Parallel Entry Technique

[EatSleepFly]

Who the heck is teaching people to try to intercept the inbound course before reaching the fix when doing parallel hold entries? And why?

Example: ATC instructs you to hold east on the 090 radial. You determine it is a parallel entry. You hit the fix, then fly 090 for one minute.

At this point, why do people turn around and try to intercept the radial before reaching the fix? Why not just center the CDI, and fly direct to the fix (thats how I was taught and how I teach it)? Its perfectly legal, and it saves a lot of frustration with a bunch of turning and overshooting. Several instrument rated pilots have told me "its the way I was taught" when I ask.

Is there some advantage to this method that I am missing here? Because it seems to me like a good way to screw yourself up. Any thoughts??

 

[pilot602]

I was taught to catch the radial when turning inbound off a parallel entry. And, I've found, that if I keep a standard rate turn going and turn to a 90 degree intercept and as soon as I hit the 90 degree mark roll out to the inbound heading I make it nearly every time.

Going straight to the fix gives you a longer turn (more than 180 degrees) outbound. Not a big deal, I guess, I just like a "straight" shot.

 

[E_Dawg]

I think the advantage (to me anyways) is that there is less fiddling with the CDI selector when you're getting established. I'd rather cross the fix, set my inbound course, and leave it there than have to reset it at least two more times if I wanted to go direct to after the turn outbound.

Also, you'd need more than a 180 turn to turn outbound after getting established.

 

[MikeD]

[ QUOTE ]
I think the advantage (to me anyways) is that there is less fiddling with the CDI selector when you're getting established. I'd rather cross the fix, set my inbound course, and leave it there than have to reset it at least two more times if I wanted to go direct to after the turn outbound.

Also, you'd need more than a 180 turn to turn outbound after getting established.

[/ QUOTE ]

On our HSIs, we have a bearing pointer that always points to the navaid, so it's convenient to leave the CDI on the holding radial, and still proceed direct to the fix. In a T-38 or similiar aircraft, a parallel entry will throw you far to the non-holding side of the radial upon initially crossing the fix outbound. If holding in the 280-300 kt range, you cover a lot of distance outbound prior to the inbound turn. Sometimes it's worthwhile to intercept the inbound course, sometimes not. However, there's nothing wrong with taking a "cut" towards the inbound course, especially for any known winds, and if you intercept the inbound radial, fine; if not, so what if you have to make an in-excess-of- 180 degree turn outbound?

But consider this....what are we really talking about? holding at a navaid? This I could see flying directly to the navaid on the inbound leg convenient. But.....

What if you're holding at a radial/DME, or even worse, holding at the intersection of two radials using two OBS/CDIs? I'd much rather re-intercept the inbound course especially this case, so I at least don't have two CDIs at full scale deflection, and hence, no true idea of exactly where I am over the ground in IMC........

Think about it.

 

[EatSleepFly]

Yeah, I guess I should have been a little more clear. I meant during a VOR or NDB hold.

My theory on it is that trying to re-intercept just creates the potential for a lot of turning/maneuvering. Depending on your groundspeed, you'll have to have a large intercept angle to get established on the inbound course prior to reaching the fix. Time and time again, I see people on IPC's in higher performance airplanes trying to re-intercept it, but their 175 knot groundspeed causes them to blow right through it. Personally, I would rather see people having to turn a little more than 180 in the outbound than end up in the non-protected area.

Anyways, good points, and thanks for the insight guys!

 

[MikeD]

[ QUOTE ]
Yeah, I guess I should have been a little more clear. I meant during a VOR or NDB hold.

My theory on it is that trying to re-intercept just creates the potential for a lot of turning/maneuvering. Depending on your groundspeed, you'll have to have a large intercept angle to get established on the inbound course prior to reaching the fix. Time and time again, I see people on IPC's in higher performance airplanes trying to re-intercept it, but their 175 knot groundspeed causes them to blow right through it. Personally, I would rather see people having to turn a little more than 180 in the outbound than end up in the non-protected area.

Anyways, thanks for the insight guys!

[/ QUOTE ]

It really all depends, ESF.

Consider this also for your example......

Say you have an outbound leg of 1 minute. You could fly inbound to the navaid, or take up an intercept heading for the inbound course. Now what if you have a tailwind on the inbound course? That would make intercepting the radial inbound impractical. But what if a good headwind on the inbound course? You could easily intercept the inbound.

But even better, what if the leg length is 10 DME in the hold? In this case, why not re intercept the inbound course, almost regardless of what kind of plane you're flying.

Answer overall: It just depends. There's no one answer, ESF. NO one technique is right or wrong over the other. I just wish pilots that do either technique could just explain why they do it one way or the other. And I would especially hope that instrument examiners aren't busting people over different techniqes being used.

Me? Sometimes yes, sometimes no. It's situation dependant.

 

[EatSleepFly]

[ QUOTE ]
NO one technique is right or wrong over the other.

[/ QUOTE ]

I agree. I didn't mean to imply that the other way of doing it was wrong...its just that it seems like everytime I give an IPC lately, people are having trouble re-intercepting that inbound course.

Maybe its not a matter of having enough time to get established on the course as much as it is a case of people not having fast enough scans to see that CDI needle coming in when they are using a huge intercept angle.

I see what you are saying though...that there are situations where one would be advantageous over the other.

In any case, this is just what I was looking for...thanks again!

 

[MikeD]

[ QUOTE ]
[ QUOTE ]
NO one technique is right or wrong over the other.

[/ QUOTE ]

I agree. I didn't mean to imply that the other way of doing it was wrong...its just that it seems like everytime I give an IPC lately, people are having trouble re-intercepting that inbound course.

Maybe its not a matter of having enough time to get established on the course as much as it is a case of people not having fast enough scans to see that CDI needle coming in when they are using a huge intercept angle.

I see what you are saying though...that there are situations where one would be advantageous over the other.

In any case, this is just what I was looking for...thanks again!

[/ QUOTE ]

And you're absolutely correct. Whe you ask someone why they do one technique or the other, they should be able to justify it and not be doing it on the misperceived notion that one way or the other is procedure.

 

[Center_Mid]

[ QUOTE ]
Yeah, I guess I should have been a little more clear. I meant during a VOR or NDB hold.

[/ QUOTE ]

My CFII taught me to intercept the inbound on a VOR hold, but to simply home in on the ADF for an NDB hold (simply because it's less complicated). When I posed your question to him, he agreed that you could vary the technique depending on the aircraft speed, the winds, and any clearance limits. He thought that the extra fiddling with the CDI could prove dangerous if you forgot to re-twist the CDI on your turn outbound, but so long as you remembered, the method would be fine.

 

[MidlifeFlyer]

ESF-

After reading your post and the replies, I'm still not sure we're all on the same page in the scenario. Anyway, I'm confused.

Are we talking about this? -

You are flying along southeast of XYZ VOR when ATC gives you "Proceed direct XYZ VOR. Hold west of XYZ VOR on the 270º radial...."

If you spin the OBS, you find that you are on the XYZ 150º radial.

Are you saying that some CFIs are teaching spinning the OBS to 270 or 090 and flying, say, 360 to intercept the holding radial east of the VOR instead of flying 330 direct to the VOR?

Are you saying that some CFIs are teaching

 

[mtsu_av8er]

[ QUOTE ]
[ QUOTE ]
And I would especially hope that instrument examiners aren't busting people over different techniqes being used.

[/ QUOTE ]

That's what I think is a bit scary....there are examiners doing that very thing.....for more than holding techniques.

 

[EatSleepFly]

[ QUOTE ]
Are you saying that some CFIs are teaching spinning the OBS to 270 or 090 and flying, say, 360 to intercept the holding radial east of the VOR instead of flying 330 direct to the VOR?


[/ QUOTE ]

Nope.

Using your example...

Once ATC clears you, you fly direct to the fix. Once crossing the fix, you fly 270 heading outbound (paralelling the inbound course) for one minute. You then make a left turn back around to return to the fix. At this point, you have two options:

1.) You can intercept that 270 radial inbound to the fix (your inbound course), or

2.) You can fly direct back to the fix.

Yes, flying direct will require more than 180 degrees of turn when you turn outbound. But so what? You're on the holding side, and you aren't at risk of busting into the unprotected airspace in the event of an overshoot while intercepting the 270 radial inbound- which is what I seem to be constantly seeing people do.

Heck, in a parallel hold entry, you have no choice but to turn more than 180 degrees in one of the turns...might as well make it the one on the safe side, right?

Anyways, I hope that clears things up at least a little. It would certainly be much easier to draw, if ya'll could see my white board!

Oh yeah...and like MikeD said- theres definitely arguments for both (although prior to my posting this thread, I hadn't heard a good argument for intercepting as opposed to going direct).

 

[MidlifeFlyer]

[ QUOTE ]
Nope.

[/ QUOTE ]Ah! Got it!

In that case. I'll agree with MikeD. Different strokes.

In the case of a DME or intersection hold, how would you fly back to the fix after a parallel entry =without= intercepting? (unless you had GPS with the fix in the database). There's a lot to be said for procedural consistency, so why not do the same with any VOR hold?

On the DE who busts someone for that? If you hear of one, feel free to suggest that they get in touch with the FAA Designee people for some recurrent training (not during a checkride, of course! Then, it's simple, "yes sir"). They'll tell him that he is not supposed to bust anyone for using any holding technique that keeps the airplane within protected airspace.

 

[MikeD]

[ QUOTE ]
[On the DE who busts someone for that? If you hear of one, feel free to suggest that they get in touch with the FAA Designee people for some recurrent training (not during a checkride, of course! Then, it's simple, "yes sir"). They'll tell him that he is not supposed to bust anyone for using any holding technique that keeps the airplane within protected airspace.

[/ QUOTE ]

I hate stupid-ass examiners, DE or otherwise, that grade on techniques versus procedures.

 

[aloft]

What do you know about surfing, major? You're from goddamed New Jersey!

 

[MikeD]

[ QUOTE ]
What do you know about surfing, major? You're from goddamed New Jersey!

[/ QUOTE ]

Lt.Col Kilgore is the man.

Charlie don't surf!

 

[sixpack]

I am!

I teach it one way, whether it a VOR, NDB, or LOCALIZER.
Consider the case where you have to hold at the IAF of a LOCALIZER approach (say, a fix along the localizer).
How would you navigate to the fix? ... by intercepting the course first!

True, you could do it differently for various navaids, and varying equipment in your plane, but sometimes it better to be consistent.

For what it's worth; I avoid parallel entries. I lean more towards teardrop and direct. There reason being, is that the parallel does not give you much opportunity to assess the winds during the inbound. The direct and teardrop give you a reasonable amount of time (usually 1 minute) on the first inbound to determine your wind correction.