DME arcs

[A Squared]

There are no feeder routes to the arc. How is one supposed to get to the beginning, assuming no GPS or RNAV unit (I know one in the same).

On the airways. To OTEJE via V191 from the Thief River Falls VOR and the OTAXY on V430 from Devils Lake VOR

 

[CloudyIFR]

What if you're coming down V171 from ROX VOR and 30 miles out you go direct to OTEJE, can you make the approx. 150 degree right turn to the arc?

I just don't see why that if you're at the MEA of 2,900' you just can't stay on the airway to the VOR and intercept the arc. Yep, you'll be 400' high but if you can easily lose that altitude. Also, isn't it safer and more likely to stay within the protected airspace of the arc making a 90 degree turn onto the arc versus 150 degrees? All depends on the gruondspeed.

Also, if ATC says, cleared for the approach via 12DME arc they will not expect you to go to OTEJE, they'll expect you to go to the VOR till joining the arc there.

Seems there's a disconnect from the Chief Counsel, the FAA, the USAF and pilot's in general.

Thanks for the nice discussion and staying on topic.

Me

 

[nosehair]

Seems there's a disconnect from the Chief Counsel, the FAA, the USAF and pilot's in general.

Thank you for acknowleding that fact. The Chief Counsel got there by not answering operational questions. He's a lawyer. He/They know how to legalspeak; they answer a question about a rule/procedure, and they answer with the exact same words in that rule/procedure. They are not gonna tell you that you can cut a corner, no matter how safe and practical it is.

They (the FAA) are not gonna come after you either. They can only come after you for violation of a regulation. Find the regulation that you can be violated with and you will have your answer.

 

[81Horse]

Okay, I'm going to own up to my lurid distant past: I once was an air traffic controller, and once upon a time I worked in a NON-radar approach control tower. Back in the day, DME arcs were used all the time at such places for the very reason we've been discussing: no PT's. (Arc transitions can be time-consuming, though.)

I can tell you it was common to allow arc intercepts inside the IAF; even an off-airways intercept can be positively positioned by asking the pilot to report the radial he's crossing on the arc.

Once established on the arc, inside the IAF, you are on a published segment of the approach. As a controller, I'd have been flabbergasted if a pilot had asked to return to the charted IAF on the arc and make a 180. I mean, WTF, over??

I don't know what planet that FAA opinion-writer flies over (if he's a pilot at all), but it's not Earth.

Somewhat off-topic: when a radar is finally installed in a non-radar terminal area, it turns for some time before it's commissioned for ATC use. You should see what pilot nav really looks like sometimes -- it would scare the hell out of you. Holding pattern entries? Hahahahahahaha ...

 

[avbug]

It may not be earth they're flying over, but it's on earth that the FAA Chief Legal Counsel will oppose you during the appeal process following enforcement action...and the legal interpretation is the teeth to do so. Disconnect or not.

Reality, vs. not.

Lots of pilots live with their heads in the clouds under the blissful assumption that the Administrator has better things to do than violate them for what they consider trivial humdrum. I can tell you from personal experience that is definitely not the case. For many inspectors, it's their entire purpose for being.

I know an inspector who violated a pilot for this very thing; failing to fly the full proceedure. He happened to be at KJAC when he saw the pilot do it and then proceeded to approach the pilot on the ground after he landed. Busted. (It wasn't an arc).

Did he violate six airmen, or was it just five? He honestly doesn't know, himself. But you gotta ask yourself one question. Do you feel lucky, punk? Well, do ya?

 

[Freight Dog]

Unless otherwise stated or given instructions from the controller, the ARC may be intercepted from anywhere. At a distance = to 1 to 2% of your groundspeed (150KIAS = 1.5-3.00NM), turn 90% and intercept the ARC. If you have an RMI, just turn 90 degrees and keep the needle pointed 90 degrees to your direction of travel. If you are getting blown towards the fix the ARC is based off of, put in some correction and if you are getting blown away from that fix, once again, put in correction. It really is just that simple. DME ARCs happen to be a great place to use the A/P in HEADING mode.

That's too much work. If it's a charted DME ARC and you're cleared for the approach, LNAV/VNAV do wonders.... Puerto Vallarta VORDME 22 comes to mind...

 

[DC8 Flyer]

On the airways. To OTEJE via V191 from the Thief River Falls VOR and the OTAXY on V430 from Devils Lake VOR

I might be looking at an old chart, but V430 is off the 270 radial, and according to the FAA I would have to be on the 269 radial, or 1/5 of a mile to the south, to legally start the approach. V191 is off teh 071 radial so if I was inbound from TVF, no prob, but if I was inbound from ROX on V171, I have to either track to the vor and then outbound on either the 269, 071 or the 003 radial to start the approach, or get radar vectors if available. Makes sense to me.

 

[CloudyIFR]

I might be looking at an old chart, but V430 is off the 270 radial, and according to the FAA I would have to be on the 269 radial, or 1/5 of a mile to the south, to legally start the approach. V191 is off teh 071 radial so if I was inbound from TVF, no prob, but if I was inbound from ROX on V171, I have to either track to the vor and then outbound on either the 269, 071 or the 003 radial to start the approach, or get radar vectors if available. Makes sense to me.

I saw that to. I wonder if it's just because the VOR needs an update due to Mag Var change or not. Wonder what the Lat/Long are for the two points as they may actually be the same point but time has required some adjustments.

Thanks everyone for the nice thread.

 

[DC8 Flyer]

I saw that to. I wonder if it's just because the VOR needs an update due to Mag Var change or not. Wonder what the Lat/Long are for the two points as they may actually be the same point but time has required some adjustments.

Thanks everyone for the nice thread.

All and all, we are splitting hairs, non radar, start the arc at the beginning to be legal, vectors, go wherever ATC tells you (yes yes, dont let ATC kill you).

Keep in mind, mag var will not change a VOR radial, it will only change the mag course across the ground. The radial is "fixed" and has to be manually "recalibrated" if thats the right word.

 

[atldc9]

I gues I have never seen that (doesnt mean it doesnt exist, just never seen it) I have seen an approach that is one continuous arc to the runway.

I am wondering if the person that wrote this letter misunderstood what was being asked, although I am not privy to the actual question. It would seem that if the FAA didn't want pilots intercepting arcs anywhere but the IAF on the arc there would be an easier way to answer the question. Or maybe I just have too simple of a mind.

Do you have any examples of an arc being part of a feeder route, that would be interesting to see. Also, any opinion on the GPS units being able to move the arc?

I used to teach at this airport. MTN in Baltimore, a continuous arc approach.

http://www.naco.faa.gov/d-tpp/0602/05222VDTZ15.PDF

 

[midlifeflyer]

Ah! The Martin State arc approach. A favorite for a session on a sim!

 

[Canucit]

jeez you guys are making my head hurt with all that tech jargon stuff

 

[Blackjet]

Ah! The Martin State arc approach. A favorite for a session on a sim!

I don't think that there is a better one for training than that one. Log after I had my Inst ticket, I worked with a corporate pilot to actually learn something about real world flying. He had a PC Training device that was FAA approved. He would have you shoot the Martin State full ARC and he would change the speed and the direction of the wind everytime I progressed 10 degrees. You wanna talk aobut wondering how you ever passed a checkride! When I finally figured out what he was doing, I was already well on the way to mastering that bad boy, but it did teach me alot, and I have no problems when given an ARC to this day. I think they are a challenge and a lot of fun. Now if only I could get a trip to the Baltimore area.

 

[paid4training]

Well I kindda feel like a dumba$$!!! I have no idea how to do a dme Arc. so this discussion is kindda depressing!!!! lol