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Old 20th Aug 2018, 13:26
  #9 (permalink)  
wiggy
 
Join Date: Feb 2001
Location: The Winchester
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Do you have an HSI or similar?

If so a million years ago during basic’ish military IF teaching we used to teach a technique for point to point/fix to fix using it - I’ll have a go at explaining the method but you’ll need to be gentle with me here....

It works by visualising the HSI as a virtual” MAP” with the VOR at the centre, your position along the tail of the VOR needle and your “go to fix” positioned somewhere along it’s relevant radial out from the centre of the HSI.

Now the slightly tricky bit - The distances you visualise out from the centre of the HSI to “plot” a picture depend on your range and the fix range from the VOR...e.g. if you are at 60 miles and the fix is at 30 then you “draw” yourself at the tail of the needle (at the circumference of the dial) and the fix half way out towards the circumference along it’s radial.

If OTOH you were at 30 DME and the fix at 60 DME then “draw” it the other way around - you picture yourself half way out from the centre, with the fix along it’s radial at the circumference...the idea is to keep both fixes “on” the HSI, the bigger DME needs to be the one you are imagining as on the circumference.....still with me?

Finally, almost... mentally “draw” a line between the two points....mentally drag that line back to the centre of the HSI and bingo, where that imagined line crosses the compass rose is the track to fly to your “go to fix”..

Try drawing it out using simple numbers for starters to get the hang of it...for instance the fix is on the 060 radial at 40 DME and you are on the 120 at 40DME..etc...

Now as some one will recognise from the above I was never an A1 QFI so I hesitate to go any further in trying to explain it without the use of a whiteboard and four colours....not sure if anyone else recognises the technique, if it is still taught or better still if there’s anything online like a handy video that covers it...

It sounds horrid until you get the hang of it but it actually works very well and was actually a very very useful technique for some niche (military) applications in “free” airspace. In the modern real world of controlled airspace trying to comply with ATC I’d commend all the earlier advice about vectors, etc.

Last edited by wiggy; 20th Aug 2018 at 13:37.
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