Dissecting the hold: despite currency requirements, for-real holds are too rare for us to stay proficient. Understanding them is easy if we break them down to the basics.
For the most part, holding can be relatively simple: Fly to the fix and turn right. But it also can get a bit complicated if the hold isn't published. And there are ways to avoid it entirely if you're willing to play ball with ATC and eliminate the reason for the hold. Let's explore.
The FAA's Instrument Flying Handbook, FAA-H-8083-15, defines holding as "a predetermined maneuver that keeps aircraft within a specified airspace while awaiting further clearance from ATC." Another definition might be "boring racetrack-shaped holes in the sky while ground crews plow snow," since closed runways at our destination are often the reason for a hold.
Regardless, each holding pattern clearance has three basic elements: the direction to hold from the holding fix, the holding fix itself and the "expect further clearance time" (EFC), the point by which ATC expects to either send you on your way or give you another EFC. If the hold ATC is giving you is published--depicted on a chart you should have in the cockpit--those three bits of information are likely to be the only clues ATC shares with you on where you're supposed to go, which way you're supposed to turn once established in the hold and how long you'll be there. That's fine, since you already should know the rest, including how to enter the hold, at what speed to hold, how long you should fly each holding-pattern leg and which direction to turn. If you've forgotten these basics, or need a refresher, the sidebar on page 14 highlights them for you.
All of which is for a standard holding pattern, i.e., one that's published. But we also can be sent into a holding pattern pretty much anywhere, depending on ATC's needs. When we get a non-published hold, we need more information than the three items previously mentioned.
A clearance into a non-standard hold also will include the direction from the fix in which ATC intends us to hold, the fix itself and an EFC time, just like a standard hold. But since the intended holding pattern isn't helpfully depicted on a chart, ATC also will provide the inbound course. This will be the radial, course, bearing, track, azimuth, airway or route on which the aircraft is to hold. Also to be specified by ATC in the clearance is the outbound leg length--minutes or miles, usually DME miles, but the pilot can request it in minutes or the controller may want it in minutes.
The direction to turn in a nonstandard hold will be issued only if the controller wants you to turn left; otherwise, make right turns, just as if in a standard/published holding pattern. Finally, and as with the standard hold, you also should get an EFC time, perhaps along with any pertinent information on the reason for the delay.
IN THE HOLD
Once we've entered the hold (see the sidebar on page 15 to help determine which of the three recommended holding pattern entries should be used and when) we'll likely be a bit busier than we were a few moments before. For one thing, we'll need to monitor our outbound leg timing to ensure we're flying the prescribed hold. For another, we'll be making a roughly 180-degree turn as frequently as every minute. Finally, we'll need to monitor the wind's effect on the pattern we're flying. Timing or measuring the outbound leg begins when we level the wings abeam the holding fix. In this case, "abeam" really means a position roughly parallel to the hold's inbound course and headed in the opposite direction. The catch is--after the first lap around the hold--we should have a good idea of what the wind is doing to us and, using that information, plan to roll out of the turn to the abeam position after applying the appropriate wind correction. In other words, rarely will we roll out abeam the holding fix on the inbound course's reciprocal heading.
If we're flying a time-based pattern, wind also affects how long it takes to fly the inbound leg, the one determining our holding pattern's size. We need to time both the inbound and outbound legs, adjusting the outbound leg's length so we fly the inbound leg as prescribed.
When turning at the end of the outbound leg, we'll also want to apply some wind correction, with the idea of rolling out precisely on the prescribed holding course. The amount of correction applied likely won't be equal to and opposite to what we applied in the turn to the abeam point. Why? Because the wind will be acting differently on the airplane at each end of the hold--we might have a tailwind going one way and a headwind the other, for example--forcing a different amount of correction as we roll out of the turn at each end of the pattern. In no case, however, should we alter the turn itself in anticipation of the wind's effects--it should always be at standard rate, in the correct direction, of course, and designed to roll out on a heading which automagically applies the desired wind correction.
How do we know if we've applied the necessary wind correction? When we roll out of the outbound end's turn exactly on the holding course, that's when. If that happens, whatever you did on the last lap around the hold, keep doing it. As you fly the inbound leg, start planning the turn, the outbound leg and the turn after it.
Despite the higher workload a hold demands, we still need to be planning ahead. For example, we should already know the reason for the hold--traffic, weather, a gear-up incident closing the only runway at our destination, etc. Although we also should have an EFC time, those have been known to be extended--ATC is supposed to tell us when the delay is expected to extend beyond an hour or when a revised EFC is necessary.
According to the Instrument Flying Handbook, a clearance limit may not indicate which approach procedures will be used in a terminal area having a number of navigation aids and approach procedures. The IFH suggests ATC will advise the flight on initial contact, or as soon as possible thereafter, which type of approach you should anticipate. Even though it's a busy time, getting that information and digging out the appropriate approach plate is one task you should consider while in the hold.
Of course, receiving a lengthy hold is sufficient reason to start exploring other options, in our book. For one thing, we need to evaluate our fuel situation. Of course, pulling back the power for best endurance is always good operating practice when holding. For another, racing around a holding pattern in IMC might be good experience, but we'd prefer diverting to a nearby airport if it looks like we'll be a while getting to our destination.
The idea of thinking ahead in the hold also applies well before entering it. When ATC advises you to expect a hold or clears you to someplace that's not an airport, start thinking about your options. Again, a diversion is one of them. Slowing down is another good one--and our personal favorite--as is querying ATC about the reason for the hold and whether an alternate routing would make it unnecessary. These steps can eliminate the need for holding and--while perhaps not getting you to your destination any faster--might help minimize or eliminate the hold altogether.
Finally, and as much as we might want to, leaving the hold is possible only when ATC issues another clearance, we reach our EFC and have lost two-way radio communications, or cancel IFR when in VMC and proceed in VFR conditions.
NO HOLDS BARRED
Of course, modern ATC management techniques and improved surveillance means the hold is rather rare. That doesn't mean we shouldn't know how to enter, fly or depart one, however. Meanwhile, when the FAA revised FAR 61.57 a few years back, it added holds as a required IPC item, as well as one we need to track in our logbook or some other record to demonstrate IFR currency.
On the whole, we'd rather avoid them by slowing down or going someplace else. But when we do get one, we take great pleasure in being able to fly them precisely, with appropriate wind correction and leg timing. You should, too.
RELATED ARTILCE: Holding Pattern Elements
Regardless of where and when you're cleared into a hold, or whether it's published, each holding pattern has the same basic elements. The diagram below depicts a standard (right-hand turns) hold.
A Vortac, intersection, waypoint or other identifiable location--like a DME fix--at which the hold is to occur. You can't proceed beyond this fix until cleared out of the hold.
The holding side is the one on which turns are to be made and is "protected" by ATC, which will keep potentially conflicting traffic a distance | away. The non-holding side is not so protected.
The inbound leg is the one flown when approaching the holding fix, beyond which usually lies the flight's destination or next en route waypoint. The outbound leg is the opposite side of the racetrack oval and begins when abeam the holding fix.
The holding course is the one to be flown when established on the inbound leg and approaching the holding fix. If you're lucky, it's also the airway or terminal route segment on which you approach the holding fix, making the pattern entry a no-brainer.
The curved portions of the racetrack oval, where the aircraft is turning to align itself with the outbound and inbound legs. In a no-wind situation involving a standard holding pattern, these can be flown with a one-minute standard-rate (three degrees per second) turn.
RELATED ARTICLE: Holding Pattern Basics
Many aspects of entering and flying a holding pattern are things we're expected to know before taking off. In addition to the hold's depiction in the sidebar on page 13 and descriptions of the three basic entry methods in the one on the opposite page, the following merely should be a refresher. Flight?
DIRECTION OF TURNS
Unless otherwise specified in the clearance or the way in which the published hold is depicted, all turns are to the right. The only real challenge here is entering the hold if a course reversal is necessary, in which case the three basic entry methods discussed in the sidebar on the opposite page should be used.
The inbound course should be obvious. It is the radial, course, bearing, track, azimuth, airway or route on which the aircraft is to hold. When flying it on the inbound leg, wind correction should be applied to track it to the holding fix. In each turn and on the outbound leg, additional wind correction should be applied. The idea is to describe a near-perfect racetrack oval, despite the wind.
The altitude at which to fly the hold is the last one specified in your clearance. Often, when holding in terminal airspace for approach sequencing, ATC will clear the lowest aircraft in the hold for an approach and then descend the next-highest one, etc. Unless ATC specifies otherwise, that's the only time you should worry about what altitude to fly in a holding pattern.
The standard holding pattern has a one-minute inbound leg when at or below 14,000 feet msl and 1.5-minute when above. Anything else--two-minutes, five miles, etc.--will be specified by ATC. Pilots can request a different leg length if they want it; we'd suggest making the request before entering the hold so the controller can approve and plan for it in advance.
The maximum airspeed at which to fly a holding pattern is based on altitude and presented in the table below. Some published holds also include a maximum speed, which is included in the chart depiction. For most personal aircraft, speed limitations are not something we need to worry about and--since we're going nowhere in a hurry when holding--we'd suggest flying the hold at best-endurance power.
Maximum holding Airspeed Is Based On Altitude Altitute Maximum speed 0-6000 Feet MSL 200 KIAS 6001-14,000 Feet MSL 230 KIAS Above 14,000 Feet MSL 265 KIAS
LEAVING THE FIX
When to leave the fix is specified by ATC in the form of an expect-further-clearance time when the hold is issued. In the case of lost communication, the hold should be planned--by reducing, but never lengthening outbound and inbound legs to depart the holding fix at the EFC time.
RELATED ARTICLE: HOLDING PATTERN ENTRIES
When pilots sit down to discuss the correct way to enter a holding pattern, a lot of coffee can be consumed--and more than a few cockpit gadgets have been sold--before understanding is reached. Which is a shame, because holds aren't that frequent (except on checkrides and IPCs) and the answer should be fairly obvious.
At below left is the FAA-standard diagram presenting the recommended 70-degree line through the holding fix, with the inbound course bisecting it and the resulting pattern entry maneuver depicted.
One of the key things to remember when planning to enter the hold is these are recommended entries--nowhere does the FAA say these entry maneuvers are required. If you really want to, you can perform a Split-S to enter the hold as long as you don't leave its protected airspace, the size of which varies with altitude, aircraft speed and distance from the fix-defining navaids.
Another thing to remember is when flying the direct entry, fly to the holding fix, then turn for the outbound leg. Fly it the prescribed distance/time, then turn back toward the holding fix and fly inbound. With either the parallel or teardrop, you don't want to fly beyond the maximum leg length for the hold's altitude or that specified in the clearance.
BY JOSEPH E. (JEB) BURNSIDE
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|Title Annotation:||INSTRUMENT FLIGHT|
|Author:||Burnside, Joseph E.|
|Date:||Aug 1, 2011|
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