Aircraft Operations. Volume II - Construction of Visual and Instrument ...

Part I — Section 4, Chapter 3 I-4-3-7
c) indicated airspeed (IAS): the highest procedural speed category for which the area is designed (see
Tables I-4-1-1 and I-4-1-2 of Section 4, Chapter 1);
d) true airspeed (TAS): the IAS in c) above adjusted for altitude a) and temperature b);
e) wind speed (w): omnidirectional for the specified altitude h;
w = (12 h + 87) km/h where h is in thousands of metres
w = (2 h + 47) kt where h is in thousands of feet or
provided adequate statistical data are available, the maximum 95 per cent probability omnidirectional wind may
be used (see Part II, Section 4, Chapter 1, 1.3.6, “Wind velocity”);
f) average achieved bank angle: 25° or the bank angle giving a turn rate of 3° per second, whichever is the lesser;
Note.— If the TAS is greater than 315 km/h (170 kt), the bank angle will always be 25°.
g) fix tolerance area: as appropriate to the type of facility or fix and type of entry; and
h) flight technical tolerance which is comprised of the following variables (see Figure I-4-3-8):
1) outbound timing tolerance of ±10 s;
2) pilot reaction time of 0 to + 6 s;
3) establishment of bank angle, + 5 s; and
4) heading tolerance ± 5°.
3.6.3 Operational assumptions
The operational assumptions associated with procedure design criteria for racetrack and reversal procedures are:
a) start of outbound timing — racetrack procedures:
1) for racetrack procedures using a facility — outbound timing starts from abeam the facility or on attaining
the appropriate outbound heading, whichever comes later; and
2) for racetrack procedures using a fix — appropriate outbound timing starts from obtaining the outbound
heading;
b) outbound track adjustment — racetrack procedures. The outbound track for racetrack procedures will always
be adjusted to avoid crossing the nominal inbound track before the final turn; and
c) pilot correction for wind effects:
1) for racetrack procedures, the area should be calculated and drawn for the fastest aircraft category to be
accommodated. Although the area based on the slow speed (i.e. 165 km/h (90 kt)) aircraft in strong winds
may in some places be larger than the area so constructed, it is considered that the normal operational
adjustments made by pilots of such aircraft are such that the aircraft will be contained within the area; and
23/11/06