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Holding Pattern: Part 2

Fly it even with wind!



The part 2 of this "Traffic Pattern" article deals with the execution of the holding pattern taking into account the wind. Therefore knowing the wind forecast at the altitude you will most likely fly the hold is crucial.


I recommend the use of a computer apps to easily determine your ground speed and Wind Correction Angle (WCA) because you will need both to fly the holding pattern properly.


As a quick reminder (useless if you fly only small GA piston planes), the maximum holding speeds in the US are:

200 KIAS MHA (Minimum Holding Altitude) - 6,000 ft MSL

230 KIAS 6,001 ft - 14,000 ft MSL

265 KIAS 14,001 ft MSL and above

The regulated inbound timing is 1 minute unless the altitude is above 14,000 ft MSL and therefore the inbound timing changes to 1 minute and half.


All turns are executed at standard rate (3° per second, use your bank indicator which is most of time the first notch on the gauge).


 

Execute one of the three entry previously determined using the thumb method:


Direct entry: Intercept the inbound radial and fly direct towards the fix.


Parallel entry: Overhead the fix, turn on the outbound course for 1 minute. Then execute a 225° turn towards the holding pattern to intercept the inbound radial under an angle of 45° to join the inbound radial prior to reaching the fix.


Tear drop entry: Overhead the fix, turn 30°away from the outbound course (inside the holding pattern region) for 1 min and execute a 210° turn to join the inbound course.


Source: https://www.cfinotebook.net/notebook/maneuvers-and-procedures/instrument/aircraft-holding-procedures

 

No wind scenario (less likely to happen)

  • Determine the type of entry you will need to enter the holding pattern (please refer to the "Holding Pattern, Part 1: Nail your entry!" article),

  • Slow down to the holding pattern speed. I use 90 KTAS when I fly the Cessna Skyhawk and 120 KTAS in the Cessna Centurion.

  • When establish inbound the fix of the holding pattern, start to use the 5 T's:

  1. Turn: Start your first 180° turn (left or right as published for the hold) to join the outbound course.

  2. Time: start the chrono for a minute once you are abeam the fix (if it is a VOR, the abeam point is when the flag "From" switches to "To" or vice versa depending on your current OBS setting or when you have finished your 180° turn whichever occurs later.

  3. Twist: Turn the OBS knob to set the inbound course.

  4. Throttle: Adjust as required to keep your airspeed in the hold.

  5. Talk: You need to report to the ATC that you are in the hold. E.g. "SoCal approach, Skyhawk 415, entering the hold 3,000 ft, at 1500 zulu"

With wind scenario (more likely to happen)


Determine the Wind Correction Angle (WCA) for the inbound course.


Quick easiest way to calculate good approximation is to use the following method:


First determine the cross-wind. 10° angle between the plane and wind heading= 1/6 of wind speed 20° angle between the plane and wind heading = 2/6 of wind speed

30° angle between the plane and wind heading= 3/6 of wind speed

40° angle between the plane and wind heading= 4/6 of wind speed

50° angle between the plane and wind heading= 5/6 of wind speed 60° to 90° angle between the plane and wind heading= wind speed

WCA calculation.

Divide the cross-wind component calculated above by the number of NM per minute based on your True Air Speed (i.e. TAS/60).


Example: plane heading 360° with a TAS of 120 KTS / wind is 040° at 16 KTS

Angle between the plane and the wind is 040° so let's take 4/6 of the wind speed which gives around 11 KTS.

120 KTAS is 2 NM per minute so WCA= 11/2= 5.5° rounded to 6°.


Follow all the steps as described in the "No wind scenario" except that the inbound leg needs to be corrected with 1 time the WCA whereas the outbound leg needs to be corrected with 3 times the WCA.


Why 3 times the WCA for the outbound course?

Because you will have to correct the wind during the outbound leg (that's 1 time) and during the two 180° turns that you will have to execute for completing a full lap in the hold (so 1 time for the first 180° turn and another 1 time for the second 180° turn). Indeed, correcting the wind effects during a turn is not possible.

If executed properly, ending your 180° turn to join the inbound leg should put you right on the inbound radial.


The fuel in the sim is cheap, so practice, practice and practice again to be fully confident.

Have fun! :)


TIPAH

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