Max distance between GPS waypoints?

Morgan3820

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400 nm trip. Filing IFR. Straight shot between departure and destination airport. Previously, I would find some VOR’s as GPS waypoints for just in case. but this time not many VOR’s are presenting themselves in a convenient way. The fight is not over congested airspace. ENC, VA, WV, OH. Could get direct routing over 400nm? Is there a rule that addresses this situation?
 
I don’t know of any reason why you cannot file direct. ATC will let you know if they need something different.
 
in the spirit of the interweb, I'll offer a response that is probably out-of-date.

At one time, you wouldn't get a direct routing unless your were in radar coverage the entire way (didn't matter what equipment you had). This didn't apply to oceanic flights.
 
I don’t know of any reason why you cannot file direct. ATC will let you know if they need something different.

AIM 5-1-6d2 has details of what you're "supposed" to do when filing RNAV routes. But few ever do, and I'm certainly not losing sleep over it.
 
AIM 5-1-8 d. 2. (f)

"File a minimum of one route description waypoint for each ARTCC through whose area the random route will be flown."

I'm not sure if anyone actually does this.
 
Automation doesn't care. File direct. If there is an adapted route required, ERAM will apply it and you will get an amended route.
 
Seems lots of people don't care, but maybe you do. As mentioned, AIM 5-1-8(d):

Highlights...
...begin and end over appropriate arrival and departure transition fixes...
...minimum of one route description waypoint for each ARTCC...
...avoid prohibited and restricted airspace by 3NM...
 
When I flew with one of the first Mode S transponders, ATC thought I was some kind of special mission and they were unusually helpful as I flew VFR/IFR across half of the USA.

My route of flight was from Central Texas to Northern Missouri, GPS direct. With only the destination as a waypoint, all I did was make slight heading corrections all the way there.
 
AIM 5-1-8 d. 2. (f)

"File a minimum of one route description waypoint for each ARTCC through whose area the random route will be flown."

I'm not sure if anyone actually does this.
I do. I heard somewhere (probably the "opposing bases" podcast) that they find it helpful to have a fix in their airspace, as they often have no idea where your destination is. Remember they don't have your magenta line to tell them where you're going. They know where you are, and are familiar with fixes & airports in their sector, so that gives them a better handle on direction of travel.

Generally speaking though there just isn't enough traffic at piston altitudes for it to matter much. Plus we're relatively slow and easy to deconflict.
 
Going from Central FL (KSFB) to Chattanooga, I had leaned to never file direct as it put me right over downtown Atlanta. So, I would file to a waypoint either to the East or West, outside the Bravo. On more than one occasion, I was offered "direct destination'. I declined after trying it just one time. That one time I accepted it, I got all the way to the Bravo, then was turned me to the east and I kept getting vectors around the outside ring. It took me longer than my original plan.

Over the years, I have used direct but I have also learned that it's better to plot some points to avoid specific restricted areas (and the Atlanta Bravo). Usually, it does not add more than 1 or 2 minutes to a 3+ hour flight. Then, it is easy to delete waypoints in the 430W when offered direct. Adding waypoints take more time.

Also, there may be 'rules' for your home airport. I knew them for KSFB, but now that I have moved to KBOW, I am in "discovery mode". It seems they always want me to plot LAL as either an initial or a final point. They also have specific waypoints to the northeast and southeast of Zephyrhills to avoid the jump zone they seem to always give me. I just put them in the flight plan now from the start.
 
I file Direct pretty much all the time, even when I know there may be a predictable reroute. Flying from my home ‘drome near Austin I know it won’t stick and I pretty much know the reroute but I do it anyway (and I check FlightAware or 1-800 before starting up, to see the re-route and load it). But leaving a gas stop at a small field in the middle of the country to another gas stop at a small field in the middle of the country, I file and get Direct virtually all the time.

The one exception is if I’m crossing Houston’s Bravo. I’ll specifically file V306 at or above 6000 because they’ll let me do that; otherwise they route me around the Bravo (I actually learned that by calling Houston Approach and chatting with them about options).

And if I know I can probably go Direct without a reroute I’ll typically pick up my clearance in the air, weather permitting, since all the controller needs to do is say “Cleared Direct, climb and maintain X”. If I know a reroute is coming I’ll often call from the ground, just to lighten their load.
 
The following Say Again? article by Don Brown discusses this recommendation from the AIM and the reasons why it's a good idea.

https://www.avweb.com/features/say-again-39-atc-205-ifr-flight-plan-ii/

Notice how he uses radial/distance fixes ( i.e. HMV180020 ) when there isn't a convenient NAVAID or fix close to the desired direct route.

I agree with Mr. Brown's guidance, at that time, however with the newer system (ERAM) it is no longer necessary.

As for the magenta line, enroute controllers have a route display that (hopefully) coincides with yours (IIRC it's blue). I don't know if STARS has an equivalent function for terminal controllers.
 
All enroute facilities have ERAM, and all flight plan processing is done by ERAM and forwarded to terminal facilities. If a terminal controller inputs a flight plan, he/she is interacting with ERAM, which will in turn transmit the necessary data to the STARS (terminal) computer system.
 
I've heard controllers ask a pilot what his direct course would be to some far off destination...the pilot tells the controller what his GPS says as a direct course from present position...and the controller says something like "cleared direct"
 
oh, the other comment I meant to make....
I'll bet it would be easy enough to find some random intersection waypoints that are along a direct route...and file those... don't know if they'd take it though
 
my normal IFR filed route from charlotte nc to lantana fla is JQF -> KCRG -> KLNA, 541nm. sometimes in south fla I get a few reroutes but it's mostly for PBI traffic. I'm sure I could file direct and most likely get it, expecting the same reroutes near PBI.
 
in the spirit of the interweb, I'll offer a response that is probably out-of-date.

At one time, you wouldn't get a direct routing unless your were in radar coverage the entire way (didn't matter what equipment you had). This didn't apply to oceanic flights.
I wonder why not oceanic routes?
 
oh, the other comment I meant to make....
I'll bet it would be easy enough to find some random intersection waypoints that are along a direct route...and file those... don't know if they'd take it though
ERAM should know every published fix in the nation and many outside.
 
Given @PastZTL 's screen name, sounds like he/she knows how things are "really" done based on real world experience.

I agree that the AIM should be updated if the extra effort is not required.
 
Whenever I file a specific route, it’ll usually get changed anyway. Why not just file direct everywhere - they’re just going to automatically reroute you anyway?

This question is not intended to be as snarky as it sounds, but seriously, why not just file direct everywhere and get what you get? If you need something specific, I suppose you could ask for it later, but the times I’ve needed something specific and tried to file it, it’s pretty 50-50 that that’s what I’ll get anyway.
 
Whenever I file a specific route, it’ll usually get changed anyway. Why not just file direct everywhere - they’re just going to automatically reroute you anyway?

This question is not intended to be as snarky as it sounds, but seriously, why not just file direct everywhere and get what you get? If you need something specific, I suppose you could ask for it later, but the times I’ve needed something specific and tried to file it, it’s pretty 50-50 that that’s what I’ll get anyway.

Doesn't really work out west in small pistons due to high MEAs, MOAs, Restricted Areas. I'm in the habit of filing on airways. It's pretty easy these days to see which routes have been previously assigned in the past and therefore what you're likely to get.

I can see how in other parts of the country it's not much of an issue.
 
After talking to a number of ATC folks I just file direct anymore. At least here in the Midwest we get “as filed” more often than not. You might get a question on initial heading. Plus, You will likely get some route updates along the way anyway which would change a well planned route.

I have filed specific routes on occasion like flying through high terrain or when I want to avoid weather. The fantastic ATC folks will just ask if they have a question on my thoughts behind the route.
 
Whenever I file a specific route, it’ll usually get changed anyway. Why not just file direct everywhere - they’re just going to automatically reroute you anyway?
Depends on where you are going. Filing direct to go from New Jersey to Rhode Island will NEVER be approved and you'll get a routing that will challenge your writing skills. I filed what I naively thought would be OK, going VOR to VOR without airways, I got a snaking route that crossed Long Island Sound three times. There you want to find some previously filed routes follow the victor airways that cross JFK and then go to the Northeast.
On the other hand, if you are going in an area with not much there, file direct.
 
I don't always file airways, but when I do, I get "cleared direct" before the first waypoint.
 
It's pretty easy these days to see which routes have been previously assigned in the past and therefore what you're likely to get.
The “problem” here is knowing if those previously-assigned routes were compatible with the altitudes I can fly in my Warrior - unless you can show me a way to distinguish between routes used for turbines vs mere mortals? I’d appreciate knowing that tool if it exists.

Filing direct to go from New Jersey to Rhode Island will NEVER be approved and you'll get a routing that will challenge your writing skills.
If you go on FlightAware shortly before you fire up and look up your tail number, you’ll typically see exactly what they’ll be reading to you. I do that, write it on my knee board, and basically end up just confirming it when they read me the clearance. There are other similar sources. About the only things I need to add are along the lines of “fly runway heading until…” and “radar vectors to…”, plus initial altitude, freq, and squawk.
 
The “problem” here is knowing if those previously-assigned routes were compatible with the altitudes I can fly in my Warrior - unless you can show me a way to distinguish between routes used for turbines vs mere mortals? I’d appreciate knowing that tool if it exists.

A turbine is going to have a jet route, Q routes, arrival/departures restricted to turbines only. I use the plan tool in 1800WXBRIEF.com which shows altitudes.

Below is an example. I "think" Foreflight does the same thing but I'm not a FF user so can't say for sure.

upload_2022-5-3_8-39-28.png

upload_2022-5-3_8-38-20.png
 
A turbine is going to have a jet route, Q routes, arrival/departures restricted to turbines only. I use the plan tool in 1800WXBRIEF.com which shows altitudes.

Below is an example. I "think" Foreflight does the same thing but I'm not a FF user so can't say for sure.

View attachment 106553

View attachment 106552
Garmin pilot also sorts them by type, so it's pretty easy to pick out the pa28's from the pc12's. I presume FF does the same.
 
It's pretty easy these days to see which routes have been previously assigned in the past and therefore what you're likely to get.
I've looked that data up, filed it and then got "cleared as filed". The problem is that as soon as I get near the sector boundary, I get "have a reroute, advise when ready to copy".
 
I've looked that data up, filed it and then got "cleared as filed". The problem is that as soon as I get near the sector boundary, I get "have a reroute, advise when ready to copy".

That seems like a whole different matter. Your initial clearance is what you expected.

My personal preference is to stay on airways. There's redundancy in navigation too in the event of GPS outage.
 
When I've used that tool, no one has ever flown my route IFR, I always get IFR - Recent ATC Assigned (0)
Me too. My hack for that is to find a class C near my departure and destination and use those to look up the route. Nearly always works.
 
Garmin pilot also sorts them by type, so it's pretty easy to pick out the pa28's from the pc12's. I presume FF does the same.
Garmin Pilot on iOS also gives you altitude that the route used.
 
400 nm trip. Filing IFR. Straight shot between departure and destination airport. Previously, I would find some VOR’s as GPS waypoints for just in case. but this time not many VOR’s are presenting themselves in a convenient way. The fight is not over congested airspace. ENC, VA, WV, OH. Could get direct routing over 400nm? Is there a rule that addresses this situation?
884nm is the longest direct route I filed and got. From ARR to LAL. I did get some re-routes in GA for airspace but they were minor. No rule that prevents it for a qualified airplane.
 
That seems like a whole different matter. Your initial clearance is what you expected.
Perhaps, but I'd rather copy a different initial clearance while on the ground than a re-route while in the air.
 
East of the Rockies, the "Direct destination" works really well. West of the Rockies, not so well. We have so much special-use airspace that it's far more likely you'll need to be routed.

On Tuesday, we left Elk City, OK (ELK) for St. Louis Downtown (CPS) with a flight plan that I'd filed as DIRECT and simply got:

"you're cleared to the St. Louis Downtown airport as filed. Climb and maintain 15,000 feet."

One and done. The straight-line distance was something just over 400 miles.
 
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