Runway thresholds not 180 degrees reciprocal
Runway thresholds not 180 degrees reciprocal
Sorry, slow evening!
I seem to remember a story of a long runway where, due to magnetic variation changes between the two thresholds, there was 190 degrees (and 170 degrees) between the allocated alignments.
Do I remember wrong? If not, is there just one or are there actually a few?
I suppose another option is if any bendy runways out there? I've landed on some bendy grass strips, but nothing in concrete (yet).
Have a nice evening! Sam.
I seem to remember a story of a long runway where, due to magnetic variation changes between the two thresholds, there was 190 degrees (and 170 degrees) between the allocated alignments.
Do I remember wrong? If not, is there just one or are there actually a few?
I suppose another option is if any bendy runways out there? I've landed on some bendy grass strips, but nothing in concrete (yet).
Have a nice evening! Sam.
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Never heard of a hard runway being different like that. They do change however as the mag var changes. Ours was 21/03 until a couple of years ago, it's now 20/02.
Last edited by thing; 28th Aug 2013 at 19:17.
There used to be one in the west midlands possibly Defford? I was told the ground survey gave different readings at each end so they had to designate the reciprocals slightly different.
Last edited by chevvron; 29th Aug 2013 at 09:22.
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On an east-west oriented runway the runway orientation will always be slightly different at each end due to the effects of convergence. Check out any example from the AIP, e.g. Heathrow 09L/27R:
09L: 089.67 Degrees True
27R: 269.71 Degrees True
Not a lot in I grant you but it'll always be the case - and more evident the longer the runway is.
NS
09L: 089.67 Degrees True
27R: 269.71 Degrees True
Not a lot in I grant you but it'll always be the case - and more evident the longer the runway is.
NS
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An immature and unrealistic part of me wants to see a runway centred on magnetic north pole with the orientation listed with reference to magnetic north. "Do you want 36 or 36 for departure, if you can accept departure from the intersection, 18 is available."
After our trip to the geographic north pole in April, I can confirm that getting home from there is uncomfortable for the first 5 miles (as everywhere is 180 degrees! It is only as you move away that you actually get a useable indication!
For the original question, if I remember right it's a hard (long) runway somewhere in Alaska/Canada where it gets a large enough variation between the two thresholds to tip the balance into an non-reciprocal bearing. Think something like (example only) 274.9 degrees (RWY27) and 095.1 degrees (RWY10).
'later, Sam.
For the original question, if I remember right it's a hard (long) runway somewhere in Alaska/Canada where it gets a large enough variation between the two thresholds to tip the balance into an non-reciprocal bearing. Think something like (example only) 274.9 degrees (RWY27) and 095.1 degrees (RWY10).
'later, Sam.
