Navigation - big problems, need HELP!
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eyeingthesky,
I don't think that that was the question though was it. The guy is having trouble with VFR NAVIGATION and is obviously struggling to relate what is on his map to what is on the ground. There also appears to be a lack of confidence in his planning from what I can gather.
No one was asking about how to work out crosswind limits etc. If the flight is planned properly and navigated and flown correctly there should be no scope for flying off track and getting lost.
And seeing as how we appear to be taking cheap shots, if you keep finding yourself in the position that requires you to work out how to get back on track, then maybe you should do a bit more nav training. <img src="wink.gif" border="0">
I don't think that that was the question though was it. The guy is having trouble with VFR NAVIGATION and is obviously struggling to relate what is on his map to what is on the ground. There also appears to be a lack of confidence in his planning from what I can gather.
No one was asking about how to work out crosswind limits etc. If the flight is planned properly and navigated and flown correctly there should be no scope for flying off track and getting lost.
And seeing as how we appear to be taking cheap shots, if you keep finding yourself in the position that requires you to work out how to get back on track, then maybe you should do a bit more nav training. <img src="wink.gif" border="0">
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As somebody who is severly directionaly challenged I had a few problems with navigation. However I'm surprised that no ones mentioned the best advice I was given whilst training. On departure make sure that you pick a very obvious landmark to do a gross error check with. By doing this you can check your drift, instruments and that your not flying a reciprocal or just plain mis-read heading. Once you're established on track pick an obvious point on track and fly to it, as you approach your aiming point pick another. That way you tend to keep your head out of the office which helps you fly more smoothly and keep a good look out. Works for me most of the time. Also flying P2 is a big help. When you have time to look around and not worry about driving its a lot easier to recognise features and how they compare to the map.
Keep at it if they could teach me how to do it they can teach any one
Keep at it if they could teach me how to do it they can teach any one
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eyeingthesky....
I think Bow's right really. Mental load is very high when you are learning.... minimise all the numbers stuff, use visual clues as much as possible.
X-wind landings? I've never used precise calculations as I've turned onto finals and been given the wind speed & dir. I visualise it in my mind, I feel it and see it and I know whther it's going to be out of limits FOR ME (which is perhaps more limiting than the aircraft) to handle.
Besides, you can be given a speed and direction which may be variable... the tower cant tell you what it will do, though they'll have a reasonable idea (in which case they'll say "gusting" or "variable").
And if I shouldnt be flying? OK maybe I'd better stop now after 30+ years PPL-ing without an accident.....(touches as many pieces of wood as he can....)
I like the previous comment about significant landmarks and assessing drift that way... I know many experienced VFR pilots who flight plan for nil wind conditions and then use visual assessment to adjust once they are up, on the basis that the forecast wind is never the same as the actual.
Bet this sets the cat amongst the pidgeons...... <img src="rolleyes.gif" border="0">
I think Bow's right really. Mental load is very high when you are learning.... minimise all the numbers stuff, use visual clues as much as possible.
X-wind landings? I've never used precise calculations as I've turned onto finals and been given the wind speed & dir. I visualise it in my mind, I feel it and see it and I know whther it's going to be out of limits FOR ME (which is perhaps more limiting than the aircraft) to handle.
Besides, you can be given a speed and direction which may be variable... the tower cant tell you what it will do, though they'll have a reasonable idea (in which case they'll say "gusting" or "variable").
And if I shouldnt be flying? OK maybe I'd better stop now after 30+ years PPL-ing without an accident.....(touches as many pieces of wood as he can....)
I like the previous comment about significant landmarks and assessing drift that way... I know many experienced VFR pilots who flight plan for nil wind conditions and then use visual assessment to adjust once they are up, on the basis that the forecast wind is never the same as the actual.
Bet this sets the cat amongst the pidgeons...... <img src="rolleyes.gif" border="0">
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On the subject of x-wind landings quickly, I agree with poetpilot. I take in mind where the wind is coming from and it's strength and visualise it in my mind.
As a low hour PPL (56hr) i'd like to think i'm responsible enough not to go up there when the wind is very strong and likely to be outside limits until i've gained more experience. Like people keep saying, the PPL is a licence to learn. It's dangerous to jump in with great size 9's straight away. Many a cocky driver has come unstuck soon after passing their test and these ain't cars we play with - they're potentially far more threatening to our health.
As a low hour PPL (56hr) i'd like to think i'm responsible enough not to go up there when the wind is very strong and likely to be outside limits until i've gained more experience. Like people keep saying, the PPL is a licence to learn. It's dangerous to jump in with great size 9's straight away. Many a cocky driver has come unstuck soon after passing their test and these ain't cars we play with - they're potentially far more threatening to our health.
All you could possibly want to know about SCA:
<a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000301&p=" target="_blank">http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000301&p=</a>
<a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000090&p=" target="_blank">http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000090&p=</a>
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<a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000090&p=" target="_blank">http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=5&t=000090&p=</a>
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Poet pilot
Surely 'experienced' VFR pilots plan with no wind because they rely on VOR and GPS to see them to their destination.
Not quite the same for a beginner, and the 'experienced' could find themselves a little short of fuel if they don't check the winds before long flights or even short ones in some parts of Europe.
I find variations in the weather, season and sun angle, not to mention the occasional snow covered day, can all make visual reference recognition either easy or confusing.
Maybe confidence could be regained by initially trying for the perfect day.
Surely 'experienced' VFR pilots plan with no wind because they rely on VOR and GPS to see them to their destination.
Not quite the same for a beginner, and the 'experienced' could find themselves a little short of fuel if they don't check the winds before long flights or even short ones in some parts of Europe.
I find variations in the weather, season and sun angle, not to mention the occasional snow covered day, can all make visual reference recognition either easy or confusing.
Maybe confidence could be regained by initially trying for the perfect day.
Or if you can't be bothered sifting through the pages of info (and with apologies to BEagle from whose post this was cribbed):
STANDARD CLOSING ANGLE
1. Establish your distance off track.
2. Turn towards track by a Standard Closing Angle of 60/(TAS in miles per minute) i.e. 40 deg for a 90KIAS Cherokee, 30 deg for a 120KIAS Bulldog.
3. Hold that heading for the same NUMBER of minutes as you were miles off track , i.e. 3 minutes if you were 3 miles off track.
4. Turn back onto original heading , recheck DI is synch'd and the rudder trim is correctly stopping flight with a constant yaw.
5. Adjust timing by adding 1/3 of the time spent on the Standard Closing Angle at 90KIAS or 10 sec per minute at 120KIAS.
STANDARD CLOSING ANGLE
1. Establish your distance off track.
2. Turn towards track by a Standard Closing Angle of 60/(TAS in miles per minute) i.e. 40 deg for a 90KIAS Cherokee, 30 deg for a 120KIAS Bulldog.
3. Hold that heading for the same NUMBER of minutes as you were miles off track , i.e. 3 minutes if you were 3 miles off track.
4. Turn back onto original heading , recheck DI is synch'd and the rudder trim is correctly stopping flight with a constant yaw.
5. Adjust timing by adding 1/3 of the time spent on the Standard Closing Angle at 90KIAS or 10 sec per minute at 120KIAS.
Beethoven - e-mail me with an address and I'll send you an explanation of SCA if you wish....! But for anyone else who wants to know more, herewith some words about the Standard Closing Angle technique:
1. Most PPL text books give students a number of suggestions concerning methods of visual navigation. All these are based on the well-proven ‘1 in 60’ method which is a technique for calculating correction angles using estimates of off-track distance errors. Equally, it is also possible to make track corrections based upon estimates of angular track errors, a technique which is still quite popular.
2. However, most of these methods suffer from the drawbacks of either requiring relatively difficult mental arithmetic or correcting not back to the planned track with its associated pre-planned visual fixes, but direct to the next planned turning point. Recent advice from senior ex-CAA Examiners suggests that a rigorous navigation technique is required which instead does allow pilots to correct back onto their pre-planned track. Traditional techniques have not provided pilots with a simple method for achieving this; however a method originated in the RAF is available which makes track correction from observed off-track distances extremely straightforward
3. It works like this: If you realise that you are A miles off track and wish to fly B miles back on to track, then you need to turn through an angle C whose sine is equal to A/B. Now the 1 in 60 rule tells us that C is more or less equal to (A/B)x60 and if you fly your distance B at v miles per minute for t minutes, then C = (60/v)x(A/t). If A and t are made numerically the same, that is you fly for the same number of minutes as your number of miles off track, then A = t and a Standard Closing Angle C of (60/v) can be used where v is expressed in miles per minute. Hence the SCA at 360 kts is 10°, at 120 kts it is 30° and at 90 kts the SCA is 40°.
4. This method is really only completely accurate when TAS equals GS; it was originally used for navigation in fast aircraft at low level where the difference between these two values was insignificant. The error will be greater at lower speeds, but is quite acceptable as the SCA technique assists pilots in reducing track error to a point from which readily identifiable pre-planned visual fixes can be observed and overflown. Similarly, timing errors will be introduced with a large SCA as the aircraft’s along track velocity (more trigonometry, sorry!) is v cos C rather than v. This can be overcome either by reducing the SCA and increasing the correction time correspondingly, or by making an appropriate timing correction. In practice it is better to return to track as soon as possible, but only if a simple method for correcting the timing error can also be achieved.
5. Considering the PA28 with a 90 kt cruising speed, things now become quite simple. The SCA is 40° and cos 40° is 0.766 which is as near as makes no odds 3/4, so what should have taken 3 minutes on track will now take 4 minutes on a 40° SCA, i.e. 1/3 longer. These values will later be used in summarising the SCA method for use by PPL students cruising at 90 kts. (In a Warrior at 105 kts, theoretically the SCA is 34° and the corresponding ETA delay is 1/4 the track correction time, but for all intents and purposes it’s easier just to stick to the same figures as for the Cherokee).
6. It is also necessary to examine why the aircraft was off-track in the first place. Assuming that pre-flight planning was correctly completed, several factors could have caused the aircraft to be off-track. For example, was the DI correctly set against the compass and was the slip ball properly centred? Did the pilot fly the aircraft accurately on the planned heading? If the answer to all those questions is yes, then the only possible cause of the error (barring ATC or divine intervention) must be that the wind velocity was other than the forecast value – a not unknown phenomenon! Having regained track, due correction can also be made for the change in drift which can readily be deduced by reference to a drift line drawn on the map. Because, if the pilot flew the aircraft accurately and yet discovered a track angle error of D°, then when back on track and with the DI re-aligned, the heading may be altered by the same angle D to correct for drift. In the correct direction, of course!
7. To assist in making these estimates, consider now the subject of map preparation. The start point and turning points should be marked with a circle and the track between drawn in. Timing marks every 6 minutes may be added as must the exact elapsed time at readily identifiable visual fixes roughly corresponding to easy fractions of the way along the leg (to make proportional timing correction reasonably straightforward) and at the turning point. A single 10° fan line from the start point for each leg should be drawn, to allow assessment and correction of drift error as described in para 6 above. Finally the heading (not track) for each leg should be written on the map and a note made of the W/V at the level being flown together with the associated max drift value, as well as the safety altitude. Estimating distance from the CAA ½ million chart is straightforward enough by reference to the known dimensions of ATZs, MATZs and, of course, the latitude marks.
8. Using the SCA technique is very straightforward. Let us imagine that we have been accurately flying the first leg of our navigation exercise at 90 kts on a heading of 040° when we notice that we are 4 miles left of track with some 7° of drift error as deduced from our single 10° fan line. The first correction is to turn right onto a heading of 080° and then to time for 4 minutes as we head back towards track. During this 4 minutes we can first reassess that it really was a 4 mile error and then jot down on the log that our ETA at the turning point will be 4/3 of a minute later than calculated and that there’ll be a 7° drift correction to apply when we’re back on track. When our 4 minutes are up, we turn back onto our original heading plus our drift correction, i.e. on to 047° in this example and recheck that the DI is properly aligned with the magnetic compass. With any luck and assuming that the wind doesn’t change yet again, our navigation exercise should now continue pretty well on track and we should only need to note the passing of visual fix points to revise the ETA at the turning point.
9. Although SCA has its sceptics, it is a very simple and easy way for pilots to correct navigation errors and to regain their pre-planned track and it’s the method I require to be taught to all new students. But none of this is going to be much use if a pilot hasn’t planned accurately in the first place, flown accurately or thought ahead!
BEagle
[ 11 January 2002: Message edited by: BEagle ]</p>
1. Most PPL text books give students a number of suggestions concerning methods of visual navigation. All these are based on the well-proven ‘1 in 60’ method which is a technique for calculating correction angles using estimates of off-track distance errors. Equally, it is also possible to make track corrections based upon estimates of angular track errors, a technique which is still quite popular.
2. However, most of these methods suffer from the drawbacks of either requiring relatively difficult mental arithmetic or correcting not back to the planned track with its associated pre-planned visual fixes, but direct to the next planned turning point. Recent advice from senior ex-CAA Examiners suggests that a rigorous navigation technique is required which instead does allow pilots to correct back onto their pre-planned track. Traditional techniques have not provided pilots with a simple method for achieving this; however a method originated in the RAF is available which makes track correction from observed off-track distances extremely straightforward
3. It works like this: If you realise that you are A miles off track and wish to fly B miles back on to track, then you need to turn through an angle C whose sine is equal to A/B. Now the 1 in 60 rule tells us that C is more or less equal to (A/B)x60 and if you fly your distance B at v miles per minute for t minutes, then C = (60/v)x(A/t). If A and t are made numerically the same, that is you fly for the same number of minutes as your number of miles off track, then A = t and a Standard Closing Angle C of (60/v) can be used where v is expressed in miles per minute. Hence the SCA at 360 kts is 10°, at 120 kts it is 30° and at 90 kts the SCA is 40°.
4. This method is really only completely accurate when TAS equals GS; it was originally used for navigation in fast aircraft at low level where the difference between these two values was insignificant. The error will be greater at lower speeds, but is quite acceptable as the SCA technique assists pilots in reducing track error to a point from which readily identifiable pre-planned visual fixes can be observed and overflown. Similarly, timing errors will be introduced with a large SCA as the aircraft’s along track velocity (more trigonometry, sorry!) is v cos C rather than v. This can be overcome either by reducing the SCA and increasing the correction time correspondingly, or by making an appropriate timing correction. In practice it is better to return to track as soon as possible, but only if a simple method for correcting the timing error can also be achieved.
5. Considering the PA28 with a 90 kt cruising speed, things now become quite simple. The SCA is 40° and cos 40° is 0.766 which is as near as makes no odds 3/4, so what should have taken 3 minutes on track will now take 4 minutes on a 40° SCA, i.e. 1/3 longer. These values will later be used in summarising the SCA method for use by PPL students cruising at 90 kts. (In a Warrior at 105 kts, theoretically the SCA is 34° and the corresponding ETA delay is 1/4 the track correction time, but for all intents and purposes it’s easier just to stick to the same figures as for the Cherokee).
6. It is also necessary to examine why the aircraft was off-track in the first place. Assuming that pre-flight planning was correctly completed, several factors could have caused the aircraft to be off-track. For example, was the DI correctly set against the compass and was the slip ball properly centred? Did the pilot fly the aircraft accurately on the planned heading? If the answer to all those questions is yes, then the only possible cause of the error (barring ATC or divine intervention) must be that the wind velocity was other than the forecast value – a not unknown phenomenon! Having regained track, due correction can also be made for the change in drift which can readily be deduced by reference to a drift line drawn on the map. Because, if the pilot flew the aircraft accurately and yet discovered a track angle error of D°, then when back on track and with the DI re-aligned, the heading may be altered by the same angle D to correct for drift. In the correct direction, of course!
7. To assist in making these estimates, consider now the subject of map preparation. The start point and turning points should be marked with a circle and the track between drawn in. Timing marks every 6 minutes may be added as must the exact elapsed time at readily identifiable visual fixes roughly corresponding to easy fractions of the way along the leg (to make proportional timing correction reasonably straightforward) and at the turning point. A single 10° fan line from the start point for each leg should be drawn, to allow assessment and correction of drift error as described in para 6 above. Finally the heading (not track) for each leg should be written on the map and a note made of the W/V at the level being flown together with the associated max drift value, as well as the safety altitude. Estimating distance from the CAA ½ million chart is straightforward enough by reference to the known dimensions of ATZs, MATZs and, of course, the latitude marks.
8. Using the SCA technique is very straightforward. Let us imagine that we have been accurately flying the first leg of our navigation exercise at 90 kts on a heading of 040° when we notice that we are 4 miles left of track with some 7° of drift error as deduced from our single 10° fan line. The first correction is to turn right onto a heading of 080° and then to time for 4 minutes as we head back towards track. During this 4 minutes we can first reassess that it really was a 4 mile error and then jot down on the log that our ETA at the turning point will be 4/3 of a minute later than calculated and that there’ll be a 7° drift correction to apply when we’re back on track. When our 4 minutes are up, we turn back onto our original heading plus our drift correction, i.e. on to 047° in this example and recheck that the DI is properly aligned with the magnetic compass. With any luck and assuming that the wind doesn’t change yet again, our navigation exercise should now continue pretty well on track and we should only need to note the passing of visual fix points to revise the ETA at the turning point.
9. Although SCA has its sceptics, it is a very simple and easy way for pilots to correct navigation errors and to regain their pre-planned track and it’s the method I require to be taught to all new students. But none of this is going to be much use if a pilot hasn’t planned accurately in the first place, flown accurately or thought ahead!
BEagle
[ 11 January 2002: Message edited by: BEagle ]</p>
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...and, Beagle, that's all very well if the student KNOWS that he /she IS 4NM off track (or whatever).
Aren't there some distinct aspects to all this...
1. Planning
2. In-flight assessment of how plan must be modified
3. Knowing where you are at a given point in time
4. Knowing where you should be at a given.....
3a & 4a - Knowing where you are supposed to be going and when at a given.......
5. What you do about it
6. Planning for contingencies
(probably more).
Somehow, this has got to be methodically imparted to the student so that they can take it on board without mental overload & subsequent brain-death in flight.
Sorry, havent got all the answers, except that students should ground-study as much as poss to reduce the load of thinking in new ways whilst airborne & as said before, know their maps well.
On the other thing re: nil wind planning...
1.No, not suitable for students & sorry to divert the thread
2.The people I've seen doing it dont have nav gear in their aircraft so they dont use VORs. Those that use GPS should only use it as a secondary aid.
3. Yes, fuel management is important. To ignore signifcant headwind components will obviously give a problem. And accurate timekeeping throughout the trip is essential to monitor and adjust the plan as required.
4. If you dont plan contingency diversions (incl checking where and when fuel is available) then its not a proper flight plan.
Aren't there some distinct aspects to all this...
1. Planning
2. In-flight assessment of how plan must be modified
3. Knowing where you are at a given point in time
4. Knowing where you should be at a given.....
3a & 4a - Knowing where you are supposed to be going and when at a given.......
5. What you do about it
6. Planning for contingencies
(probably more).
Somehow, this has got to be methodically imparted to the student so that they can take it on board without mental overload & subsequent brain-death in flight.
Sorry, havent got all the answers, except that students should ground-study as much as poss to reduce the load of thinking in new ways whilst airborne & as said before, know their maps well.
On the other thing re: nil wind planning...
1.No, not suitable for students & sorry to divert the thread
2.The people I've seen doing it dont have nav gear in their aircraft so they dont use VORs. Those that use GPS should only use it as a secondary aid.
3. Yes, fuel management is important. To ignore signifcant headwind components will obviously give a problem. And accurate timekeeping throughout the trip is essential to monitor and adjust the plan as required.
4. If you dont plan contingency diversions (incl checking where and when fuel is available) then its not a proper flight plan.
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SCA was discussed at the last FI seminar I went to and most people did not really like it, as said, it works best for high speed aircraft - not the best discription of most PPL training machines.
If you want to get back on track, just double your track error (assuming less than half way along) and fly for as long as you have already gone on that leg, then turn the other way by half as much.
If you want to get back on track, just double your track error (assuming less than half way along) and fly for as long as you have already gone on that leg, then turn the other way by half as much.
foxmouth - which seminar? I went to an ETA one and the method was commended to the audience who agreed with it. Shame it was explained so poorly. I've also seen notes from another seminar giving an incorrect and fundamentally flawed explanation...
The double-the-error-for-the-same-time 'method' assumes that a constant error has been flown and that you can afford to stay off track for the same amount of time as you have already been off track. It's old-fashioned and inadequate.
SCA+MDR=KISS........
The double-the-error-for-the-same-time 'method' assumes that a constant error has been flown and that you can afford to stay off track for the same amount of time as you have already been off track. It's old-fashioned and inadequate.
SCA+MDR=KISS........
"Trust Me"
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"The double-the-error-for-the-same-time 'method' assumes that a constant error has been flown and that you can afford to stay off track for the same amount of time as you have already been off track."
That's the one I use -simple but effective. Also works for sailing.
DOC
That's the one I use -simple but effective. Also works for sailing.
DOC
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AOPA seminar at Cambridge.
I dont see that SCA works any better than double TE if your error has not been constant, and as for KISS, try READING your explanation. With the time corrections as well as the heading corrections, Simple, I think not! <img src="eek.gif" border="0">
The main advantage to SCA is it gets you back on your origional track earlier, but there are other, to my mind simpler ways of achieving this, also if you have position checks every 6-12 mins you should be making the correction (double TE or otherwise) BEFORE it stretches out to a long leg.
[ 13 January 2002: Message edited by: foxmoth ]</p>
I dont see that SCA works any better than double TE if your error has not been constant, and as for KISS, try READING your explanation. With the time corrections as well as the heading corrections, Simple, I think not! <img src="eek.gif" border="0">
The main advantage to SCA is it gets you back on your origional track earlier, but there are other, to my mind simpler ways of achieving this, also if you have position checks every 6-12 mins you should be making the correction (double TE or otherwise) BEFORE it stretches out to a long leg.
[ 13 January 2002: Message edited by: foxmoth ]</p>
foxmouth - my explanation is comprehensive so that those of a mathematical persuasion can understand its derivation if they won't accept the simple 60/groundspeed in miles per minute result. Practically I wouldn't necessarily expect students to; all they have to be able to do in flight is to add or subtract 40 and correct things when they’ve flown the SCA time back to track. KISS? Definitely. Timing correction isn't that essential for those poor souls who can't divide by 3.... Why not give it a try - everyone I've taught it to finds it vastly easier than any other system.
It was the AOPA notes I read which had a poor explanation of SCA - and total nonsense regarding timing correction!!
It was the AOPA notes I read which had a poor explanation of SCA - and total nonsense regarding timing correction!!
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Beagle,
Two things strike me here, firstly you are dealing with BOTH distance off track, AND drift - using double TE or TE + CA just uses the angles.
The second point is that if you are teaching this to students they NEED to understand it - it is fine saying turn 40 degrees, but then they convert to a much faster aircraft ( a twin maybe?) and the figures change. I do know this technique and did so before the seminar, I just found it more involved than needed for PPL nav.
At the end of the day the thing that matters is it works for you and your students, I have tried both and found what works best for me and those I teach, I think we will just have to differ on this one. <img src="wink.gif" border="0">
[ 14 January 2002: Message edited by: foxmoth ]</p>
Two things strike me here, firstly you are dealing with BOTH distance off track, AND drift - using double TE or TE + CA just uses the angles.
The second point is that if you are teaching this to students they NEED to understand it - it is fine saying turn 40 degrees, but then they convert to a much faster aircraft ( a twin maybe?) and the figures change. I do know this technique and did so before the seminar, I just found it more involved than needed for PPL nav.
At the end of the day the thing that matters is it works for you and your students, I have tried both and found what works best for me and those I teach, I think we will just have to differ on this one.
<img src="wink.gif" border="0">[ 14 January 2002: Message edited by: foxmoth ]</p>
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I vaguely recall wrestling with this stuff early on in navexs and the first couple of hundred hours. These days I totally ignore it, it is just another set of questions that can be answered in an exam and has very little use in VFR flying.
How do you find out how many miles off track you are? Well typically by looking out the window! Do that and you know where you are (you must do how else do you know you are 5.8 miles east of track?). So if you know where you are and where you want to go, any of us can set course within 10 degrees - which is more than close enough. Simple VFR pilotage will then take you to your destination.
All these mathematical techniques really belong in the IFR area where you might get a decent VOR,DME or NBD cut which would give you a sudden 'you are x miles offtrack', for VFR flying putting an X on the map every 5 to 10 miles is so much more reliable that these techniques are nothing more than mind games.
If people are setting course and attempting to maintain it within a couple of degrees to arrive over some point within a couple of minutes of an arbitarily calculated time, then I would suggest they are not getting much out of their flying. They might as well use a flight sim and say a fortune! I fly to look out the window and visit places. If I ever fly a straight line it would be over the sea with no land in sight, otherwise enjoy our scenery and know where you are!
Of course you still have to know this stuff to pass the exams!!
How do you find out how many miles off track you are? Well typically by looking out the window! Do that and you know where you are (you must do how else do you know you are 5.8 miles east of track?). So if you know where you are and where you want to go, any of us can set course within 10 degrees - which is more than close enough. Simple VFR pilotage will then take you to your destination.
All these mathematical techniques really belong in the IFR area where you might get a decent VOR,DME or NBD cut which would give you a sudden 'you are x miles offtrack', for VFR flying putting an X on the map every 5 to 10 miles is so much more reliable that these techniques are nothing more than mind games.
If people are setting course and attempting to maintain it within a couple of degrees to arrive over some point within a couple of minutes of an arbitarily calculated time, then I would suggest they are not getting much out of their flying. They might as well use a flight sim and say a fortune! I fly to look out the window and visit places. If I ever fly a straight line it would be over the sea with no land in sight, otherwise enjoy our scenery and know where you are!
Of course you still have to know this stuff to pass the exams!!
ENTREPPRUNEUR
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Can I remind everyone that beam's problem was "I've 'developed' a problem where I just can't seem to 'line up' the map and the ground".
When you know where you are it is trivial to say the least to get back to where you want to be. If you are left of track you just steer 5, 10 or 15 degrees right. It doesn't matter critically which - you'll soon see if it is having the desired effect.
When you know where you are it is trivial to say the least to get back to where you want to be. If you are left of track you just steer 5, 10 or 15 degrees right. It doesn't matter critically which - you'll soon see if it is having the desired effect.
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Since beammeup hasn't posted in a while he's possibly stopped reading this long thread - but here's another suggestion anyway.
I find that navigational problems with students often come down to a personal lack of confidence, rather than a deficiency in his/her technique. From time to time I've sat quietly while a student flies bang over the correct checkpoint at exactly the right time for that leg, fails to see it, starts to panic after another minute or two, then sails on into the unknown, becoming increasingly stressed as the seconds go by. It's one thing having an instructor there to "rescue" the situation - another when the student is flying solo and "fear of failure" is blinding the student to the big navigational picture. I find the student often subsequently blames his/her technique, presuming they are off track, rather than their failure to look around and confirm position in an increasingly stressful situation.
To help rectify this I fly dual with the student on some longish legs (say 30-40nm), ideally in uncrowded/uncontrolled airspace, wherein the end waypoint is very hard to miss - unmistakeable towns, lakes, or "catching features" etc. I get him/her to set course initially from overhead a point close to, but not at the departure airfield, and to fly the leg(s) as precisely as possible with compass/DI and watch, accounting for forecast winds. En route I have the student pay regular, brief attention to those basic instruments, while mostly maintaining a good look out for aircraft, but NOT to pay attention to ground features until within a few minutes of the end of the leg with its readily indentifiable checkpoint. Invariably, of course, we fly right over it, at precisely the right time.
This excercise, repeated a few times, becomes a real confidence-builder for the student in the basic procedure of watch/map/ground, and as their stress level reduces they become delighted how often the chart now "aligns itself" with the real world!! Secure in the knowledge of how accurately they can navigate by DR alone, their abilities are enhanced further by the addtional techniques mentioned in previous posts.
[ 15 January 2002: Message edited by: buzzfly ]</p>
I find that navigational problems with students often come down to a personal lack of confidence, rather than a deficiency in his/her technique. From time to time I've sat quietly while a student flies bang over the correct checkpoint at exactly the right time for that leg, fails to see it, starts to panic after another minute or two, then sails on into the unknown, becoming increasingly stressed as the seconds go by. It's one thing having an instructor there to "rescue" the situation - another when the student is flying solo and "fear of failure" is blinding the student to the big navigational picture. I find the student often subsequently blames his/her technique, presuming they are off track, rather than their failure to look around and confirm position in an increasingly stressful situation.
To help rectify this I fly dual with the student on some longish legs (say 30-40nm), ideally in uncrowded/uncontrolled airspace, wherein the end waypoint is very hard to miss - unmistakeable towns, lakes, or "catching features" etc. I get him/her to set course initially from overhead a point close to, but not at the departure airfield, and to fly the leg(s) as precisely as possible with compass/DI and watch, accounting for forecast winds. En route I have the student pay regular, brief attention to those basic instruments, while mostly maintaining a good look out for aircraft, but NOT to pay attention to ground features until within a few minutes of the end of the leg with its readily indentifiable checkpoint. Invariably, of course, we fly right over it, at precisely the right time.
This excercise, repeated a few times, becomes a real confidence-builder for the student in the basic procedure of watch/map/ground, and as their stress level reduces they become delighted how often the chart now "aligns itself" with the real world!! Secure in the knowledge of how accurately they can navigate by DR alone, their abilities are enhanced further by the addtional techniques mentioned in previous posts.
[ 15 January 2002: Message edited by: buzzfly ]</p>