2 questions about instruments

kiwi lover

kiwi lover

New Member
I'm instrument rated, although it's been awhile (we're talking a few years) since I've put them to use. I'd like to get back into it.
I notice though that I've never once flown a DME arc approach, not even once in training, and if confronted with one would be baffled.
Can someone explain it in simple-English?

Secondly, entering a holding pattern: I did a search and got some insight but I'm still confused. Seems like every holding pattern I look at I think I should be making a teardrop entry LOL so I'm obviously doing something wrong.
Thanks for the help!
 
"un-able" is all you need to know :)
As far as the DME ARC, explaining it here would be cumbersome and easier to pull out the instrument book. There aren't any real tips or tricks I could give besides what they say in the book. Then grabbing a CFI and doing one will drive it home.

The holds tip: Think about which type of entry would make you turn the least, and there is your answer.
 
standardHoldingPattern.gif


A. Parallel.

B. Teardrop.

C. Direct.

http://www.meretrix.com/~harry/flying/notes/dmearc.html
 
I taught myself DME arcs on Microsoft Flight Sim in probably 30 minutes before my instructor and I covered them. There is a a lot of instructional info on the web about them.

I was getting nowhere quick (so it seemed)with holds after my first two lessons following basic attitude flying. I also completely mastered these using Flight Sim, and my books. I only imagine how much money it would've cost me to "get it" in the airplane with an instructor.
 
Holds are easy. Cross the fix and turn outbound. There's your entry. Seriously. Draw it out. Works every time.

-mini
 
I found something on DME arcs and have read that; it doesn't seem too difficult but need to do one myself sometime.

OK on holding patterns. If you're on a 120 heading, told to hold at a fix so you're inbound course is 190, what's the entry procedure?
I know there's the pen left/right method, how does that work though? Do My DG is saying I'm on the 120 heading.. help me from here, please..
 
kiwi lover said:
OK on holding patterns. If you're on a 120 heading, told to hold at a fix so you're inbound course is 190, what's the entry procedure?
I know there's the pen left/right method, how does that work though? Do My DG is saying I'm on the 120 heading.. help me from here, please..
Click to expand...


Get a sheet of paper. Draw the inbound course to the fix. Trace the direction you're coming from to that fix. What turns? Left or right? Turn that way. Hold. Repeat as necessary.
Its very easy. Stop making it hard. THERE ARE NO REQUIRED ENTRIES FOR HOLDS.
 
Run though this bad boy a bunch for holds.

http://www.lunabase.org/~faber/Vault/software/hold_quiz/

Or, just draw 'em out, which is what I'd have to do if I ever got an unpublished hold.

But yeah, the only time you need to worry about the "proper" entry is on a checkride or interview. Just maneuver so you stay on the protected side of the hold and you'll be fine. Cross the fix and turn outbound is good advice, it'll either make a direct or parallel entry.

For DME arcs, remember "turn 10, tune 10." Again, it's easier with a drawing, but think of flying the arc as a bunch of tangents.

Turn 90 degrees from whatever your heading is to join the arc (lead it by 1/2 to 1 mile for most training aircraft speeds), twist the OBS 10 degrees ahead. When the needle centers up, turn an additional 10 degrees, twist the OBS 10 degrees and repeat.

Depending on wind it might wind up being "turn 15, tune 10" or "turn 5, tune 10" on some segments but you'll get a feel for it as you fly the arc.

If you're inside the arc just fly the same heading until you're back on it. If your outside, turn more so you'll get back on it.

Keep in mind too, the protected airspace on an arc is the same as on an airway so if you're at the proper altitude you can be 4 miles off the centerline (6, technically) one way or the other and not hit anything.

Of course, we'd probably like to fly 'em a little more precisely than that most days. :)
 
Holocene said:
I remember reading that an examiner can NOT fail you for using whatever entry proceedure you want, within reason of course.
Click to expand...

That's entirely possible, I really don't remember the PTS. I was thinking more of 135/121 checks. Plus, doing the "recommended" entry gives the examiner one less reason to raise an eyebrow. :)
 
Thanks.
Yes I understand that, and looking at my example of flying 120 and entering a hold whose inbound course is 190, I would make a direct entry. It just makes sense. And in real life I know it's not essential to do it 'right'/
But for a checkride or interview, it is. That's what got me thinking; I was reading some gouges for various companies out of curiosity and most present you w/a missed approach to a hold and want to know what entry you'd use.
Let's say you're flying a heading of 180. The imbound course is 360, so you're flying right to the fix and opposite the inbound course. Direct entry would seem to make sense, right? But wouldn't you want to make a teardrop so you can align yourself once turned inbound???
:panic:
 
kiwi lover said:
Let's say you're flying a heading of 180. The imbound course is 360, so you're flying right to the fix and opposite the inbound course. Direct entry would seem to make sense, right? But wouldn't you want to make a teardrop so you can align yourself once turned inbound???
:panic:
Click to expand...

So, are you saying that the inbound course for the hold is in the opposite direction of your CURRENT heading? If so, then teardop entry.
 
Capt. Caucasian said:
So, are you saying that the inbound course for the hold is in the opposite direction of your CURRENT heading? If so, then teardop entry.
Click to expand...

Yes, you're heading is 180 degrees currently. You're going to hold south of XYZ on the 180 radial, right turns, yada yada yada

and yes mini, i'm saying it w/you lol

So in that situation, crossing the fix i'm already going outbound, but i need to turn to a teardrop to get aligned, if i'm right.
But the "raise the right" method doesn't work cuz if i'm heading 180, the reciprocal is in the direct area..
 
Do you have a sim? What I did was spin the unused no.2 obs while direct to a navaid on nav 1. What ever it landed on was my inbound course. Then, enter the hold, press pause, go to the map, and look at how bad you f'd it up. I guarantee you'll figure it out eventually.

It really does become very very simple after a short time.
 
no i dont' have a sim, unfortunatly.

I know I saw advertised somewhere (AOPA mag?, maybe Flight training) a course for like $30 you can do online thru Sporty's.. I checked their website but only can find their complete instrument course for a few hundred bucks.. i'd love to take the re-fresher though to sharpen the skills..
anyone know what i'm talking about?
 
Kiwi, if it's been long enough that you're really this ocnfused about holds, spring some bucks for a ground and flight session with a CFII.

Truth about holds is that (1) they tend to be made way more complicated than they need to be; (2) The plethora of tricks for figuring them out will confuse the crap out of you; (3) one pilot's trick might make no sense to another; and (4) shortcuts are not a replacement for understanding.
 
DME arc: Turn to the initial heading. If the number gets bigger, turn a little towards the VOR. The "turn 10, twist 10" thing gets old, make your life easy.

Hold: cross the fix, turn however you want, just stay on the protected side. Make your life easy.
 
2 other arc techniques:

The first only works if you have a bearing pointer, which many airplanes don't. But if you have a bearing pointer, you can keep that at the 90 degree index. Then, if you are inside the arc, displace it a little bit below the 90 degree index. If you are outside, displace it a little above the 90 degree index. Use about 5 degrees for every half mile you are off the arc when you are inside, and 10 degrees/half mile outside the arc.

If you don't have a bearing pointer, but you have a groundspeed readout based on DME, then it should be reading 0 when you are arcing. So you can cross check your heading that way.
 
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