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In a short hop, how to know which FL?

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Hi allLets say a short hop from EBBR-EGLL, what would be the optimum FL?Of course with the little fuel needed for this short flight, the optimum FL would be something like FL370.But this would be stupid because when you get to that level, you'll already have to descent.So is there are a rule for those flights as to be at a FL for a certain amount of time?Thanks!

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The max FL at this route is 240 in IFR rulesIn VFR the max cealing is 2000 ftIn Europe all westboud flights (in France Northbound) uses an even flightlevel up to fl 280all Eastbound flights (in France Southbound) uses an uneven flightlevel up to fl 290Going higher then 290 the seperation between the flightlevels becomes 2000 ftSeverall sites are dealing with this issues like AIP and AISThe IVAO site contains a lot of links like RouteFinderVATsim uses vroute. Both are free but needs registrationI recommend vroute to find out all of routes and flihtlevels

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I guess this isn't possible with FsCommander? As this program always selects 360 as standard...Will check out vroute in the meanwhile, thanks!

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Hi.Simplest to let the despatcher do his job...I think, if you want to do it the old fashioned way you'll need first to develop a fuel-consumption profile for your plane:For 3 phases (climb, cruise & descent) you have to establish how much fuel is burnt per mile (or per hour) at each airspeed (or ground speed), at each vertical speed, and at each altitude (the equation's not a straight line). Having found the optimum combination for each phase, develop three equations relating fuel burnt to altitude (or FL), VS and airspeed. You'll then need to apply a little basic calculus to find the altitude that gives the minimum fuel use for your planned distance.Once that's all going smoothly you can expand to include step climbs, go-arounds, alternatives at a different FL, winds et c.When you've done all that, rework it into a spreadsheet or gauge and upload it to save me the trouble, lol. I was going to do it once, a long time ago, but got bored while still doing the fuel profile test flights. Now I just guess, based on past performance.I suspect various flight management computers will do the job for you too.It's a shame it's not simpler!D

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I usually use Flightaware to get an idea of proper flight levels and flight plans, it seems FL220 is what's mostly used on this route.

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So is there are a rule for those flights as to be at a FL for a certain amount of time?
Rule of thumb:For flights shorter then 280nm: Distance = FLFor example EHAM-EGLL is 200nm -> FL200

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Well Dave, your solution will be the best, but I guess I gotta go with Egbert :D.Thanks for the explanation though, still amazes me how much work fuel planning can be...

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I usually use Flightaware to get an idea of proper flight levels and flight plans, it seems FL220 is what's mostly used on this route.
This is what I do for North American flights (I'm in the US). My VA uses all real world flight schedules for over 900 airlines world wide, and a GA division, so I never fly anything but a scheduled carrier. You can check it out here:<< http://www.air-source.us/Default.asp >>

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If you look at the distance, and your intended rate of climb, you can work out how many miles you will cover to get to a certain altitude. Same for descent. If you are limited in hight, then that will be your cruise altitude, if it can be reached before a descent is needed.

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On route segments where aircraft are flying both short hop and long haul flights, ATC will some times cap the altitude of the shorter hop routes to keep them out of the way of the long haul aircraft. This reduces congestion in the higher strata allowing better efficiency for the long haulers.For aircraft performance efficiency a parabolic vertical profile is desired in most cases that being a close TOC and TOD if maintainable. That is because up until rated performance ceiling higher altitudes provide better performance efficiency.As suggested you can input your route into an FMC if so equipped to 'test' the route for optimum cruise altitude before filing. I use FSBuild which as many aircraft profiles and a link to Active Sky winds aloft data. To determine the max altitude I input an extremely high cruise altitude along with the route and aircraft type for the first run to see where TOC and TOD fall near each other to get the max altitude. I then rebuild with a practical altitude.If you have access to real world flights you can see what has been filed. For flights entering and/or leaving US airports flightaware.com has scheduled and actual flight data showing the filed cruise and actual cruise. You can also get the track log showing altitudes and ATC facilities used at a number of coordinates along the route.

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+1 on Egbert Drenth this is what most people use.redevisser's info is not correct. In Europe, and most of the World, the airspace above FL290 up to and including FL410 is called RVSM (reduced vertical separation minimum) where aircraft are separated by 1000 ft (used to be 2000 ft about a decade ago). Above FL410 its 2000 ft separation. eg. FL430 westbound, FL450 eastbound, FL470 westbound, and so on.

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