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one in sixty rule


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the simple thing about it is your ability to convert distances to angles (degrees). Usually track errors will appear as so many miles track distance and a track error noted . (say right of track of two miles in a track distance of 30 miles gives 2/30 = 4/60 so you have drifted 4 degrees right of track. IF you alter your heading 4 degrees left you should parallel track. If you turn a bit more left (in this case) you will gradually intercept your original planned track. The rate of closure depends on the amount of extra turn. If the angle was altered by eight degrees total you would recover track in the next 30 miles. (In theory) These are only approximations but do work without to much mental arithmetic. It all depends on fairly accurate heading keeping, and you MUST apply all corrections the right way. Draw some examples out on a bit of paper and it will become obvious. Nev

 

 

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The Facthunter explanation is right to the point (provided, as he says, if you apply the corrections the right way)

 

It's 0rigins are quite interesting.

 

The Egyptians knew the earth was round, were using the degree, and were working on 360 degrees in a circle thousands of years before pythagoras was born.

 

They were able to measure the circumference of the earth, and were using the nautical mile for navigation.

 

The Nautical Mile had been derived from the 360 degrees; each degree equating to 60 Nautical Miles of circumference on the surface of the earth.

 

The Egyptians incorporated a nautical mile into the Great Pyramid where twice the circumference equals 1 nautical mile, allowing precise angular calculations to be incorporated which weren't possible with the Royal Cubit.

 

 

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For the 1 in 60 you only need to know 3 things.

 

1.How far along are you since your last fix (on track)

 

2.How far off course are you

 

3. How long since your last fix (on course)

 

Say Our pilot found himself 2 miles right of track. at say time 28. He can measure the distance from his last fix at say time 24, or knowing the distance between his markers he could just have a guess. I would guess and say its 7 miles. So now he has all the information he needs to get back on course.

 

Step 1. Divide 60 by the distance along course (7 miles). Now this is where we normally loose alot of people. 60 divided by 7?? im not a mathematician. But remember, this is deduced RECKONING. Its not en exact science. Instead of dividing 60 by 7, im just going to round it down to 6. now its easy, 60 divided by 6 is 10. Simple.

 

Now, step 2. Mulitply that number by the distance off course. so, we were 2miles off course, so 10x2= 20. You are 20 degrees off course.

 

Now how is that going to help us?Its important to remember that turning left makes the numbers smaller, turning right makes them bigger.Because we are 20 degrees to the right of our FPT (flight planned track) we need to adjust out heading to the left. If we just adjust our heading by 20 deg’s we will make a new track parallel to our FPT.

 

Our original heading was 078 deg’s. To adjust heading to the left we need to make the numbers smaller, so subtract 20 from 078 which is 058 deg’s. But this will only parallel our track, we want to regain track.To regain track, subtract another 20 deg’s, 058-20 is 038 deg’s. This heading will intercept the FPT. But when??, how will you know you have regained the FPT?..Simple, our old friend the watch. remember the 3 things we needed to know, one of them was how long its been since our last fix, simply fly for that amount of time and you will be back on track. Now there is a trick for players here. What heading are you going to fly once you have the track regained??.. 078 degs will not work, remember this heading got you off course in the first place. You MUST remember to write down the first subtracted heading. In this case it was 058 deg’s. and turn onto that heading to maintain your FPT.

 

Here it is again in point form.

 

Once you have pinpointed your position and it is left or right of FPT:

 

  1. How far along course are you (since last fix)
     
     
  2. How far off course are you
     
     
  3. What time is it
     
     
  4. divide 60 by the distance along course you are (remember round it down or up to simplify)
     
     
  5. once you have this number multiply it by the distance off course
     
     
  6. This gives you the deg’s off course.
     
     
  7. to parallel track adjust heading left or right by the deg’s off course (turn left to make numbers smaller, right to make them bigger)
     
     
  8. to regain track DOUBLE the degrees off course and fly for the same amount of time it took you to realize you were off course.
     
     
  9. Turn onto the first subtracted heading, NOT the original heading.
     
     

 

 

 

 

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The Facthunter explanation is right to the point (provided, as he says, if you apply the corrections the right way)It's 0rigins are quite interesting.

 

The Egyptians knew the earth was round, were using the degree, and were working on 360 degrees in a circle thousands of years before pythagoras was born.

 

They were able to measure the circumference of the earth, and were using the nautical mile for navigation.

 

The Nautical Mile had been derived from the 360 degrees; each degree equating to 60 Nautical Miles of circumference on the surface of the earth.

 

The Egyptians incorporated a nautical mile into the Great Pyramid where twice the circumference equals 1 nautical mile, allowing precise angular calculations to be incorporated which weren't possible with the Royal Cubit.

It's also handy to remember that each minute of latitude traversed is equal to 1 NM. Each minute of longitude traversed is only equal to 1 NM if at the equator.

 

 

 

Map of Earth showing lines of latitude (horizontally) and longitude (vertically), Eckert VI projection; large version (pdf, 3.12MB)

 

kaz

 

 

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I still cant work it out.Bernie

Your trip is 120 Nm

 

Your heading is 010

 

At 30 Nm out from the start you look across at a landmark on your planned route and estimate you are 1 Nm to the right.

 

What does your new heading need to be to intersect your destination?

 

Any navigators who can help Bernie out?

 

(Edited the 60 km out - sorry, I got LOST)

 

 

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Miles....Nauticle Miles.....Kilometres......Take your pick !

 

The 1 in 60 rule is used in air navigation, and states that if a pilot has travelled sixty miles then an error in track of one mile is approximately a 1° error.

 

In navigation, every 1° of track error, and every 60 nautical miles flown, results in the aircraft being 1 nm off track.

 

Frank.

 

 

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How About, a = 60 x d / D, where, a = angle off track, d = distance off track, D = distance travelled (from station or last known fix)

 

so if the distance travelled was 35nm and distance off track was 7nm, then the angle off track is 60 x 7 / 35 = 12 degree's off track

 

And maybe I missed it! did someone explain that the 1 in 60 rule, is of course the rule of thumb! that if you have travelled 60nm and are 1nm off track that you will have a track error of approximately 1 degree. Or to put the other way if you were to travel 60nm 1 degree off track you should find yourself approximately 1nm off track!

 

And yes I see Farri has explained this, Oh Well !

 

 

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Blues head, that's how the books say to do it, and that's why so many people have difficulty with it. That's a pretty looking formula but doing it in the air gets a bit overwhelming for some.

 

K.I.S.S.

 

 

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Absolutely correct Motzi, however in some cases it can be of assistance in understanding what the heck we are attempting to achieve in the cockpit!

 

KISS so why not just look outside and figure we need to be over there and just go! KISS

 

 

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Absolutely correct Motzi, however in some cases it can be of assistance in understanding what the heck we are attempting to achieve in the cockpit!KISS so why not just look outside and figure we need to be over there and just go! KISS

I've often thought this too Blueshed. If you can see you are off track then you know where you should be so just go there!

 

I'm talking about recreational aviation here so let's keep it simple eh?

 

Pud

 

 

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Guys, the poster asked about how to perform a 1 in 60. It's a requirement that you know how to do it if you want a xc endo. Just go there while practical, will not get you a pass in your test.

 

 

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I thought my previous post would give good explanation but can`t access the links!

 

Turbo, What the heck !!!

 

Heading 010, 30 nm out, 1 nm off, 90 nm to go......To keep round figures....007 to make destination.

 

Frank.

 

 

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looks right to me, -2 degrees to parallel and -.66 degrees to converge with destination. Rounds up to -3 degrees therefore 007. If you did not apply a correction (and if nothing else changes) you would miss your destination by 4nm.

 

 

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OK, that's two different headings, so who has it right?

 

For the ones who say, that;s not a lot/you look across and just turn towards your original track, I did that once on a day of poor visibility and low cloud, and in the distance saw the mountain I was tracking for. 20 minutes later discovered it was the wrong mountain.

 

Little degrees now make big degrees (and Nm) later

 

 

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