AVIATIONTOOLBOX: automatic route selection

"Julian Scarfe" wrote in message ...
"Ben Jackson" wrote in message
news:tCmbd.121529$He1.75934@attbi_s01...

I keep meaning to apply Dijkstra's algorithm to airway routing.
The key will be choosing edge costs.

I tried something similar for Western Europe. Thinking aloud... My
algorithm was basically:

a) load the entire airway network as a graph using distances as costs

*** I would modify that to use a combination of distance and MEA as
the cost.
I've found that in my personal flight planning, lower MEAs often
translate into a better flight, even if they involve a bit of a
dogleg.

- Jerry Kaidor ( )

Y'all,
My IFR is usually in the SF Bay Area. I have found that the preferred
routes take me miles out of my way. I have also found that a brief
negotiated change of route suc as direct to a fix that
cuts 30-40 miles off the preferred airways is justified.

Consider IFR to Las Vegas. MEA 16K or above. Even 13K
takes you all the way around Edwards. Negotiated changes work
if known and used.

I would suggest that at some point an indicator on the system would
tell the pilot that it is time to negotiate a change.

Gene Whitt

I always understand better with pictures

This is how I understand how this thingy works.

http://www.v1rotate.com/images/navmap.gif

basically draw 3 boxes and do all the calculations inside within these
boxes. This will limit the fixes to calculate.
Limit area #1 for your origin, area #2 for your destination (allow fixes to
be within these boxes so they can join to airways.)
Limit area #3 for route (Only vor's within airways)

KBWI
EMI
J211
JERES
J211
BUSTR
J211
LEONI
J211
JST
J152
AVERE
KPIT

jeres bustr and leoni could be dropped, since they are on same airways

KBWI
EMI
J211
JST
J152
AVERE
KPIT


Here is another link that might interest or help us within this project.
http://gis.vegcrew.net/cgi-bin/viewc....1&view=markup

Hank

"v1rotate dot com" writes:

basically draw 3 boxes and do all the calculations inside within these
boxes. This will limit the fixes to calculate.

It's not clear to me that these regions can be adequately chosen from the
start (especially for long flights) but it certainly would simplify things.

Limit area #1 for your origin, area #2 for your destination (allow fixes to
be within these boxes so they can join to airways.)

I think these will need to extend well beyond the endpoints. As a worst
case example, consider a trip to an airport just on the other side of a
mountain that is too high to traverse directly.

jeres bustr and leoni could be dropped, since they are on same airways

Dropping seems dangerous. What if one of those dropped waypoints is close
to your destination? Will you pick that up later?

--kyler

Dropping I mean could be dropped from processing, since they are on the
airways db...
No need to process fixes, if they are already in the airways list. They are
still listed, but not processed.
Only start and end of the airways are processed.

Extend as far as needed. (ie 250 miles from centerline... no need to
calculate fixes beyond this unless you wanted to.)

Just wanted to spark up the discussion

Hank