DME Holds

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meritflyer

Well-Known Member
When holding on an airway at a DME fix with 1 mile legs and a parallel entry, would you still time the entry at 1 minute after crossing the fix before your turn to the inbound course or cross the DME fix then fly for 1 mile (instead of timing it) then turn back to intercept you course inbound?

Same example for if it was 5 mile legs. Cross the fix, fly for 5 miles prior to turning to intercept the inbound course or time it at the standard 1 min?
 
1 mile legs? That's essentially flying around in circles. I'm confused.

Anyways... DME holds are all DME, no timing. For your example- fly out 5 DME from the fix, then start your turn back to intercept.
 
I was taught that the entry procedures don't change ie. still use time (this is what the examiners in the area look for)....after reviewing the IFH now I am not so sure because it mentions that time is not used. However, if one has to do a teardrop entry would he fly X miles DME then turn inbound???
 
planejay said:
I was taught that the entry procedures don't change ie. still use time (this is what the examiners in the area look for)....after reviewing the IFH now I am not so sure because it mentions that time is not used. However, if one has to do a teardrop entry would he fly X miles DME then turn inbound???
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Sure, why not? I think we're still talking about a pattern where remaining in a protected area, rather than perfection is the goal.

Consider that DME is slant distance to begin with and that a DME hold at 3000 AGL will be in a different lateral distance from the fix than one at 10,000 AGL. I doubt X DME 30° off the inbound course will make much of a difference. And, the alternative is doing math :eek: .

Consider also that the DME given for a DME hold is an outbound number (unlike time) and that when your DME read 5 for the teardrop, you will probably be in the same place as when it reads 5 in a direct entry.
 
planejay said:
I was taught that the entry procedures don't change ie. still use time (this is what the examiners in the area look for)....??
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That's Old Fart Heaven for people like me who have the habit and we don't wanna give it up (or learn a new one). The idea is that if your DME quits, ya still got the time.

After all, we used to do it all on a compass and a watch.

"What's this button for?"
 
planejay said:
I was taught that the entry procedures don't change ie. still use time (this is what the examiners in the area look for)....after reviewing the IFH now I am not so sure because it mentions that time is not used. However, if one has to do a teardrop entry would he fly X miles DME then turn inbound???
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If you are going to do a teardrop, you are better off using time for the entry. If the wind is not in your favor and you do the 30 deg turn for the outbound leg, you can end up way out there. Especially if you get 10 mile legs.

For the other entries, it really doesn't matter. Since I am lazy, I would probably just use DME.
 
nosehair said:
That's Old Fart Heaven for people like me who have the habit and we don't wanna give it up (or learn a new one). The idea is that if your DME quits, ya still got the time.

After all, we used to do it all on a compass and a watch.

"What's this button for?"
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Ummmm....if your DME quits, how are you going to identify the holding fix?
 
Come on you guys, comparing apples to oranges. The point I was trying to make, was that it is pointless to time solely for the purpose of redundancy if we cannot identify the fix without DME anyway.
 
flyguy said:
Come on you guys, comparing apples to oranges. The point I was trying to make, was that it is pointless to time solely for the purpose of redundancy if we cannot identify the fix without DME anyway.
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I get the point and I think you're right on two counts. Even if it's a hold with a VOR as the fix, but the clearance is to fly X NM legs, if your DME quits, you are unable to fly the clearance.

I don't think there's a redundancy issue at all. AFAIK, timing is not an acceptable substitute for DME.
 
Whichever the hold is (timing or distance) the entire point of that time or distance is to keep you in a protected area. The entry is to get you into the hold. The inside of the holding area is all within your protected area. Therefore, use a minute as a standard. If you're cleared for 1nm legs then make sure a minute is not too long. And if it is, make it no longer than 1nm. If you're given 10nm legs, there is no point in making your entry leg 10nm. The main thing is to stay within your limit. Also keep in mind that the width of your hold is expected to be about waht it would take to make a 180 degree standard rate turn. Consider if you are given 10nm legs. If you make a teardrop entry you will travel 10nm at a 30 degree angle to the inbound leg. That could very easily put you out of your protected area. ...Just a few things to consider.


CFI, CFII, MEI
 
Yeah I'm not so sure bout using DME for entry's. The point of an entry is to get you established in the hold. Since it seems to be the favorite on this thread for some reason we'll use the teardrop. If you hit the fix proceed outboud on the correct heading per LARS if you went 10miles and then turned back to reintercept, with a standard rate turn you wouldn't reintercept the inbound course until really late. Maybe 1nm from the fix if that. If it were me flying, I'd just fly outbound a minute, make my turn, get established inbound, hit the fix and get established in the hold as soon as possible.
The biggest thing to consider with all this is speed obviously. Merit I think your still instructing in skyhawks and stuff so 10nm legs take 5 mins give or take. In a jet 10nm goes by pretty quick and just using DME on the entry vs. time wouldn't be a huge deal. By the time you get to jets I'm sure there is going to be a profile for it. Our initial training in the Baron we always did 10mile legs but for the entry's if we couldn't do direct we'd only proceed outbound a minute.
I was taught, I taught, and I currently use only time for entrys. (lol I probably coulda just wrote that...oh wells)
 
mikecweb said:
I was taught, I taught, and I currently use only time for entrys. (lol I probably coulda just wrote that...oh wells)
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That might work MOST of the time but take a severe case of a clearance consisting of 1nm legs. You're snailing around at 90kts because let's face it, you're in a hold... a calculated waste of time. So there's no need to be going fast in circles. That would only increase the number of circles you would need to make in the same amount of time, therefore increasing the pilot workload. And everyone knows we fly because we don't like to work. But I digress... so 1nm legs at 90kts. you fly for one minute with no wind and you're a half-mile past your clearance limit. Not trying to be nit-picky, just want to clarify that "rules-of-thumb" are exactly that.

CFI, CFII, MEI
 
I would use time to do the entry turn. Technique. Legally, how you enter the hold, how you fly it, and whether you are inverted are all up to you. Just stay in the protected airspace. Has anyone here ever actually been assigned a 1nm leg DME hold? I haven't.
 
JAM said:
I would use time to do the entry turn. Technique. Legally, how you enter the hold, how you fly it, and whether you are inverted are all up to you. Just stay in the protected airspace. Has anyone here ever actually been assigned a 1nm leg DME hold? I haven't.
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Actually the only holds I've ever been assigned have been published (which takes the guesswork out completely) or the only thing specified was the fix, and the cardinal direction, which unless I'm mistaken would mean one min legs, right turns, and outbound on the specified direction.

Inverted? Well if you are carying passengers you'd need parachutes as that would be a bank greater than 60 degrees and inverted holds are not a required maneuver toward any certificate or rating. You also would have to make sure you don't exceed any aircraft limitations. You'd have an engine failure in short order with a gravity fed fuel system and/or a wet sump oil system. Other than that I suppose legally you could do that. Actually, how would ATC know anyway? Just make sure you turn opposite the assigned direction to stay on the protected side.
 
On second thought, the inverted hold would not be legal if you are holding on an airway, as that would be considered aerobatic, and you cannot do aerobatics within 4nm of the centerline of a federal airway.
 
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