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AIM

10/12/17

5

−3−25

En Route Procedures

outbound turns. An aircraft’s flight guidance system
may use reduced bank angles for all turns including
turns in holding, especially at higher altitudes, that
may result in exceeding holding protected airspace.
Use of a shallower bank angle will expand both the
width and length of the aircraft track, especially as
wind speed increases. If the flight guidance system’s
bank angle limit feature is pilot

−selectable, a

minimum 25 degree bank angle should be selected
regardless of altitude unless aircraft operating
limitations specify otherwise and the pilot advises
ATC.

(4)

Where a holding distance is published,

the turn from the outbound leg begins at the published
distance from the holding fix, thus establishing the

design turn point required to remain within protected
airspace. RNAV systems apply a database coded or
pilot

−entered leg distance as a maximum length of the

inbound

 leg to the holding fix. The RNAV system

then calculates a turn point from the outbound leg
required to achieve this inbound leg length. This often
results in an RNAV

−calculated turn point on the

outbound leg beyond the design turn point. (See
FIG 5

−3−8). With a strong headwind against the

outbound leg, RNAV systems may fly up to and
possibly beyond the limits of protected airspace
before turning inbound. (See FIG 5

−3−9.) This is

especially true at higher altitudes where wind speeds
are greater and ground speed results in a wider
holding pattern.

FIG 5

−3−8

RNAV Lateral Guidance and Holding – No Wind 

FIG 5

−3−9

RNAV Lateral Guidance and Holding – Effect of Wind

9/13/18

AIM