maintaining the course

[indyaachen]

Maybe I am too thick while in air but I seem to learn more from these forums and asking for tips. So here it goes ...

My instructor keeps telling me that I need to stay the course. I find the pre-planning not that useful if there is some wind, even with WCA etc. calculated previosuly. The reality in air is different, more so for newbies.

Recently, I have started using a technique to keep tracking a course and I am wondering if that's what the experienced ones do something similar.

From a point I turn to the heading and aim for a feature (settlement, chimney, windmills, etc) in front of me. After a few minutes I could see that I am deviating while holding the heading. More pronouced the ground features are the easier it is. One could quickly add/subtract a few degrees to the heading to get the actual course. With all the visual checkpoints to note and other duties, I have found it an exhausting excercise.
Are there any instructors who could pass on some wisdom about this?

[Gertrude the Wombat]

Um ... yes ... well ... I do do the sums before taking off, and the results are usually pretty good, but every now and then the wind is, indeed, not what was forecast. And then I ... turn left a bit, or right a bit, until it works, pretty much as you say. And it works - I certainly don't bother with that "I'm half a mile to the left so I should alter course by 2.387 degrees to the right and then I'll be back on track in 123.87 seconds" mental arithmetic nonsense.

But how much is "a bit"? - somewhat like my mother's recipes ("put in some [ie an unspecified amount] so-and-so") it seems to come with experience (not that I've got very much, but enough for that).

[jamesgrainge]

With time seems to come a more natural feel for the wind and your drift. On my skills test using a diversion plotter gave me a heading of 100, almost instantly I could see that didn't work with my map, went to about 105 still no, then 110 looked better, told the examiner and turned up over the intended area. Vfr navigation in class G isn't an exact science. You'll get used to it.

[flybymike]

It sounds like you are feature crawling which is a fail in the skills test nav section as an unnaceptable form of navigation.

If using ground features for visual navigation is unacceptable, I’m stumped.....

[Nubboy]

The preferred method taught in the U.K., as reinforced at Instructor refresher seminars, is indeed to fly a constant heading over a known period of time. This heading is indeed pre calculated on the ground using a forecast wind. When a track deviation occurs then the student (candidate on a skill test) is expected to provide the instructor with a new nominated heading as well as explaining where and when they will regain track. This is the old black art of DR navigation.
Simply flying from from one visual feature to another does not prove the students skill at DR navigation. Accurate map reading is of course a pre requisite good visual navigation skills.
Having returned to ppl flying instruction after airline flying I've quickly seen it's an area where quite a few students struggle. Also like most instructors I've quickly found a few routes where obvious features aren't in over supply.
Phil

[Gertrude the Wombat]

but you need to have reason behind saying correcting 5° left
"I ended up a bit to the right of the last feature and 5° feels about right."

Unless the forecast error is catastrophic you'd start with 5° rather than 10°, yes? So it's almost always going to be 5°, yes? Given I'm not going to faff around with the odd degree or two until we get to the fine tuning, if then, as I can't fly that accurately anyway.

So, you start with 5°. If that doesn't work try 10°. Then fine tune.

[Jhieminga]

I've found that the 1 in 60 rule can often be used to good effect in these cases. So you've done your sums on the ground, you've started on the first of your navigation legs and you find out you're off track. If you can use the features on the ground to estimate how far off track you are, and how far along the track you are, it's then a fairly easy sum. If you've flown 60 miles and you're 1 mile off track, that's a 1 degree difference, so get back on track and adjust your heading by 1 degree. If you've flown 10 miles and you're 1 mile off track, the long side of the triangle is 1/6th of the original, so the angle will be 6 times as much, or a 6 degree change. If you've flown 10 miles and you're 3 miles off track, you multiply the original 1 degree by 6, and again by 3, to end up with an 18 degree change.

You can use this to figure out how to get back on track after a particular number of miles, but keep things simple for now and just try to figure out the correction angle. This method is really useful if you've got several legs that all point in the same general direction. If you've got a route planned with many large heading changes, you may not have many opportunities to use this. I always encourage students to practice some of these sums by themselves before they go flying. In practice you'll find that you generally are between 1 and 5 miles off course, and somewhere between 5 and 15 miles along your track. So practice with those numbers and after a while you will be able to quickly come up with the answer. Also, remember that a one degree difference isn't all that significant. So, if you're 10 miles along and one mile off, its 6 degrees correction, 12 miles along and one mile off, 5 degrees correction, 15 miles along and one mile off, 4 degrees correction. So just round off to those numbers and you'll be fine. Just don't forget to multiply if you're more than one mile off track.

[Nubboy]

http://gbnsr.org.uk/cft/VFR%20Navigation%20Part%203%20-%20The%20Standard%20Closing%20Angle%20Technique.ppsx
Above is a link to the Standard Closing Angle technique. Very very simple to use in practice. Just need to know actual True Airspeed and cross track error as a distance and a watch ⌚️. Amount of mental arithmetic needed is very little. However it does assume compass and DI aligned and you set course accurately over your turning point. Cheers Phil

[Capt Kremmen]

Simplify everything and catch up with the 21st century by using a GPS moving map backed up with a paper map ? It possesses the added benefit of keeping you out of CAS.

[piperboy84]

Yeap, getting thru the nav part of the PPL checkride is a pain in the ass. The good news is once you get your ticket it’s plain sailing (pun intended) from then on, get her trimmed out and sit back with your elbow out the window, crank up the tunes, crack open the tea flask or even fire up that fag you’ve been gasping for since startup, and enjoy the ride. Just remember to give the rudder the odd kick every now and then to keep the wee airplane symbol centerd on the magenta line of the Satnav. Simples!

[piperboy84]

I agree that the average PPL will just use a GPS so I always offered to come up for free with a student after they passed and show them how to use a GPS properly rather than hit DTO and bust airspace enroute etc.. however I stick by you need to understand the basics to use the toys. I've been in the position in an airliner of massive technical issues needing to look out the window, pick up a chart and navigate old school while out of radar coverage.

That “rubber banding” feature these new units have to drag the route and create waypoints on the fly is the business.

[Fl1ingfrog]

There are as many navigation techniques as there are proponents of them. Nubboy, Beagle will be thrilled to see you advocating SCA. I do not teach this myself though.

I'm dismayed to read some sloppy suggestions that advocate changing heading a little bit here and a little bit there. Studies show that one reason pilots become lost is doing just that. It is critical that the pilot is taught a simple technique that allows reasoning, and will support them, if/when under stress and unable to confirm their position or lost.

Whatever the technique taught it should NOT be over demanding. It must be possible for the pilot to relax and fly accurately the preplanned/revised heading; wings level and in balance for at least 8-10 minute periods.

Jhieminga you have described a calculation using the 1:60 rule, not the rule itself, a common mistake and so not helpful.

Flying feature to feature (feature crawling) is risky although sounds simple. Until you arrive at the next feature you cannot know it is the place you thought it was and therefore be miles off track and lost.

indyaachen what is the technique your instructor is teaching you, or more likely by the sounds of it, trying to teach you? I'm loath to comment further without having the full information.

[rotorfossil]

Feature tracking works OK when there is good visibility. It falls down when the vis is poor or it’s raining etc, not uncommon in the UK. Unfortunately it can become a habit because nav is rarely taught in poor vis.
You have to have a systematic technique that works in all conditions ( and when the GPS goes belly up ). It is based on the idea that if you accurately steer a planned heading for a given time to a recognisable feature, you then have a basis for working out a correction which will return you to track, and when you regain track, an alteration which then maintain the track. This system corrects for errors in the forecast wind. It doesn’t however correct for inaccurate steering of the headings, a much more common fault.

[Nubboy]

Nice thread. Fl1ngfrog has summed it nicely. Accurate balanced flying is the key. Gps is the practical every day solution once you have a licence. The addition of being able to demonstrate basic vor use on the skill test is an advance. Our fleet has garmin 430 coupled to the number 1 obs. Use of this in both vor and gps mode is covered in the pre test revision phase of the syllabus.
Just bear in mind the op was asking for help whilst learning.

[Vilters]

It is like riding a motorcycle. =>The further out you look the more stable the ride and the safer you are.

Do the math on the ground.
But wind changes over distance AND over altitude.
Very early in the flight, you will find out if the actual wind direction and speed are what was predicted. The rest of the flight is simply adapting the calculated routes to the actual wind.

[wiggy]

Nubboy, Beagle will be thrilled to see you advocating SCA. I do not teach this myself though.

"lurker" checking in...agree with the above.....but then I'm a similar era to Beagle, and taught similar ....certainly for medium level Nav, track crawling came much later in the game..


As I rcall it back in the day of teaching basic Nav the crux point was that between the dreaded "events" in the event cycle you looked out and flew accurately. (and BTW when the chart was picked up it was held up at almost eye level)

Given the number of midairs I've read about recently I would have thought that still apllies, which I guess begs the question from a non PPLer - is Nav by ipad/track crawl compatible with a good lookout?

[scifi]

On my Skills Test my halfway point was a Motorway junction, which I arrived at 400 yards to the left. I mentioned this to the Examiner and said that I was quite happy with that. He then asked what I would do, I said I could side-step over to the junction, then continue as normal, which is what we did.
However the last half of the flight saw us 2 miles to the right of our airfield, so that was not so good. I think we must have had a wind shift, or DI drift..!
I don't think I have ever used DR again, I only ever go on scenic flights, where I might even circle a landmark, if it is interesting enough.
.

[jamesgrainge]

Yeap, getting thru the nav part of the PPL checkride is a pain in the ass. The good news is once you get your ticket it’s plain sailing (pun intended) from then on, get her trimmed out and sit back with your elbow out the window, crank up the tunes, crack open the tea flask or even fire up that fag you’ve been gasping for since startup, and enjoy the ride. Just remember to give the rudder the odd kick every now and then to keep the wee airplane symbol centerd on the magenta line of the Satnav. Simples!

Finally, someone who understands what flying is all about :ok:

[Jhieminga]

Jhieminga you have described a calculation using the 1:60 rule, not the rule itself, a common mistake and so not helpful.
Indeed I did, as I have found that this is the bit that turns out to be the most helpful to many students. In the end, there are several approaches to navigating around the skies in a small aircraft and it is up to the thread starter to take away what he needs and/or feels comfortable enough with to use in his lessons. I would also strongly recommend a chat with his instructor about this before the next navigation lesson. Many instructors have a favourite method that they use and/or teach, but coordinating beforehand which method will be used/practiced is always useful. I for one am always interested in learning new techniques and it won't be the first time that a student will come up with something new or different, providing me with another tool in my bag of tricks.

For more about the 1:60 rule, see here: https://www.pprune.org/flying-instructors-examiners/13346-1-60-rule-please-explain.html

[rarelyathome]

Indeed I did, as I have found that this is the bit that turns out to be the most helpful to many students. In the end, there are several approaches to navigating around the skies in a small aircraft and it is up to the thread starter to take away what he needs and/or feels comfortable enough with to use in his lessons. I would also strongly recommend a chat with his instructor about this before the next navigation lesson. Many instructors have a favourite method that they use and/or teach, but coordinating beforehand which method will be used/practiced is always useful. I for one am always interested in learning new techniques and it won't be the first time that a student will come up with something new or different, providing me with another tool in my bag of tricks.

For more about the 1:60 rule, see here: https://www.pprune.org/flying-instructors-examiners/13346-1-60-rule-please-explain.html

I learned using the 1:60. I teach the SCA for a good reason. NM off track, turn 40 deg (for most PPL training ac) L or R for the number minutes corresponding to the number of NM off track, turn back on heading. Reassess if its wrong again and again and you are convinced you are flying accurately - either wind or DI alignment and correct as appropriate. What could be simpler?

[Kerosene Kraut]

How far apart are the VFR waypoints we are talking about from each other? How far off could you be blown then? Maybe lining up places a little closer together might do the trick?

[Gertrude the Wombat]

How far apart are the VFR waypoints we are talking about from each other?
Well quite. It depends where you live - talking about how many miles off to one side you are after 30 miles flying might be all very well in Australia or the USA but there are very few places you can go that far in a straight line in the south of England!

[Fl1ingfrog]

I have attached a full explanation of the 1:60 rule as a pdf. I'm sorry if this is cumbersome, I don't know of a simpler way.

If you were to use this method it requires repeating for a closing angle to the next waypoint or destination if that is the choice. Otherwise using the discovered angle off track double it toward the track to regain in the same distance and time or treble it to regain track in half the distance and time.

As can only be expected there are various 1:60 methods such as using inverse fractions, particular used by commercial pilot schools, for a number of years, who preferred closing angle direct to destination/waypoint for reasons that do not bear explanation.

[indyaachen]

A lot of information here, but it seems that the common message is that I am doing it wrong with 'feature crawling'. My question then is how can one fly a calculated heading without constantly looking at the instruments.
Of course, when I select feature ahead of me, it is just for the reference to keep me within a few degrees of the heading until the next checkpoint. Am I expected to fly in the straight line? I severly doubt my ability there.

What is my instructor telling me? well ....
Our club operates with a different instructor on each day of the week, and therefore I have now flown with almost every instructor. I don't like it but I don't have much choice there. I reckon my difficulties are partly due to every instructor teaching the same thing slightly different.

[Fl1ingfrog]

indyaachen

The earth is the best and most reliable instrument, it doesn't suffer from precession nor topple.

Having set heading and noted the time; check/adjust the HI against the wet compass then select a good reference feature, well ahead, as close as possible to the horizon. Revise the heading if necessary. The reference doesn't need to be on the nose, to one side will do but keep the relationship constant. You can even use a cloud or cloud formation, it won't change much in the short time you will be using it. Complete your FREDA/LIFE checks or whatever you have been taught.

As you get closer to your reference you will need to revise it. During this time relax, if you maintain wings level and fly in balance then your heading will remain constant and height maintenance will be good. You do not have to constantly stare at the HI. The more you roll or yaw the more you will cause precession of the HI. Not only for safety, though important, having your head up and looking out you will naturally maintain spacial awareness. As light changes so does the look of the world around you which can be confusing. So often the pilot believes they are lost because of this phenomena and air traffic confirm they are exactly where they expect to be.

DR navigation is not about flying in straight lines (although nice if it happens) but rather about flying a constant heading and speed. At intervals, I would suggest never less than 8-10 minutes, calculate any off track and time errors, you have now found the actual w/v. Regain track, check you HI against the wet compass and having done so revise your heading by the value of the track error.

Any club that allows instructors to do their own thing is unacceptable and I have never allowed it. Particularly in a situation where the student must fly with a range of instructors during their training.

[scifi]

Having been the Navigator in a Rally Car, I soon got to realise that where the bonnet was pointing was not necessarily the direction we were traveling... The old joke was that you cleaned the side windows so that you could see where you were going.
It is exactly the same with flying in a crosswind. If you have 10 degrees of drift, then you are not going where the prop-spinner is pointing... More likely it coincides with the pillar on the left, or the edge of the bonnet to the right. So look for landmarks in either of those directions to aim at, and fly over.
.

[antiseptic]

Most pilots, even PPLs these days (due to GPS etc), don't navigate enough with compass, stopwatch and map to realise that with a bit of experience it's uncanny how accurately you can do it.
I used to regularly fly hundreds of kilometers over featureless African bush and swamp with the GPS switched off for the practice. I was struck by two things:

(a) With practice you quickly 'sense' after setting course how much drift you have and how much to correct by. After flying regularly like this for a bit you get an intuition for it; no need for fancy mental calculations.

(b) If you fly the same route enough, even if it is featureless, you know where you are simply by such things as slight changes in the colour of the ground etc.

However, technological aids (which I am all for by the way) mean people rarely fly enough the old fashioned way to get really good at it.

Golden rule of course - stick to your heading like glue unless youhave reason to change it.

[Gertrude the Wombat]

Then there's the "how to find a clearing in the Burmese jungle" game, when the weather forecasting is sufficient to tell you whether the wind is coming from the left or the right but not how strong it is accurately enough for you to end up over a tiny clearing in a vast jungle. And having done your dead reckoning and not seeing the clearing, do you turn left or right? - you haven't a clue.

Instead, fly desired track for heading, for the calculated time. You then know you're downwind of the destination, so turn 90 degrees upwind and fly until you spot it.

[Heston]

The Sir Francis Chichester method. Yes it works. It's also a good navigation technique for finding your way on land - the army teach it, and orienteering people use it.

[Gertrude the Wombat]

(PS: shouldn't need saying, but these days ...

DON'T TRY THIS AT HOME CHILDREN

Not if you're within a couple of hundred miles of controlled air space, anyway.)