David Megginson
August 6th 04, 11:59 AM
Roger Halstead wrote:
> Again, in the eastern half of the country I doubt the RADAR coverage
> is much better on airways than off. I do agree that it's good to give
> yourself the most and best possible options.
When I've flown down in the U.S. IFR, Boston Centre has occasionally lost me
on RADAR even at 7,000-9,000 ft over Vermont and New Hampshire (typically
shortly after the handoff from Burlington approach) even on the airways. If
I'm VFR, then I might be a lot lower, and RADAR can be really marginal (the
same applies even in Canada -- at 3,000 ft along the north shore of Georgian
Bay or over Algonquin Park, you're lucky to get RADAR coverage even on the
airways, and that's very close to populated areas).
> On the airway you do have a much better idea of how close you are to
> the obstacles than off. Still, on a trip of any distance the list of
> new towers in the NOTAMs can be staggering.
Agreed -- actually, that's one argument in favour of the airways. Instead
of worrying about 60 new tower NOTAMS, you can just concentrate on the
single one that raises MOCA for an airway segment.
I don't want to look like I'm strident about this, though -- since it's
Usenet, it's easy to back oneself into a corner, and I really don't feel
strongly enough about this issue to do that. Of course I fly off the
airways, both IFR and VFR, and I don't think there's anything wrong with
doing so. This is just an explanation of why I (or someone else) might file
a VFR flight plan on the airways, not an attempt to argue that everyone must
fly airways all the time or else they'll kill themselves, their passengers,
and everyone on the ground in a 200 nm radius.
> My only objection to VFR on the airways is the critical need to
> closely maintain altitude.
I'd say that it's about the same either way -- if you're not on airways,
you're still going to be crossing them all the time, especially in the east.
Flight following is a good idea when VFR on the airways, of course, so
that you'll be talking to the same controller as any IFRs.
In any case, when I'm IFR, I find that the airways are not at all busy at my
preferred altitudes (7,000-10,000 ft MSL) -- the twins are up in the teens,
the jets and turboprops are in the flight levels, and the VFRs are down
below 3,000 ft AGL. Usually, I'm the only aircraft at *any* middle altitude
talking to ATC. The biggest conflicts come near airports, where the higher
traffic is climbing or descending, but in those cases the other traffic is
changing altitude so fast that horizontal separation, not vertical, is the
critical part.
One final bonus of the airways is that they make position reports easier for
other aircraft to understand (in Canada, we make position reports on 126.7
when enroute and not under ATC control). "30 miles east of North Bay" could
put you anywhere in dozens or hundreds of square miles, depending on how
you're estimating distance; "30 miles east of North Bay on V316" tells me
where you are within three or four square miles.
All the best,
David
> Again, in the eastern half of the country I doubt the RADAR coverage
> is much better on airways than off. I do agree that it's good to give
> yourself the most and best possible options.
When I've flown down in the U.S. IFR, Boston Centre has occasionally lost me
on RADAR even at 7,000-9,000 ft over Vermont and New Hampshire (typically
shortly after the handoff from Burlington approach) even on the airways. If
I'm VFR, then I might be a lot lower, and RADAR can be really marginal (the
same applies even in Canada -- at 3,000 ft along the north shore of Georgian
Bay or over Algonquin Park, you're lucky to get RADAR coverage even on the
airways, and that's very close to populated areas).
> On the airway you do have a much better idea of how close you are to
> the obstacles than off. Still, on a trip of any distance the list of
> new towers in the NOTAMs can be staggering.
Agreed -- actually, that's one argument in favour of the airways. Instead
of worrying about 60 new tower NOTAMS, you can just concentrate on the
single one that raises MOCA for an airway segment.
I don't want to look like I'm strident about this, though -- since it's
Usenet, it's easy to back oneself into a corner, and I really don't feel
strongly enough about this issue to do that. Of course I fly off the
airways, both IFR and VFR, and I don't think there's anything wrong with
doing so. This is just an explanation of why I (or someone else) might file
a VFR flight plan on the airways, not an attempt to argue that everyone must
fly airways all the time or else they'll kill themselves, their passengers,
and everyone on the ground in a 200 nm radius.
> My only objection to VFR on the airways is the critical need to
> closely maintain altitude.
I'd say that it's about the same either way -- if you're not on airways,
you're still going to be crossing them all the time, especially in the east.
Flight following is a good idea when VFR on the airways, of course, so
that you'll be talking to the same controller as any IFRs.
In any case, when I'm IFR, I find that the airways are not at all busy at my
preferred altitudes (7,000-10,000 ft MSL) -- the twins are up in the teens,
the jets and turboprops are in the flight levels, and the VFRs are down
below 3,000 ft AGL. Usually, I'm the only aircraft at *any* middle altitude
talking to ATC. The biggest conflicts come near airports, where the higher
traffic is climbing or descending, but in those cases the other traffic is
changing altitude so fast that horizontal separation, not vertical, is the
critical part.
One final bonus of the airways is that they make position reports easier for
other aircraft to understand (in Canada, we make position reports on 126.7
when enroute and not under ATC control). "30 miles east of North Bay" could
put you anywhere in dozens or hundreds of square miles, depending on how
you're estimating distance; "30 miles east of North Bay on V316" tells me
where you are within three or four square miles.
All the best,
David