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one in sixty rule


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I suppose I should have explained but I did say to keep round figures.

 

Anyone tried holding .66 degrees on a compass on a windy day?

 

Frank. .

 

 

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I didn't round the .66 until I added it to the 2 degrees to parallel, that's how I got 3 and not 2.66. I would neither try nor recommend reading .66 of the sort of compasses we use.

 

 

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Little degrees now make big degrees (and Nm) later

That's why instead of using the whole 90nm to get back on track I would use a checkpoint 10,12 or maybe 15 nm down the track, that way once back on track I would still have my original checkpoints to monitor my progress

 

 

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Hi Guys

 

Would it not be easier in flight (again using KISS theory & in easiness of holding heading) to to make a heading adjustment of 4 degrees to the left of original heading of 010 onto 006, fly on that heading of 006 for 30 miles at that stage should by rights be intersecting or very close to FPT. Once planned track intersected fly heading of 008 which by rights should keep all on FPT for remaining 60nm ???

 

Ha Ha tell me to pull my head in if not good response, am just about to have RA Aus cert signed hopefully tomoz arvo. Have done one Nav excercise from Moruya to Temora for Natfly couple of weeks ago (AWSOME !!!, has taken a bit of study and lots of simple calculations in head after trip to get head around a little). I very much have the bit between my teeth to get into as much navigation as can do over next period of time, looking very much forward to beginning to explore our beautifull country some more.

 

Cheers

 

Dave

 

 

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Guest davidh10

Ok. So apart from teaching how to use 1 in 60 or solving the exam question, where does anyone actually use it in VFR flight?

 

As others have said; If you know where you are and can see where you ought to be, then just alter track to converge. The angle doesn't matter much, except that if you are way off track an acute angle will use more fuel than necessary. If you are visual, you shouldn't be way off track.

 

If you are flying over featureless terrain and there isn't at least:-

 

  • One recognisable feature on or close to track, or;
     
     
  • Two recognisable distant features at angles that allow you to mentally triangulate your position.
     
     

 

 

At least once every 30 minutes, then you would not be VFR. Since you cannot tell whether you are on or off track, 1 in 60 is no use.

 

The scenario I can conceive:

 

If you were above BKN and relying on recognising ground features through the gaps, you'd want to be checking ground features as often as possible, as being off-track more than the gap in the cloud may mean you don't know where you are. In that case, you have to go down and have a look around. Once you establish how far off track you are, and go back up above BKN and need to adjust heading to get back on track is when 1 in 60 is useful.

 

 

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Ok. So apart from teaching how to use 1 in 60 or solving the exam question, where does anyone actually use it in VFR flight?As others have said; If you know where you are and can see where you ought to be, then just alter track to converge. The angle doesn't matter much, except that if you are way off track an acute angle will use more fuel than necessary. If you are visual, you shouldn't be way off track.

 

Not true David, I did it in a Navex with an Instructor on board. Had to make a turn to a new leg after identifying a checkpoint, and located the hill and lake, but there was another hill and lake beside the first one. I looked under the verandah of a railway station at the name of the unexpected town. Should have trusted my DG.

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Little degrees now make big degrees (and Nm) later

That's why instead of using the whole 90nm to get back on track I would use a checkpoint 10,12 or maybe 15 nm down the track, that way once back on track I would still have my original checkpoints to monitor my progress

 

The argument against that is making two angles on the track uses extra fuel, but the advantage is you're going to see what you were expecting to see much sooner.

 

 

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Thats exactly right Octave.

 

Again even with my lack of navigation experience I would think it to be safest least confusing option to make way back to FPT in a reasonable time/distance so can go back to using pre planned checkpoints on flight plan so to not be spending to much time looking at maps & chasing landmarks confirming new track (how many times have we all heard the words Aviate, Navigate, Communicate) All to easy to find yourself navigating before aviating if not carefull & who wants to fly around continuously crunching numbers in head and dwelling over maps in the cockpit ??? not me thats for sure. I see that with more experience using the 1 in 60 rule would be adiquately acurate to track directly towards chosen destination, however I believe for not so experienced pilot to find track again rather than trying to calculate heading from an of track location poses some risks of missing destination as turboplanner says a small degrees now make big degrees (Nm) later.

 

 

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Thought about it again, a bit more seriously. Frank & octave are right. I hope you are going to send them a cigar Turbo!

Hadn't thought of that, but since you're well off track now and on the way to running out of fuel, how about you get to ask 6 questions at the next meeting with board members?

 

Anyone like to pose another simple question to help Shafs, and now Destiny get some practice?

 

 

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Guest Andys@coffs

Frank was spot on, I can remeber getting my A$$ kicked allover the sky with turbulence in a trike and wondering if the heading i was holding (perhaps trying to hold is more accurate) was within 10degrees of intended. Anyway got around the nav course and then I noticed when I got home that the compass attached to the forward post wasnt actually aligned front to back with the aircraft front to back, off by 5 degree or so and there was wind aloft on the day....

 

Bottom line is that it was map reading and understanding where I was almost all of the time that got me around the course, not tootling along and suddenly at 30 or 60nm from last check point going OMG Im Xnm suddenly off track........

 

That said, anyone whose done some inland flying will recognise that if you dont fly IFR (being roads, railways and rivers.....and rivers aint that much use cause their either non existant or 20km wide of late!!!) then you'll be needing to use it cause absolute fixes arent as common or close together as they are in the more populous parts of Australia

 

Andy

 

 

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If you are flying along and the landmarks have stopped, and you see one you recognise and you know how may Nm you've travelled, that's where you would use the 1 in 60 rule.

 

If you can see landmarks along your track, you shouldn't have drifted off anyway, but if you do, of course you can see where to go --- but we're not talking about that, we're talking about using the 1 in 60 where it works, and trying to give Shafs simple examples.

 

BTW the GPS is switched off or has had a terminal failure.

 

 

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While it`s true that the answer to Turbos question is in fact less than 3 degrees, I`ve yet to see an example or exam, where anything but the nearest round figure has been used!

 

In my opinion, the question is theoretical and it`s simply about knowing how to apply the 1:60 principal.

 

In reality, unless the pilot is extremely skillfull , using the 1:60 is at best difficult, by the time the calcuations are done, the aircraft is furthur down the Track Made Good and the faster the AC the furthur along, therefore, the calculations would be incorrect, in any case.

 

In the AC we fly, I want to meet and shake the hand of the pilot who can hold a steady compass heading over 90 nm and be perfectly on target at destination.

 

Frank.

 

 

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No problems dex. Glad to help.

 

As others have illuded to it is much simpler to regain the track than to calculate the closing angle to the destination.

 

The only problem with that is if you have covered more ground than is left to the destination, so a closing angle is required.

 

But generally just regaining track and holding the NEW heading is a better idea in my opinion.

 

There's a few reasons for this.

 

Your flight planned track is there for a reason. You may have picked that track due to better country for a forced landing, high terrain, cta steps etc.

 

Also your markers will still be on the fpt, working on a closing angle track you may need to do these again.

 

The 1 in 60 also helps alot after a diversion. If you divert, instead of getting the whiz wheel out and replotting for wind, you just expect drift downwind. Wait a few minutes and do a 1 in 60, this gives you your wind adjusted heading.

 

 

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Just a thought.... not about the 1:60 though, but just something I've noticed from reading through... Remember to not chase the compass... just thought I'd put that out there as when you're in turbulent conditions you end up a mess if you do that. Get your heading at the start sorted, look ahead at an aiming point and head in that direction. Obviously not such an issue in larger aircraft, with DG's etc... but in a trike or drifter when you can be knocked around like a tumbler, you navigate by compass, aiming point, compass aiming point...

 

Just my thoughts.

 

 

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I dont concider 1 mile left or right of track to be off track.

 

For those of you who dont know I'm dislexic I can not do numbers in my head, I fly by site alone.

 

So the 1 in 60 rule dont work for me.

 

Bernie.

 

 

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Guest davidh10
I dont concider 1 mile left or right of track to be off track....

Ordinarily, No, but to realise that you are is important. It may be the difference between flying past or penetrating restricted or controlled airspace.

A "track" is like a budget. It is a plan. You can deviate from your plan as long as you realise you are doing so.

 

On one of my navs, I picked up mid leg, from landmarks, that I had drifted about 2 miles off track and indicated to the CFI that I would change heading to intersect the planned track. His response was. "You can see your next waypoint, so there is no need."

 

 

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Things that you can calculate readily on the ground become confusing in flight. You have other things to do, as well. I worked out something many years ago , that I would rather be roughly right than PRECISELY wrong. Don't worry too much about rounding a few numbers off. It's the percentage error that matters. You don't (and can't) fly a small plane except in the calmest of conditions, to a degree or even three., on HEADING. on the crook magnetic compasses that we have..Most planes drift to one way ot the other. They have a tendency to TURN. , and in rougher air they wander all over the place. You have to fly an average..If you find that you have been holding a heading to the left (smaller numbers as Motz says) make a conscious effort to go to the right for a while. Try to make it even out.

 

Generally it is better to get back on the flight planned track ( and the better you have planned the more benefit being ON track). You don't lnow exactly when you are back on track UNLESS there is a positive fix near it so maybe aim for a very identifiable point on track. At this time, it may not be visible. Whether you like it or not, all you will have is your calculations and the ability to hold an AVERAGE heading IF you can't identify a fix (pinpoint to some) with ABSOLUTE certainty, then it is not much use. The mind tends to make something into what you want it to be in these circumstances. You say to yourself ..that MUST be Bugtown or whatever because you WANT it to be.

 

Anyhow getting back to the original question, It's probably the realm of an exam situation, or in the past when you might have a full time navigator taking shots of stars or the sun , with a sextant, when you get a gap in the clouds. ( Been there believe it or not). there is a bit of applicability, but not a lot to our ops.( My view )..

 

Holding a compass COURSE does have value. I did say course deliberately, and NOT heading. You must be able to do this unless you can see identifiable and known places all around you. Plenty of places in australia where that does not happen at all.

 

IF you find, having done a fair job of flying a compass course that you do have a track error of "x" degrees, then changing your course by "x" degrees Towards your planned track will parallel it and you then won't get further off course. IF you turn "2 x" degrees you will regain it in the same time or distance that it took you to get off course... Nev..

 

 

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does anyone have any tip on getting my head around the one in sixty rule.Paul

I suggest you buy a Nav-Aid Rule and forget about trying to do calculations , flying and navigating at the one time.

 

Takes all the work out of track corections and diversions.

 

Joe

 

 

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