Cutting Corners at VORs

[UGAflyer]

just turn when the 430 or 530 tells you to...

 

[avbug]

Start your turn a mile and a half or so early most of the time, you'll be fine. If you don't have DME, then you should be timing your progress. You'll not the CDI getting more sensitive.

If you have absolutely no idea where you are, then wait for station passage or for the needle to begin getting erratic as you approach the cone of confusion, and make your turn. Then do something to ensure that you're not so lost next time. You should know where you are, all the time. DME or not.

 

[PropsForward]

just turn when the 430 or 530 tells you to...

Yeah, them 430's sure are nice.

 

[Flylo]

What did your instructor tell you? He should tell you to look it up from an official source, not here. Start studying the AIM. To make it easy, try 5-3-5. Waiting for station passage may be OK in a 100 kt ground speed trainor, but not in a faster aircraft or strong tail wind.

Thank all of you for the answers you gave.

I read 5-3-5 in the AIM and 14 CFR 91.181 and have decided that "Full Flaps", my instructor, was probably right when he said I could cut the corner at 4 NM from the VOR.

The question I asked came up because of a route I was flying on a simulator and I may not have made it perfectly clear what I wanted to know.

I took off from a small airport and was told to fly direct to a nearby VOR climbing to 4000', intercept an airway radial there and fly that radial to the next intersection.

For the sake of clarity lets say the I was flying a heading of 360* to the VOR (180* radial) and, the airway I'm going fly when leaving the VOR is the 280* radial. So, in effect, I'm making a hard left turn.

The reason I asked the question is because: I'm CHEAP!! I didn't see any reason to be paying for that high dollar simulator (or a real airplane for that matter) when I know I'm just going to the VOR and then coming right back to darn near the same place, so I asked how close I was legaly "required" to get before I could turn (the simulator does have DME)? Based upon the answers I've read here and not finding anything that specifically says otherwise in the regs; I don't believe anyone is going to give me any trouble if I make the turn 4 NM (the edge of the airway) from the VOR, unless I was very close to my destination airport and involved in an ATC directed traffic pattern or arrival procedure.

It's nice to know that "Full Flaps" has some idea of what he's talking about but it never hurts to check.

Thanks again.

.

 

[A Squared]

I don't believe anyone is going to give me any trouble if I make the turn 4 NM (the edge of the airway) from the VOR, unless I was very close to my destination airport and involved in an ATC directed traffic pattern or arrival procedure.

Uhhhh, I wouldn't say that. Yes, there is some tolerance, and it is good to have an idea of what that tolerance is....but, you should never be intending to use that tolerence. Operationally, it is hard to defend doing anything but your best attempt to remain on the centerline of where you should be. If you are cleared on an airway, you should be on the centerline, if you're not on the centerline, you should be correcting back. If you're cleared on a radial, you should be making your best attempt to fly that radial. Sure, leading the turn a little to intercept is fine. leading the turn to intercept the edge of the airspace. Uh,uh, particularly in the terminal environment, 4 miles might raise some eyebrows, or even cause problems for ATC

 

[TonyC]

Like A Squared said, it is proper to turn before sation passage in an effort to fly from centerline to centerline. Turning earlier than that because you know there is a tolerance or width is improper.


In the example you specified, you arrive at station XYZ on a 360 course, and you plan to depart the station on the 280 course -- an 80 degree left turn. It is proper to begin the turn approximately one turn radius' distance prior to reaching the station. If your groundspeed is 120 Kts, and you use the 1% of groundspeed method to determine turn radius, you should begin the turn approximately 1.2NM prior to reaching the station - - not 4.


Your goal should be centerline.

 

[crudeoilpilot]

Did we make a turn

Tony; you did mean to say the 280 course I'm guessing. You're right, the groundspeed trick works perfect. A 90 degree turn at 250 kts, start at 2.5 miles etc. to fine tune it take your 90 degree window in your HSI and divide it into 3 sections, if you have a 60 degree turn at your 250 kts use 1.8 miles, a 30 degree use .8. Leading early for passenger comfort or should I say less drink spillage is easy to accomodate with this rule.

 

[TonyC]

Tony; you did mean to say the 280 course I'm guessing.

Why, of course that's what I meant! My eyes were too blurry to notice the error; thanks for the help!

Next stop, the EDIT button!

 

[coonass one]

The way I do it:

No matter what altitude, at 4 nm prior (corrected for slant error on the dme) I set up a 20-30 degree intercept, and just wait a few seconds. Works out well most of the time(depending on speed of course).

 

[philo beddoe]

I use 1% of GS minus .5 nm, which works well for me. But then again, I tend to roll into turns with a fair amount of enthusiasm. This rule works pretty good with arcs as well, since it is better to be a tiny bit late turning onto the arc than be too early. Which brings up another point: why does every one teach a 90 degree turn onto the arc? Since you are going to join further along the arc as you turn, an 80 degree turn works better, since you will not have to immediately turn again just to maintain the arc.