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extract from the Air Operators Certification Manual
7.23.2.5 Route Limitations
IFR departure routes should be considered in the context of engine failure/malfunction
procedures, with guidance in preferable courses of action, if any, to be followed by the
pilot. In VMC it may be preferable not to follow IFR departure tracks in which case other
procedures should be instituted in collaboration with Air Traffic Services.
RPT routes must be within ASETPA safety distance of a suitable landing area (SLA).
Procedures setting out specific route limitations must be provided.
‘ASETPA safety distance’ means the maximum still air distance travelled in 15 minutes at
the aeroplane’s normal cruise speed plus a glide to 1000 feet AGL. ASETPA safety
distances will be directly proportional to aircraft operating altitude. The 1000 feet is a
nominal SLA manoeuvring allowance.
CAAP 92.1 ‘Suitable landing area’ means an aerodrome that complies with CAAP 92-1. At night,
SLAs must either display runway lighting while the aircraft is within the ASETPA safety
distance or be equipped with reflectorised panels.