Route Planning for Weather & Fuel

[Ted Johns]

Originally Posted by JimP

In interesting Operations problem here.

Factoring out weather, take distance, fuel consumption rate, average speed, and fuel cost to optimize the route for lowest cost.

This would be a variation on the "traveling salesman problem", a problem in route optimization. This is a hard problem to solve. As in NP-hard (Nondeterministic Polynomial-time hard).

There are sophisticated algorithms that can solve for this problem, I'd be a bit surprised if AirNav is using them. On the other hand, maybe this is why AirNav is super slow sometimes, the servers are buried running optimizations.

See http://en.wikipedia.org/wiki/Travell...lesman_problem

Just FYI: There is a related problem in theoretical computer science (the P=NP problem) that qualifies for the Millennium Prize. You could really outfit your RV10 with that extra million!

[TShort]

Originally Posted by Ted Johns

See http://en.wikipedia.org/wiki/Travell...lesman_problem

Now my head is spinning...

How do those guys that hit all the airports in a particular state in one day figure the route? Just sit down with the chart or is there some computer optimization process?

T.

[Ted Johns]

I just did the math. Using the optimum algorithm (that I know of), the time to solve the route problem exactly is (n^2) x (2^n) operations, where n is the number of airports to solve for.

Using 10 airports, the solution time is 3ms. No sweat. Done before your finger leaves the enter key.

Using 100 airports, the solution time is approx 10^19 years. As in, more than a trillion trillion years.

Assumptions: 3Gig pentium. (It really doesn't matter!)

Doug, I hope this wasn't too far afield from RV stuff...

[erich weaver]

I thought from Dan's original post that I could go to the Airnav sight and generate a graphic similar to the one he posted - a route map with waypoints posted, but I couldnt seem to find such a feature. DId I miss something on their site, or is the graphic produced from some other software? Would like to check it out - it has a nice look to it.

erich

[dan]

Originally Posted by erich weaver

I thought from Dan's original post that I could go to the Airnav sight and generate a graphic similar to the one he posted - a route map with waypoints posted, but I couldnt seem to find such a feature. DId I miss something on their site, or is the graphic produced from some other software? Would like to check it out - it has a nice look to it.

erich

It's something I did by hand. If Paulo Santos would return my emails, we'd have something exactly like this on AirNav/Weathermeister. But he's apparently too busy to return emails.

It was worth my effort to produce this "kneeboard fuel price chart," because today my original plan today was to head to EGE. Almost as soon as I took off, the forecast for the Denver area didn't look so hot. I turned left and changed my plan to U42. Then when I had a ton of fuel remaining I pressed on to BPI. There was no guesswork since I had done all the planning up front. Well worth the hour or two I spent on this.

Such a simple concept. Why haven't I seen this done before? I've done it textually many times, just not a map of it. The map is the way to go.

[ohiopilot]

Good luck getting any type of response back from AirNav. If you do, you are "the man".



(I've tried many times for different reasons.)