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6/17/21 

AIM 

(5) 

Some RNAV systems compute the 

holding pattern based on the aircraft’s altitude and 
speed at a point prior to entering the hold. If the 
indicated airspeed is not reduced to comply with the 
maximum holding speed before this point, the 
computed pattern may exceed the protected airspace. 
Loading or executing a holding pattern may result in 
the speed and time limits applicable to the aircraft’s 
current altitude being used to define the holding 
pattern for RNAV lateral guidance. This may result in 
an incorrect hold being flown by the RNAV system. 
For example, entering or executing the holding 
pattern above 14,000 feet when intending to hold 
below 14,000 feet may result in applying 1 

½

  minute 

timing below 14,000 feet. 

NOTE

 

Some systems permit the pilot to modify leg time of  holding 
patterns defined in the navigation database; for example, 
a hold

in

lieu of procedure turn. In most RNAV systems, 

the holding pattern time remains at the pilot

modified time 

and will not revert back to the coded time if the aircraft 
descends to a lower altitude where a shorter time interval 
applies. 

(b) 

RNAV systems are not able to alert the 

pilot for excursions outside of holding pattern 
protected airspace since the dimensions of this 
airspace are not included in the navigation database. 
In addition, the dimensions of holding pattern 
protected airspace vary with altitude for a charted 
holding pattern, even when the hold is used for the 
same application. Close adherence to the pilot actions 
described in this section reduce the likelihood of 
exceeding the boundary of holding pattern protected 
airspace when using RNAV lateral guidance to 
conduct holding. 

(c) 

Holding patterns may be stored in the 

RNAV system’s navigation database and include 
coding with parameters defining how the RNAV 
system will conduct the hold. For example, coding 
will determine whether holding is conducted to 
manual termination (HM), continued holding until 
the aircraft reaches a specified altitude (HA), or 
holding is conducted until the holding fix is crossed 
the first time after entry (HF). Some systems do not 
store all holding patterns, and may only store patterns 
associated with missed approaches and hold

in

lieu 

of procedure turn (HILPT). Some store all holding as 
standard patterns and require pilot action to conduct 
non

standard holding (left turns). 

(1) 

Pilots are cautioned that multiple 

holding patterns may be established at the same fix. 
These holding patterns may differ in respect to turn 
directions and leg lengths depending on their 
application as an en route holding pattern, a holding 
pattern charted on a SID or STAR, or when used on 
an instrument approach procedure. Many RNAV 
systems limit the database coding at a particular fix to 
a single holding pattern definition. Pilots extracting 
the holding pattern from the navigation database are 
responsible for confirming that the holding pattern 
conforms to the assigned charted holding pattern in 
terms of turn direction, speed limit, timing, and 
distance. 

(2) 

If ATC assigns holding that is not 

charted, then the pilot is responsible for programming 
the RNAV system with the assigned holding course, 
turn direction, speed limit, leg length, or leg time. 

(3) 

Changes made after the initial execu-

tion may not apply until the next circuit of the holding 
pattern if the aircraft is in close proximity to the 
holding fix. 

8.  Pilot Action.

 The following actions are 

recommended to ensure that the aircraft remains 
within holding protected airspace when holding is 
performed using either conventional NAVAID 
guidance or when using RNAV lateral guidance. 

(a) 

Speed. When ATC furnishes advance 

notice of holding, start speed reduction to be at or 
below the maximum holding speed allowed at least 3 
minutes prior to crossing the holding fix. If advance 
notice by ATC is not provided, begin speed reduction 
as expeditiously as practical. It is acceptable to allow 
RNAV systems to determine an appropriate decelera-
tion point prior to the holding fix and to manage the 
speed reduction to the RNAV computed holding 
speed. If the pilot does not permit the RNAV system 
to manage the deceleration from the computed point, 
the actual hold pattern size at holding entry may differ 
from the holding pattern size computed by the RNAV 
system. 

(1) 

Aircraft are expected to enter holding at 

or below the maximum holding speed established in 
paragraph 5

3

8 j 2(a) or the charted maximum 

holding speed. 

[a] 

All fixed wing aircraft conducting 

holding should fly at speeds at or above 90 KIAS to 
minimize the influence of wind drift. 

En Route Procedures 

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