and fix points, and can visualise how they will look from the air. The best way to do this is take his map away and get him to describe the MAJOR features of each leg (e.g. – after departure, town on the left, hills right, after 10 mins, cross major road …..etc.). This not only serves to check that he really has studied the route but also ensures that he is not going into too much detail.

DURING FLIGHT

  • Event Technique

During planning, your student will calculate and note on his map the (elapsed) times of significant events (arrival at fix/turning points; RT frequency changes etc.). The technique is time driven, designed to ensure that the pilot allocates his time sensibly between flying the aeroplane, navigation, checks and maintaining a good lookout. If employed correctly, it eliminates the common error of over map reading. Teach your student to work from clock to map to event and, once an event has been actioned, to note the time of the next event and to put his map away until a couple of minutes before the next one. Then he can look at it – just to refresh his memory – and look for the appropriate feature on the ground. Between events he should concentrate on accurate flying and lookout. Stress that it’s completely unnecessary to know, second by second, exactly where you are – only where you were at the last fix and when and what the next event is. GPS and radio navigation aids should NOT be used initially and, later in the syllabus, be regarded purely as confirmation of position.

MAP READING

1. Teach that the value and reliability of a fix-point depends on its uniqueness, size and contrast in relation to the surrounding area which may change with the angle of observation and with seasonal or weather variations: for example, higher ground is not so readily apparent from high altitude and small rivers may dry up in summer.

2. When looking for fixes and turning points, teach your student to work from large general features to small specific areas and to map read only at pre-planned fixes. Curb any tendency to over-navigate and “track crawl”.

3. Show the value of map orientation along track so that the relative bearings of features on the ground and on the map correspond.

4. Teach how to take a visual fix – that is to translate the view of the ground into a precise mark on the map (never assume this skill is a “given”). The reciprocal of the relative bearing of a feature gives the bearing from the feature which, coupled with the range, gives the aeroplane’s position. There are several ways of estimating range but the most reliable is the “pro rata” method by comparing the range from the aeroplane to the feature with distance that between two landmarks that can also be seen on the ground and whose distance apart can be taken from the map.

  • Start point

a. Overhead Departure.

Teach:

1. Climb to planned altitude and settle at cruise IAS
2. Aim to pass overhead on planned heading for leg
3. Overhead, start the stopwatch
4. Identify a lead-out feature as a gross error check
5. Carry out a H.A.A.T. FIRE check:

Heading Confirm the correct heading from the map and confirm that the aircraft is flying
in the correct direction by reference to a “lead-out feature”.
Airspeed Confirm on speed. Altitude Confirm at the planned altitude.
Time Check that the stop watch is running and note the time of the next event.
Fuel As expected, sufficient, balanced
Instruments DI/Compass, Altimeter
Radio Correct frequency. Next frequency?
Engine Ts & Ps

b. Commercial Departure

Teach intercepting the planned track either by turning onto an intercept heading after take-off and making a visual assessment of when the aircraft is on track or by flying to a unique and significant feature on track before turning onto the planned heading. In either case the stop watch should be started as the aircraft is turned onto the initial intercept heading and a cruise climb carried out from that point. Departure checks should be carried out during the cruise climb and “HAAT” checks once the aircraft is established on track to the first turning point.

FLYING THE ROUTE

  • On the early lessons, fly the aeroplane yourself when teaching elements of the ‘Event Technique’ but let the student fly as much as possible between events. This will help to make the point that “navigating” takes up relatively little time and effort. Stress the basic straight and level technique of Lookout, Attitude, Instruments and how looking well ahead of the aircraft towards a feature helps to
    maintain heading accurately.
  • Teach actions at a fix-point:

1. Monitor the clock and two to three minutes before the fix (or a little earlier if there is a tailwind), pick up the map, look well ahead (about two miles initially) and work from large to small features to identify the fix.
2. When over or abeam the fix, plot it (as detailed in the Students’ Study Guide) and note time on the NAVLOG. Put the map away.
3. WITHOUT DELAY, calculate any alteration of heading required

a. Before the half way point, estimate the track error (using the 10° drawn lines on the map), and turn through twice that angle TOWARDS PLANNED TRACK. Maintain the new heading for the same time as flown from the last fix, then turn back onto the original heading ± an estimated correction for the unexpected drift. This regains the planned track.
b. After half way, estimate the track error and the closing angle to the turning point/destination, add them together and alter heading by that amount. This leads directly to the turning point/destination. Turn onto new heading or, if on track at the fix, maintain heading.

4. Update ETAs for the remaining events on the leg. The simplest method for your student to learn is the proportional one: for example one minute late at a fix half way along a leg means two minutes late at the end – one minute early at the one third point means two minutes early at the two-thirds point and three minutes early at the end. Enter details in the NAVLOG.

After the fix has been actioned, teach your student to note the time for the next event and then concentrate on accurate flying and lookout. Stress the need for regular cruise checks (particularly comparing fuel remaining with that required) and the need to take early action if fuel reserves are compromised.

  •  Turning point procedure

Teach your student that, once the turning point (or the general area in which it lies) has been identified, to turn towards it (if necessary), carry out the pre-turning H.A.A.T checks and overfly it. Overhead, stop and zero the watch, turn onto the new heading, re-start the watch and adjust altitude if required. Log the ATA over the turning point, then carry out the H.A.A.T. FIRE checks. If the turning point is not seen, turn on ETA, remembering to zero and re-start the watch.

DIVERSION NAVIGATION

  • Every diversion should commence from a specific point.

Teach your student:

1. To select a start point sufficiently far from the aircraft’s present position to give time to plan an initial heading and in the general direction of the diversion destination.
2. Whilst flying towards the start point, to mark the new track on his map and estimate or measure the true track and then to calculate and apply drift and variation to obtain a magnetic heading to fly. (If there is insufficient time to calculate a heading before arriving at the start point then to turn onto the magnetic track whilst calculating the heading.)
3. To reset and start the stop watch when passing over the start point.
4. Once established on heading, to calculate an ETA for the destination, the Safety Altitude and fuel burn.
5. To select a fix near the half-way point of the leg and then proceed as normal. (Remind your student that although diversion navigation requires more attention to map reading (because he will not have had the benefit of detailed study of this route) he must stick to the Event Technique and maintain good Lookout.)
6. To update the NAVLOG once all calculations have been completed and advise ATC of his change of plan.

Stress that super-accurate calculations are not required. Given the distances involved and the minimum visibility limits required for VFR navigation, flying a heading within 5° and using an ETA within two minutes of the correct one will ensure that your student flies near enough to the diversion destination to be able to see and recognize it. However, calculating drift to the nearest 1⁄2 ° and then applying it the wrong way can result in a major heading error and getting lost, so emphasize the need to carefully review all calculations once en route to the diversion.

LOST PROCEDURES

  • Stress that accurate planning and execution are the best guards against getting lost and that if your student fails to spot a fix or turning point, he should not panic or fly aimlessly but stick to his flight plan and check methodically for any errors both in the accuracy of his flying (e.g. has he been flying heading 130° instead of the 103° required?) and his planning (has he applied drift in the wrong sense?). If
    he fails to locate the next fix-point, he should then consider that he could be lost. Teach him to seek help from ATC without delay either to regain his route, divert or return to base and that safety, in particular in relation to fuel reserves and daylight remaining is always the top priority.

 

  • Radio Aids Navigation

All navigation up to and including the Qualifying cross country is visual, based on the techniques covered above. Radio aids (including GPS) may not be used for tracking or as the primary means of navigation. The cross-cut of two VOR radials or a radial plus DME range can be used to take a confirmatory fix, as can GPS data. In addition, a cross-track radial or DME range can be useful as a good back-up to avoid overshooting a turning point.

Teach the following “dos and don’ts”:

a. Never use a VOR outside its Designated Operational Coverage (DOC).
b. Use S.T.I.F.D

Select – an appropriate aid (e.g. close to the beam for an along track cross-cut)

Tune – select the appropriate frequency

Identify – ensure the beacon identifier is correct

Flags -no warning flags showing

Display – display the information; make sure your student understands what the display means; is the information what he expects?

c. Always back up/cross check any radio aid position obtained.

COMMON FAULTS

  • Jumping to conclusions about fix points – the student “seeing” what he expects to see rather than what is actually there – is a common error. Ensuring that your student chooses good, unique fix-points is the best guard against mis- identification. But most faults result from over-concentration on map reading or overloading themselves with non-essential tasks – particularly fiddling with navigation aids – to the detriment of THREAT AND ERROR MANAGEMENT and the accuracy of flying and DR calculations. Insist on your student sticking to the event technique to avoid these problems. Teach your student to do only those tasks that are necessary and not to make work for himself.