Low / High Altitude Airways

[Guest allblack]

Hello.Can someone please tell me what the difference is between the Low and High Altitude Airways, also the difference between how MSFS uses them, and how they work in real life ( I presume the two are different!! ).I plotted a course between EBBR and KSFO, and the difference in the route taken between the Low and High was quite significant. High altitude airways added about 400 nm to the trip, and I can't imagine airlines would jump at this opportunity.Which should I use in MSFS, when and why? I've checked in the 'Help' database, but couldn't see anything there.Thanks y'all,allblackPS: Glad to be waaay down here in New Zealand at the mo'....

[someone 0]

Simply put, Low altitude airways, called victor airways, are airways below 18,000 ft. High altitude airways, called jet route, are above 18,000 ft. Thats how it is in the US, I don't know about the rest of the world, I've never flown there.

[Guest Jet]

So if you file for a flight plan at say FL190, you should be on a J-Route versus a V-Route??I have been doing my plans on FS2002 and note that I get assigned V-Routes even when filing above FL180.What should I be doing if I was in the real world?Thanks.

[Guest RonB49]

From my experience, FS2002 has done well on assigning me V-routes below FL180 and J-routes above. Sometimes V-routes and J-route run to and from the same VORs (just at different altitudes. Another interesting info-bit is the fact that all VORs are not created equal. High altitude VORs are designed for the Jet routes and transmit at apower which can give them a range of about 200 Nm. Low altitude VORs are designe for use on the V-airways and have a range of 50 - 60 Nm. Terminal VORs are usually at individual airports and may have less range, yet. FS2002 modles these VOR-types pretty well. R-

[Guest lawyerpilot]

Just remember that you can't be on 18,000. So an IFR flight plan to the West would be 20,000. And to the east would be 19,000.You also have to be aware of MEA's along the route. If you need 1000-2000 feet clearance over something (like mountains), then it's possible that 21,000 would be your min high enroute altitude for an easterly direction. P4 1.8768 ram 80 gig hardriveVisiontek Ti4 4600CH yoke/pedalsElite Multi quadrant19" inch monitor-Soundblaster PCI 512Win XPInstrument rated ASEL -215 hoursAOPALawyerPilots Bar Association"Men without dreams are never free, twas thus this way and thus will ever be."

[Guest CYOW_pilot]

allblack,(ref your handle, I used to play a lot of rugby back in my high school days :-])I have quite a bit of real world experience flight planning around N America, the North Atlantic and Europe. Anyway, as mentioned below, the only real difference is the altitude that is used to fly that airway. In North America the dividing point is 18000 ft / FL180, in Europe is varies from country to country but is generally up around FL240.In the end it really doesn't matter except how you fill out the flight plan. If the route you want (min time route)between two points is not joined by a high level airway but a rather by a low level airway then just file direct between the two points (rather than the low level airway) if you want to fly in the high level airspace. North America is far more flexible in the possible routings than Europe is.For your example route, the entire route would never be flow just by airways (high or low) (and don't use the FS2K flight planner, its logic seems pretty fuzzy to me).A route from Brussels to San Fran would depart European domestic airspace on high level airways then once NW of the UK transition either to a NAT track or direct routing between 10 deg longitudinally spaced lat/long points (for that route likely up near 60N to 65N eg, 62N20W 64N30W 66N40W 66N50W etc). From there it would transition to the Northern Control Area or NCA tracks (eg. NCA B, NCA C) across northern Canada down into central Canada and then into the high level airway or navaid/waypoint direct routing structure as required until it got to an entry point for the STAR serving SFO arrivals from the northeast.Kevin in CYOW