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stankar
01-23-2010, 09:52 PM
I have the feeling that Holding Patterns is one of the neglected aspects of our hobby. I know that I have neglected it to some extent. But I believe that if we are to fly as accurately as possible under real-world conditions, we have to master this as well, particularly if we're flying IFR.

So.... having said that, I purchased a non-expensive Hold Computer from Sporty's - one of those rotating dial gadgets which help one visualize the hold entry pattern. What I found was that, although it works fine, it gives a hold entry pattern which is a mirror-image - both horizontal and vertical - to what it should be (and I know you're immediately saying "Hey, he's confusing radials with course" - but this is not so). I've also read some good tutorials on holds, particularly Paul Bertorelli's excellent article in AVweb (www.avweb.com/news/airman/18448-1.html), which corresponds exactly with my Hold Computer, and the How to...Fly a Hold by Jacques Zahar in our site, which exhibits the reverse situation as I described above.

Here is a typical example, illustrated by the attached pictures, and maybe somebody can comment on this:
You'll see the approach chart to Carlsbad/McClennan-Palomar in the one picture, which shows a hold being approached on a course of 326 degrees, with the inbound course of the hold on the 90 deg. radial. As depicted, this will clearly require a Parallel entry to fly along this radial to the fix. Now take a look at the photo I took of the same setup on my little computer, and you'll see the racecourse reversed, and this requires a Direct entry.

I can't make sense of this, and I'm not dyslexic, but either my computer is, or the approach chart is.

Stan

Stan

skylab
01-23-2010, 10:35 PM
The holding pattern in your computer shows an inbound of 270 instead of 090.

stankar
01-24-2010, 12:14 AM
Hey Skylab, you're absolutely right, it looks like I misinterpreted the computer instructions which say "Rotate the tab extending from the holding pattern to the assigned radial". To me this meant rotate the TAB side to the radial, namely 90 deg. but it actually means the other side of the tab, which is the HEADING. Well, the heading corresponds to the direction of the radial from the fix, so that makes sense, but the instructions are not clear (to me at least). Anyhow it works, so you've solved the problem, but I think its easy to get confused by this wording.

Thanks
Stan

stankar
01-24-2010, 01:01 AM
Skylab - again - sorry but we still have a problem. I checked the examples given in the computer instructions, and they all give the correct approach (according to the given answers) by setting the TAB to the holding inbound radial but there's no approach plate to compare with. Although your argument makes sense, there is still a discrepancy somewhere. In the example I gave, the hold entry is valid, but is reversed in relation to the approach plate. I'm now totally confused.

Stan

Amtran618
01-24-2010, 01:53 AM
http://map.aeroplanner.com/plates/FaaPlates_pdfs/05310VA.PDF

Chart of vor-a app into crq linked above holding instructions r given
Hold west of OCN on 270 radial, efc at xxxx hours

Not difficult.. if told to hold west of a fix, naturally the inbound course and heading are going to be east.. unless you have some kind of killer crosswind.. you dont need that cardbord just picture the fix and the hold and your position from the fix.. cake man

ReggieF5421
01-24-2010, 06:10 AM
One thing which might help is to let the default GPS fly the Approach and Hold for you in FS2004.

Approach the airport at an altitude above 3,000 ft and request the VOR-A approach with the OCN transition. Select that approach on the GPS and in the NAV/GPS mode the aircraft will enter the hold. The aircraft will fly the holding pattern for you so you can see how to calculate the activity.

You need to set the descent rate in the AP, and when you reach 3,000 ft, the aircraft will break out of the hold on the next pattern and complete the approach.

sandokan
01-24-2010, 06:31 AM
Hi,
The Holding pattern entry should be done according the approaching HDG to the Holding fix.
There are 3 approaching sectors as in the attached picture.
1-Parallel entry(sector 1)
Reaching the fix turn outbound and proceed for the expected time,then turn
left to return directly to the fix, then follow the Holding pattern.
2-Bisect angle line entry(sector 2)
When the fix is reached turn right for an HDG that diverges 30° from the outbound track.
When the expected time is over or the expected DME distance is reached turn right
again to intercept the inbound track.
When over the fix follow the Holding pattern
3-Direct entry(sector3)
When Fix is reached follow the Holding pattern.
Sandokan

skylab
01-24-2010, 09:35 AM
Well, I guess I was just lucky in that I was able to visualize getting into a holding pattern without the aid of a 'computer'. When all this started, way back when, instructors in the sim had all kinds of 'gouges' to try and help you get into these patterns from any sector. The 'big' one was putting your thumb on the RMI. Can't remember now what you were supposed to do from there on because, like I said, it just seemed natural to me how to get into the pattern no matter where you were coming from and no matter whether it was right or left turns. I think if you'll just look at your RMI or compass card and visualize the pattern, you'll find you can get in with no problem. And, remember this: these entry procedures are NOT mandatory. They are merely guides to help you get in. The main thing is you CANNOT exceed the boundaries of the pattern. I don't know what those are any more.

Have fun !!

Michael E.
01-24-2010, 10:25 AM
What he said. Instructors preach on and on about these procedures but they are only to help you establish yourself in the hold on the holding side and are not even manditory. However it gets you there safely and expediously is the correct entry. But will still ding you on the flight check.

I think the trick was to hold out your left hand with your thumb at about 40 degrees or so over the DG or RMI to visualize the entry. I found it a lot easier when my instructor would just leave me alone and stop talking.

stankar
01-24-2010, 11:18 AM
Thanks guys
I guess one can get too involved technically with this stuff instead of using common sense. My problem was actually the interpretation of the Sporty computer. Yes, following the instructions, you'll see from my screenshots that this got me onto an APPROACH RADIAL of 270, not 90. Going back to Paul Bertorelli's article, he says: "One thing the plastic plotters don't do is tell you the inbound and outbound courses... It's an excellent teaching aid but I found it has one confusing flaw. Controllers don't generally give the inbound, they give a cardinal direction and/or a specific radial 'Hold southwest on the 220 radial'. Sure, I can get the inbound by noodling the reciprocal, but if I'm going to use a crutch for this stuff, I want it do everything".

That's exactly what happened to me. When using this device you have to picture the scenario, and, depending on your approach course, if the inbound course doesn't correspond with the correct radial, you have to use the reciprocal. Clumsy, but there you have it.

Thanks for your contributions.
Stan

Amtran618
01-24-2010, 11:56 AM
Stank, the inbound course will always be the reciprocal of the radial.

stankar
01-24-2010, 01:36 PM
"Stank, the inbound course will always be the reciprocal of the radial."

Exactly Amtran! I was looking at the HEADING as the extension of the course, and of course the HEADING radial is outgoing in the same direction. The radial you're on is in the opposite direction to your course. You've got to keep your wits about you, and even after years of simming, I was slipping up on this basic issue. Thanks for reminding me.
Stan

nycpilot
01-24-2010, 01:45 PM
Technically, there is no specific way to enter a hold. All of the taught ways to enter into a hold are suggested. You can enter a hold anyway you want to. Actually there is a old joke in the pilot world. "How do you enter a hold?" - The answer is "the easiest way possible".

stankar
01-25-2010, 12:29 PM
I have finally reasoned out my misconceptions regarding holds, and at the risk of demonstrating how dumb I am, wish to share these observations with you to clarify the issue once and for all for the benefit of those who may experience similar problems.

The essence of the problem - as far as I was concerned - was that THE INBOUND COURSE IS A PART OF THE RACETRACK. Obvious? well it caused me confusion until I realized that you will never have a situation where the racetrack starts OUTBOUND from the fix. This means that when ATC specifies that you should hold on a particular radial, you'll ALWAYS be approaching the fix on a heading which is the reciprocal of the radial. How you ENTER the racetrack is another story of course, and that is where the hold computer might assist you to visualize what sector you're approaching from. In essence you need to visualize the racetrack and THEN consider how you're going to approach it.

Such a simple concept and yet it caused me such confusion.

Stan

skylab
01-25-2010, 01:57 PM
Not that any more need be said, but........ NORMALLY, you'll enter the hold on your present heading/course. You'll be tooling down an airway and ATC will say hold at such and such which is usually right on your airway ahead of you. Just get there and start holding...simple. Naturally, there are exceptions to this.:rolleyes: