Understanding how to fly a holding pattern

Ok, question came up today... hangar debate ensued (ground school classroom actually)....

So you are flying an airplane equipped with a single nav radio. you are giving instruction to hold as published over a VOR. you nail your wind correction inbound at 9 degrees. commonly taught guidance is to triple your outbound wind correction.

now this old guy starts jumping up and down and getting all huffy, saying you never want to do more than double because you don't want to full scale deflect your OBS on the outbound leg.

the rest of us were drooped jaw in bewilderment. the old guy contends "he wants to know where he is in relation to the VOR and can count the dots and figure it out" sure, yes you can do that but we were like "why would you want to?" (also, later while actually flying... it makes for a super tight pattern...)

in our minds - you are on the protected side and a standard rate turn from the outbound with a double wind correction would have you blowing through the holding radial. (and if we really needed to know where... we could just twist the OBS...)

the old guy claimed no, so we loaded up and went out and flew it, sure enough - we blew through the holding course. yea, could have turned more aggressively but again - why ?(contention being, more than standard rate may possibly cause unnecessary spatial disorientation) the old guy got mad and said you young guys don't know how to fly and mumbled to himself the rest of the flight.

Soooo - without further ado (I hope I explained the situation enough), does anyone see the logic in what this guy was saying ? anyone ever hear of anything like this ?
 
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jaybee said:
Ok, question came up today... hangar debate ensued (ground school classroom actually)....

So you are flying an airplane equipped with a single nav radio. you are giving instruction to hold as published over a VOR. you nail your wind correction inbound at 9 degrees. commonly taught guidance is to triple your outbound wind correction.

now this old guy starts jumping up and down and getting all huffy, saying you never want to do more than double because you don't want to full scale deflect your OBS on the outbound leg.

the rest of us were drooped jaw in bewilderment. the old guy contends "he wants to know where he is in relation to the VOR and can count the dots and figure it out" sure, yes you can do that but we were like "why would you want to?" (also, later while actually flying... it makes for a super tight pattern...)

in our minds - you are on the protected side and a standard rate turn from the outbound with a double wind correction would have you blowing through the holding radial.

the old guy claimed no, so we loaded up and went out and flew it, sure enough - we blew through the holding course. yea, could have turned more aggressively but again - why ?(contention being, more than standard rate may possibly cause unnecessary spatial disorientation) the old guy got mad and said you young guys don't know how to fly and mumbled to himself the rest of the flight.

Soooo - without further ado (I hope I explained the situation enough), does anyone see the logic in what this guy was saying ?
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Not so much logic, but the old guy is probably remembering the old days when the guidance was to only double your inbound wind correction on the outbound leg. I never heard anything about avoiding going full scale deflection on the outbound leg. That me be his OPINION, like a lot of other items in this thread, but it was never a requirement.
 
Everskyward said:
Not so much logic, but the old guy is probably remembering the old days when the guidance was to only double your inbound wind correction on the outbound leg. I never heard anything about avoiding going full scale deflection on the outbound leg. That me be his OPINION, like a lot of other items in this thread, but it was never a requirement.
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Roger that, just trying to give the benefit of doubt, see if from his angle and maybe learn something I didn't know.

I'm drawing a complete blank on why anyone would want to know where they are on the outbound leg if you are intercepting and tracking inbound just fine.
 
jaybee said:
Soooo - without further ado (I hope I explained the situation enough), does anyone see the logic in what this guy was saying ? anyone ever hear of anything like this ?
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None whatsoever.
 
jaybee said:
...does anyone see the logic in what this guy was saying ? anyone ever hear of anything like this ?
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No. You're only outbound for 60 seconds. From the abeam position, you ARE full-scale off already. Tripling the wca works for a direct crosswind, less than that amount of crosswind three times is overkill, so the answer is somewhere between two and three times the inbound wca. I like three unless it proves to be too much.

dtuuri
 
Are you doubling or tripling the WCA on the 1-minute outbound leg to account for the wind drift that already occurred during your 1 minute turn to the outbound leg and will still occur during your 1-minute turn back to the inbound leg? Is that the theory?
 
dtuuri said:
No. You're only outbound for 60 seconds. From the abeam position, you ARE full-scale off already. Tripling the wca works for a direct crosswind, less than that amount of crosswind three times is overkill, so the answer is somewhere between two and three times the inbound wca. I like three unless it proves to be too much.

dtuuri
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Yes, that is what confused me so much about what the guy was saying :confused:

Yes triple is sometimes too much but that brings another point of contention, if it takes two, three, four laps or more to get it just right, nobody cares :eek:

Now with practice, you can usually nail after the second lap depending how good of WCA you get on your inbound, etc, etc
 
I was taught that it's a good thing to keep the needle pinned to the wall on the outbound leg.... Lots harder to overshoot the inbound leg turning inbound, and if the needle doesn't start to move off the wall on the inbound turn, shallow or stop your turn 30 degrees short until it moves.

So I will say that no I don't agree with the old man here.
 
register@teamandras.com said:
Are you doubling or tripling the WCA on the 1-minute outbound leg to account for the wind drift that already occurred during your 1 minute turn to the outbound leg and will still occur during your 1-minute turn back to the inbound leg? Is that the theory?
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I believe you're correct. Main reason being that the turn is always standard rate, not like turns around a point where you adjust your bank angle to keep the turn radius the same throughout.
 
Why would you ever be full scale deflection on the inbound. It is a track, not a heading.
 
Who said anything about a full scale deflection on the inbound course?
 
dtuuri said:
No. You're only outbound for 60 seconds. From the abeam position, you ARE full-scale off already. Tripling the wca works for a direct crosswind, less than that amount of crosswind three times is overkill, so the answer is somewhere between two and three times the inbound wca. I like three unless it proves to be too much.

dtuuri
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As you know you are outbound 60 seconds for the first outbound turn. Subsequent outbound legs are adjusted so that the inbound leg will be 60 seconds. But, for DME or RNAV holding the turn inbound is started with the charted holding distance is reached. Alas, when positive course guidance (PCG) holding was formulated by the "gurus" at RTCA they did not read the AIM correctly nor were any of them pilots. So, they designed the algorithm to begin the turn inbound so to roll out at the charted holding distance. With a very tailwind this results in flying an excessive distance outbound.

Every FMS and panel mount navigator that has PCG holding has this problem. As a practical matter it doesn't make any difference in low altitude light airplane operations. But, it does in jet airplanes even at altitudes as low as the mid-teens, but especially in the flight levels. Add to that the fact that some of the templates designed in 1963 have insufficient assumptions about jet stream characteristics, and containment can, and is, breached during extreme jet stream conditions.
 
How low can the jet stream get? Is it always high enough to guarantee terrain clearance when you're in it?
 
Palmpilot said:
How low can the jet stream get? Is it always high enough to guarantee terrain clearance when you're in it?
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I don't think the problem is with terrain clearance, just that if you get outside the protected area you might be in the way of other traffic. Probably not, but it is a theoretical possibility. Most (all?) of the holding I've done in a jet did not have any terrain issues.
 
Palmpilot said:
How low can the jet stream get? Is it always high enough to guarantee terrain clearance when you're in it?
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Terrain clearance isn't the issue by the time the winds get really strong. But, containment is. In busy airspace, those patterns can become so saturated with traffic that the centers have to use non-radar separation.

An associate of mine who is heavily into this subject flew the HILPT at KALS RNAV Rwy 20 in a Lear simulator with a 70 knot adverse wind. Containment wasn't breached. That HILPT is particularly critical because of higher terrain adjacent to the holding pattern.

But, even as low as the mid-20s winds can exceed 150 knots on occasion. But, not at 14,000.
 
On a similar topic, does anyone have a recommendation in San Diego for a top notch CFII who can actually teach? I flew with two recently who sucked at teaching and spoke with a couple more who did not really understand how to explain holds and DME arcs.

Scott
 
Blueangel said:
On a similar topic, does anyone have a recommendation in San Diego for a top notch CFII who can actually teach? I flew with two recently who sucked at teaching and spoke with a couple more who did not really understand how to explain holds and DME arcs.

Scott
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All CFIIs have to explain this stuff not only for the double I, but even for the instrument rating before that. You will too. What do you mean the CFIIs you "talked to" couldn't teach? Did you pay them for ground instruction or catch them at the coffee machine and didn't like the impromptu discussion that evolved? This subject is more than adequately discussed in books and online. My website has a couple of tutorials that have turned the lights on for some, for instance. You can use MSFS to teach yourself if you like. Heck, if you can't figure out hold entries after this thread, well... :dunno:

dtuuri
 
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Larry in TN said:
Here's a better graphic...
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I've been thinkin'. Y'know, that really is a good graphic. :yes: Very succinct. For the OP, I drew the holding pattern for the original scenario in post #1 (right turns) and compared it to determining the entry for a non-standard pattern (left turns). Since the heading in Larry in TN's illustration is 270° and not 120°, I moved the holding radial clockwise to preserve the 90° angle of interception:

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Aside to Mark: I'm curious how your first CFII had a way to draw the holding patterns at the bottom, based on locating the inbound course rather than the outbound. Seems "crazy" to me too. :confused:

dtuuri
 

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Thanks guys your explanations and drawings are very helpful. I am surprised that of the four CFII I spoke with not one could break down how a holding pattern works. It is like they expected me to already know what one was about perfectly. I had the same issue in calculus math courses when instructors assumed that you already knew differential equations.
 
That's similar to the way I learned. I just found it easy to remember that the teardrop entry is the same direction(left or right) as the hold turns, and you get 70 degrees in that direction. Other way 110 is parallel and the rest is direct.
 
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