how to fly a holding pattern
TRANSCRIPT
-
8/6/2019 How to Fly a Holding Pattern
1/16
How to. Fly a Holdby Jacques Zahar, CFI(Note this page is best viewed with a 1024X768 resolution)
Basically, a Hold is for airplanes like a stoplight for cars. Except that you cant put the parking brake on in
flight.
The purpose is to have the plane wait at a specified part of airspace (Protected airspace) until the trafficahead of your plane is far away enough or has landed.
Though Holding instructions are seldom ever used under the Procontroller/Squawkbox virtual ATC environment,
on very congested areas (Fly-ins) or simply for practice, it can be interesting both for ATC and Pilot if Hold is
accepted and flown.
The purpose of these pages is to give Virtual Pilots a way to fly a Hold manually.
This section will be divided into 4 sections:
1- Holding Clearances: How to decipher holding clearances
2- Types of entry: Depending on your location, how to enter a holding pattern properly
3- Flying a Hold: Principles of holding
4- Exiting a Hold: What to do next?
Before having a look at holding clearances, lets see the basic elements of a Holding pattern :
Without crosswind, a Holding pattern is like a racetrack:
See the arrows? They indicate the turn direction. A holding pattern with right turns is called a standard hold, one
with left turns is called a non-standard hold. This is important to know, as some ATC can say standard instead
of right turns or assume that the hold will be standard if they dont specify the direction of the turns.
-
8/6/2019 How to Fly a Holding Pattern
2/16
See also the inbound leg: this is the leg to which ATC refers to when giving the clearance, it is always going to
and finishing at the holding fix. The inbound leg should be flown forONE minute if below 14000 feet orONE
minute if above 14000feet unless otherwise specified. The outbound leg is not timed and depending on thewind can take more or less time than the inbound leg.
Note that ATC can also give DMEHolds, in which case ATC will specify the distances from the navigation aid at
which the inbound and outbound legs are to be terminated. In this case no timing should occur, since the DME
distances given describe the end of the inbound leg and the start of the turn outbound, and the end of the
outbound leg and the start of the turn inbound.
Last, look at the turns. No radius is specified here since they are all standard rate turns (3 per second) in a hold.Its time to use the small airplane of your turn coordinator !
1- Holding clearances:
-
8/6/2019 How to Fly a Holding Pattern
3/16
Note that not all holds are issued by ATC. One can have to hold without specific instructions if the last point you
have been cleared to is reached without further ATC instructions (ATC is sometimes busy) or when
communications have been lost. In that case use a standard pattern (right turns) upon reaching the lastassigned fix.
ATC issues holding instructions in the following form:- Geographical reference of the Holding fix: the general location of the holding
- Inbound leg: the inbound leg is always the reference
- Turn direction: (right turns (standard) or left turns (non-standard)
-
Altitude- Expected further clearance time (EFC)
- Current time (optional)
For example: C-GSRW, hold north-west of the Mirabel VOR on the 330 degrees radial, left turns, maintain 5000
feet, expect further clearance at 1730, time is 1712
hold north-west
The general direction of the holding patterns inbound leg in reference of the holding fix, using geographical
directions (N, NE, E, SE, S, SW, W, NW,)
-
8/6/2019 How to Fly a Holding Pattern
4/16
the Mirabel VOR..The holding fix. This can be a VOR, an NDB, or a Fix
(intersection)
or even a Marker beacon.
A holding fix can also be defined via DME distances,
in that instance a radial and DM
E distance are given.
on the 330 degrees radial
The track upon which the holding patterns inbound leg is
located
left turns
Obvious. Note that the turns used to enter the hold are not considered.
Once you are established in the hold, all your turns will be as instructed,in our case this one is a non-standard pattern.
maintain 5000 feet
the assigned altitude
expect further clearance at 1730..
the expected departure time from the holding fix.
This doesnt necessarily means that youll be leaving the hold at that time (ATC can release you earlier atanytime), but in case of lost radio communications during the hold, you are expected to hold until the EFC and
proceed as filed or land if it was planned. So before accepting a holding clearance (by reading it back),
always check your remaining fuel and NEVER accept EFC that can compromise your fuel reserves and
alternate airport requirement.
Note: sometimes ATC can issue abbreviated holding instructions, if the hold is published on the HI/LO maps or
the approach plates. In that case it will simply say as published or as charted.
-
8/6/2019 How to Fly a Holding Pattern
5/16
Okay, weve copied and readback the holding clearance, now its time to figure out where and how to enter
this pattern.
1-The first thing to do upon receiving an holding clearance is to check the EFC against the remaining fuel.
2-The second is to reduce airspeed if you are within 3 minutes of the holding fix or ask the ATC for a speed
reduction if you are further than 3 minutes. Holdings are here to have you to wait, so why not reduce your
speed ASAP and save fuel at the same time? If youre lucky, by the time you have reached the holding fix at
reduced speed, the hold wont be needed anymore!
Moreover the extra time will help you figure out where
you are from the fix, and how to enter the holding
pattern.
There is a holding speed limitation in a Hold, based on
the following limitations (Note: this is based on
Canadian regulations, check your local ones).
IAS stands for Indicated airspeed, in knots.
3-The third thing is to fly direct the holding fix, in order to
become oriented and set-up the entry procedure.
Heres an easy way to visualize where is the Holding
pattern considering your position, by using your
directional gyro (DG) or your Horizontal situation
Propeller
aircrafts(including
turboprops)
175 Kts IAS
Civil turbojets230 Kts IAS below 14000ft
265 Kts IAS above 14000ft
Military turbojets 265 Kts IASClimbing in holds 310 Kts IAS or less (jets)
-
8/6/2019 How to Fly a Holding Pattern
6/16
indicator (
HSI) : The Holding fix is located at the centre of the DG or your HSI, and you are at the bottom of the instrument
heading toward the fix. Now locate the radial or bearing from the holding fix on the HSI: this is the inbound leg.Then visualize the racetrack according to the type of turns.
2-Types of entry:
Once we figured out where is this holding pattern, let talk about types of entry.
There are three types of entry, depending on your location when approaching the holding fix.
Divide the airspace in two parts along the inbound leg of the hold (1), then at right angle starting from the fix
(2). Lastly, tilt the line N2, 20 degrees down to the side of the holding pattern (3). You end up creating four
sectors (actually three) which give you the type of entries required.
-
8/6/2019 How to Fly a Holding Pattern
7/16
Direct Entry
-
8/6/2019 How to Fly a Holding Pattern
8/16
Parallel Entry
-
8/6/2019 How to Fly a Holding Pattern
9/16
Teardrop Entry
Since we visualize the holding pattern directly on the DG or HSI, the entry method and the headings to followbecome straightforward.
-
8/6/2019 How to Fly a Holding Pattern
10/16
In our last example (a nonstandard holding
pattern on the 330 degrees radial), we would
have to fly a teardrop entry, i.e. fly direct to
the fix from the South with a 360 heading,
then upon passing the fix (the VOR flagchanges from TO to FROM), we fly the 360
degrees heading (330 degrees PLUS 30
degrees ) and start the timer for one minute,
then turn left (standard rate turn) to intercept
and track the 330 radial of YMX VOR and
enter the hold.
-
8/6/2019 How to Fly a Holding Pattern
11/16
Lets say we are heading from the West in a
090 heading. This time we have to perform a
direct entry, i.e. we fly direct to the fix with a
090 heading, then upon passing the fix (the
VOR/HSI flag changes from TO to FROM), we
turn outbound on the 330 heading with astandard rate left turn. When we level off the
turn, we start the timer for one minute, and
then we go. At the end of one minute (plus or
minus the wind correction), we start the turn to
intercept and track the 330 radial inbound
and enter the hold.
-
8/6/2019 How to Fly a Holding Pattern
12/16
Here we are flying direct the VOR from the
East on a 240 heading. Our position calls for a
parallel entry, i.e. we fly direct the VOR with a
240 heading, then upon passing the fix (the
VOR/HSI flag changes from TO to FROM), weturn right to a heading 330 so we fly parallel to
the inbound course and start the timer for one
minute, then turn right (notice the difference
with the other type of entries) to intercept
and track inbound the 330 radial and enter
the hold.
Practice a little bit using this method and avoid drawing anything on a piece of paper. When youre flying in
the clouds your eyes should be on the instruments and seldom elsewhere!The trick is to VISUALIZEand PRACTICE.
3-Flying the holdNow its time to relax and let the autopilot do the job No just kidding, unless you fly one of these all-
computerized FMS machines that can do a Hold with a simple couple of keystrokes
-
8/6/2019 How to Fly a Holding Pattern
13/16
Once youve entered the Hold either way, you should be flying inbound the fix, tracking the VOR radial or
the NDB inbound course. You have to remember that a Hold is (in most cases) one minute long on the
inbound leg when below 14000feet or 1 minute when above 14000feet.
In order to reach that goal, and keep the ATC happy, we have to account for the wind. We will have to
compensate for headwind or tailwind by adjusting the outbound leg so the inbound leg is one minute or
one minute long.
When to start the timer?
For the inbound leg:
- As soon as you roll out from the inbound turn out OR intercept the inbound track, start the timer.
- When abeam the station at a VOR (the flag changes from TO to FROM) or a NDB (The needle flips from
the nose to the tail), stop the timer.
For the outbound leg:
-If the Holding fix is a VOR, when the TO-FROM indicator changes from FROM to TO, start the timer.
-If the holding fix is a NDB, when the needle points (with no wind) 90 degrees to the left or the right, i.e.
points to the wingtip, start the timer.
Turns are never timed, as they are standard rate turns.
You end the outbound time and start the inbound turn depending on the wind.
Adjusting the outbound leg.
If you dont know the winds aloft, fly the first pattern with a one minute outbound leg. Then measure the
time required to fly the inbound leg. For the second pattern, fly the outbound leg by adding or
substracting to one minute the difference between one minute and the time you flew the inbound leg.
Confused? An example will make it clear.
If the first outbound leg was 1 minute and the inbound leg took30 seconds, fly the next outbound
leg for 1 minute (60sec+30sec). (Headwind on the outbound leg, see the example below)
-
8/6/2019 How to Fly a Holding Pattern
14/16
If the first outbound leg was 1 minute and the inbound leg took1 minute and 15 seconds, fly the
next outbound leg for 45 seconds (60sec-15sec). (Headwind on the inbound leg)
Wind correction and Crosswind.
In a perfect world, there would no be crosswinds. But in real world (and even in simulation!) the crosswind is
something to be accounted for in a Hold.
Since both turns are standard rate, a crosswind causes the downwind turn to have a larger radius than the
upwind turn.
So the racetrack looks now more an egg shaped oval when crosswind is involved.
Now you have your answer ready when ATC calls in and ask the reason for the strange pattern youre drawing
on his scope!
-
8/6/2019 How to Fly a Holding Pattern
15/16
So obviously one have to fly the pattern while correcting for the wind.
The rule of thumb is to double the inbound leg wind correction angle on the outbound leg.
On the inbound leg, track the VOR radial and use whatever correction angle is needed to compensate the
drift and stay on course. Note the wind correction angle you are using.
So if you had to fly a 100 degrees heading (1) to stay on course inbound of a 270 radial (90+10 degrees wind
correction angle), in order to compensate for a crosswind coming from your right, you will fly a 250 degrees
heading (2) outbound (270-(2*10 degrees)) for the outbound leg.
4-Exiting the holdAfter a couple of turns, the ATC will probably release you from the hold (at last!)
But if youre five minutes from the EFC time, ask the ATC for a clearance (hes probably asleep), as you need
to know what to do next. He will then clear you for another Hold (oh nooo!), have you descend to another
altitude and hold(Shuttle Hold, more on that later), or give you radar vectors to proceed direct to the
approach.
-
8/6/2019 How to Fly a Holding Pattern
16/16
In case of radio communication failure, squawk 7600, hold until reaching the EFC time, then proceed as filed,
i.e. fly the full approach or proceed to the next waypoint on your route.
In all cases, try and adjust your speed so you leave the Holding pattern as close as possible as the EFC timeyouve been given in the holding clearance.
Shuttle procedure.
A shuttle procedure is a maneuver involving a descent or climb in a pattern similar to a holding pattern. It is
used on instrument procedures located in mountainous areas, or for certain types of missed approaches, or
when ATC clears a plane, located below in a stack, for the approach and instructs the planes holding in the
same airspace to descend one step further.
The maneuver is flown exactly the same as a holding pattern, except that descent will occur within the
inbound or the outbound leg. In order to prevent the airplane from exiting the protected airspace, speed is
restricted to 200kts IAS.
Enjoy the flight!
Jacques Zahar
ICAO CPL/ multi/IR flight instructor
The material exposed here is copyrighted and should not be used without written permission from the author.For comments or suggestions write to Jacques Zahar.