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AIM

10/12/17

5−3−27

En Route Procedures

[b] When RNAV lateral guidance is used

in fixed wing airplanes, it is desirable to enter and

conduct holding at the lowest practical airspeed

consistent with the airplane’s recommended holding

speed to address the cumulative errors associated

with RNAV holding and increase the probability of

remaining within protected airspace. It is acceptable

to allow RNAV systems to determine a recommended

holding speed that is at or below the maximum

holding speed.

[c] Helicopter holding is based on a

minimum airspeed of 90 KIAS.

(2) Advise ATC immediately if unable to

comply with the maximum holding airspeed and

request an alternate clearance.

NOTE−

Speeds above the maximum or published holding speed

may be necessary due to turbulence, icing, etc. Exceeding

maximum holding airspeed may result in aircraft

excursions beyond the holding pattern protected airspace.

In a non−radar environment, the pilot should advise ATC

that they cannot accept the assigned hold.

(3) Ensure the RNAV system applies the

proper time and speed restrictions to a holding

pattern. This is especially critical when climbing or

descending to a holding pattern altitude where time

and speed restrictions are different than at the present

aircraft altitude.

(b) Bank Angle. For holding not involving

the use of RNAV lateral guidance, make all turns

during entry and while holding at:

(1) 3 degrees per second, or

(2) 30 degree bank angle, or

(3) 25 degree bank angle, provided a flight

director system is used.

NOTE−

Use whichever requires the least bank angle.

(4) When using RNAV lateral guidance to

conduct holding, it is acceptable to permit the RNAV

system to calculate the appropriate bank angle for the

outbound and inbound turns. Do not use flight

guidance system bank angle limiting functions of less

than 25 degrees unless the feature is not pilot−se-

lectable, required by the aircraft limitations, or its use

is necessary to comply with the aircraft’s minimum

maneuvering speed margins. If the bank angle must

be limited to less than 25 degrees, advise ATC that

additional area for holding is required.

(c) Compensate for wind effect primarily by

drift correction on the inbound and outbound legs.

When outbound, triple the inbound drift correction to

avoid major turning adjustments; for example, if

correcting left by 8 degrees when inbound, correct

right by 24 degrees when outbound.

(d) Determine entry turn from aircraft

heading upon arrival at the holding fix; 

+

/− 5 degrees

in heading is considered to be within allowable good

operating limits for determining entry. When using

RNAV lateral guidance for holding, it is permissible

to allow the system to compute the holding entry.

(e) RNAV lateral guidance may execute a

fly−by turn beginning at an excessively large distance

from the holding fix. Reducing speed to the

maximum holding speed at least 3 minutes prior to

reaching the holding fix and using the recommended

25 degree bank angle will reduce potential excursions

beyond protected airspace.

(f) When RNAV guidance is used for holding,

pilots should be prepared to intervene if the turn from

outbound leg to the inbound leg does not begin within

a reasonable distance of the charted leg length,

especially when holding is used as a course reversal

HILPT. Pilot intervention is not required when

holding in an ATC−assigned holding pattern that is

not charted. However, notify ATC when the outbound

leg length becomes excessive when RNAV guidance

is used for holding.

k. When holding at a fix and instructions are

received specifying the time of departure from the fix,

the pilot should adjust the aircraft’s flight path within

the limits of the established holding pattern in order

to leave the fix at the exact time specified. After

departing the holding fix, normal speed is to be

resumed with respect to other governing speed

requirements, such as terminal area speed limits,

specific ATC requests, etc. Where the fix is associated

with an instrument approach and timed approaches

are in effect, a procedure turn must not be executed

unless the pilot advises ATC, since aircraft holding

are expected to proceed inbound on final approach

directly from the holding pattern when approach

clearance is received.

9/13/18

AIM