Lead Radial

MauleSkinner said:
Years ago my older brother and I flew to Colorado for a ski trip...he was working on his instrument rating at the time, and I was an ATP making my living in King Airs, so we decided I'd give him some instrument instruction on the way.
He was starting to mumble about the setup and calculations involved, and how he was going to figure out headings and stuff since he was partial panel ( :D ), so I pointed out that it's just a 90-degree turn onto the arc (30 seconds on needle & ball), and then 3- to 5-second turns when the DME increases to the arc distance. #1 VOR on the ILS, #2 set for the lead radial. He gave me one of those "wow! That's way easier than what I was taught!" looks.

That wasn't the only epiphany he had that trip...he also realized that while little brother still didn't stand a chance in a fair fight (my brother was a West Point grad/Army ranger at the time), I could make life pretty miserable for him under the hood. ;)
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DME arc partial panel?! For shame.:D
 
GCA319 said:
...They had a very...technical way of doing things and it frequently took the student's attention from the simple task of flying the airplane.
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That's how I feel about the current fad of reading back every single word that ATC says!
 
Palmpilot said:
In case someone wants to look up the approach after the link expires, it's the VOR RWY 11 approach to Sloulin Field Intl (ISN) at Williston, North Dakota:

http://download.aopa.org/ustprocs/current/NC-1/isn_vor_rwy_11.pdf

The VOR/DME RWY 29 approach to the same airport does not have lead radials:

http://download.aopa.org/ustprocs/current/NC-1/isn_vor_dme_rwy_29.pdf
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It looks like the VOR/DME RWY 29 is gone and it's now the ILS or LOC RWY 29 with ADF or DME REQUIRED. The DME arcs do have lead radials
 
Palmpilot said:
"Different strokes for different folks." I got my instrument rating in a plane that didn't have GPS. I found "turn ten, twist ten" quite helpful.
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I never flew an airplane with DME when I got my rating. It wasn't until many years later when getting an IPC that I did it. The CFII gave me the turn 10 twist ten thing and it made sense and worked well. I've done it 20 and 20 since then and that keeps me in tolerance on the arc.
 
luvflyin said:
I never flew an airplane with DME when I got my rating. It wasn't until many years later when getting an IPC that I did it. The CFII gave me the turn 10 twist ten thing and it made sense and worked well. I've done it 20 and 20 since then and that keeps me in tolerance on the arc.
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I understand the "twist 20," but not the "turn 20."

Whatever number you choose, 10, 20 or whenever, "Twist," provides situational awareness of your progress along the arc. But what does "turn" a specific number of degrees at the same time as twisting give you that "turn whenever the DME readout is off by X" doesn't?
 
midlifeflyer said:
I understand the "twist 20," but not the "turn 20."

Whatever number you choose, 10, 20 or whenever, "Twist," provides situational awareness of your progress along the arc. But what does "turn" a specific number of degrees at the same time as twisting give you that "turn whenever the DME readout is off by X" doesn't?
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It gives you the opportunity to really screw yourself up in strong winds.
 
I don't
midlifeflyer said:
I understand the "twist 20," but not the "turn 20."

Whatever number you choose, 10, 20 or whenever, "Twist," provides situational awareness of your progress along the arc. But what does "turn" a specific number of degrees at the same time as twisting give you that "turn whenever the DME readout is off by X" doesn't?
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I'm pretty sure that my instrument instructor didn't say that turn ten, twist ten was the only way to do it.
 
Palmpilot said:
I don't

I'm pretty sure that my instrument instructor didn't say that turn ten, twist ten was the only way to do it.
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Of course not. It's not about the 10. It's not even about the twist. I understand twisting every 10 degrees for situational awareness along the arc, although I don't personally think it's necessary.

But I don't understand the when you twist, turn the same number of degrees you twisted part of the mantra.

You have a DME readout and are trying to maintain that distance within a certain tolerance. You turn when you need to, just like tracking any other course.

Maybe the idea is to remind you to look at the DME when you twist, basically a mnemonic just in case you have not been paying attention to the main piece navigation information for the procedure :dunno:. But based on hearing pilots "afraid" the "difficult" arc, I think "turn 10" over-complicates what is really a very simple procedure for which we have created some trees to hide the forest.
 
midlifeflyer said:
I like it. Sure, I would know which wingtip pointed to the VOR, but the turn away from the VOR onto the FAC is a wonderful "twist."
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That one is a local favorite for practicing DME arcs. It's not the only one around, but it's a LONG one. Even if it turns the wrong way....

And you can do it for real in IMC. The high minimum sucks, but it's sometimes below the marine layer.
 
Palmpilot said:
I think I read in some thread or another that that approach might be going away, so I am attaching the PDF for posterity.
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I sure hope not, 'cause that's the only approach at that airport that doesn't oppose normal VFR traffic.
 
Palmpilot said:
I think I read in some thread or another that that approach might be going away, so I am attaching the PDF for posterity.
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Not indicated in the production plan tab at the IFP Gateway.
 
mtuomi said:
Out of curiosity, what makes that DME arc special? I don't understand what's weird about that one?
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I think it's fairly unusual to have an arc that turns away from the airport instead of toward it.
 
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I'm still waiting for those promised curved flight paths and entrances to an approach from anywhere above it the FAA promised us with MLS!! LOL.

We did finally kinda get "free flight" though. In a weird way.

"Cleared direct XXX."
"Unable, we're slant Uniform equipped. But we can take a vector until receiving..."

Haha. They never would have given those vectors for 300 miles back in the day. Not even if you asked. LOL.

But VOR based RNAV and MLS... man we were gonna have it ALL baby!! Hahah.
 
Gotta say it. Everytime I see this thread title, I'm picturing one of these

4bd8573fbc0e7dc314ef6b5920417ab8.jpg


made from the metal with the chemical symbol Pb.

Strange, I know...


Sent from my iPad using Tapatalk
 
aterpster said:
When did they do that?
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It was the marketing spin on the Microwave Landing System stuff. 80s I suppose?

Around here it got deployed for Rocky Mtn Airways at their expense and unpublished approaches. FAA approved of course, but the general pipe dreams of MLS never arrived.

You know the usual promises of any new tech in the NTS... "more safety, more runway utilization, the whole world gets unicorns and rainbow farts" ...

Like ADS-B and the mandate. My teeth will be whiter and my breath will be minty fresh.

I may have embellished there a bit. LOL. ;-)
 
denverpilot said:
You know the usual promises of any new tech in the NTS... "more safety, more runway utilization, the whole world gets unicorns and rainbow farts" ...
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And "circular runways will eliminate crosswind landings." :rofl:
 
denverpilot said:
It was the marketing spin on the Microwave Landing System stuff. 80s I suppose?

Around here it got deployed for Rocky Mtn Airways at their expense and unpublished approaches. FAA approved of course, but the general pipe dreams of MLS never arrived.

You know the usual promises of any new tech in the NTS... "more safety, more runway utilization, the whole world gets unicorns and rainbow farts" ...

Like ADS-B and the mandate. My teeth will be whiter and my breath will be minty fresh.

I may have embellished there a bit. LOL. ;-)
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Actually, you didn't embellished it much at all.
 
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