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evrose created the topic: LSALT - Depart into IMC - No-Instrument Approach
Regarding departures into IMC at an AD without an instrument approach. I believe we need to ensure we can return to the departure AD so long as there is no cloud below LSALT and vis of 8km. See AIP ENR 1.1 10.7.2.10. However the latest version of the IREX guide on page 225 states a vis of 5km? Is this in error? Or as it must be in VMC, then it reverts to the VMC criteria MOS 91 2.0.7(3)?
bobtait replied the topic: LSALT - Depart into IMC - No-Instrument Approach
In the case of considering a return to land at the departure aerodrome, the decision is made after actual observation of the ambient conditions just before take-off. This is not the same as flight planning into the destination aerodrome.
In the case of flight planning to an aerodrome that is not served by a published instrument approach, the alternate minima is considered to be LSALT for the last route segment plus 500 feet and visibility of 8 km. That allows for the GAF to be less than perfect.
However, when you do take-off from such an aerodrome, if your intention is to return in the event of an engine failure, the only requirement is for VMC to exist up to the route LSALT. That means the cloud base must not be below LSALT and the visibility must be not less than 5km to allow for a visual approach.
Since you will be sitting in the cockpit and observing the actual conditions, you don't have to commit to IMC unless you can be sure of a visual approach. CASR 91 MOS Chapter 15 para 15.03 (ii).