what my instructor has me doing, is that on the ground, list comes out; in the air, mnemonics come out.
Please pardon me for stirring this pot more, but...
I see the overlying concept here, though it is a fine line between basic flying instruction, and resulting correct technique, type specific operating "to do's", and a checklist. Though there is cross over, which is an obvious safety requirement, each are still distinct from the other. Where do mnemonics (memory only items) fit into this?
To me the pilot actions associated with HASELL, GERTRUDE, FREDA, and all those other memorable women are basic flying instruction, and definitely not aircraft type specific. As such, though they might appear on a checklist developed by a flying school, or operator, it would probably more just co-incidental that they would appear in an aircraft manufacturer's type specific checklist. As such, I do not believe that anyone could claim (other than by a confirmation by cross checking both) that any mnemonic replaces the manufacturer's checklist.
Using the Flight Manual as a reference (and I have the C-172S one open now), the "to do" list section would equate best to the Amplified Procedures section. It tells you
how to operate the [possibly] unique systems of the aircraft, which are type specific. Of course, there can be huge overlap to other similar types.
Now, back to the "checklist". The C-172S FM I have, as well as many others I have checked, says under Emergency Procedures Checklist:
Procedures in the Emergency Procedures Checklist portion of this section shown in bold faced type are immediate action items, which should be committed to memory.
The intent that Cessna have every pilot memorize certain checklist items is obvious. Cessna obviously feels that those items are memorize-able, and the pilot does have time to safely read the rest - in flight. If a mnemonic covers it (without overlooking any type specific item), that's great. But, does it for the next type you fly too?
It can be reasonably interpreted that Cessna does not intend that the pilot memorize the rest of the checklist, but they do still intend that the pilot use it, so reading it - in flight - is obviously intended. So the manufacturer has provided it, as they are required to do by regulation.
Is the pilot required to use it?
Quoting form the prevailing Canadian regulation:
602.60 (1) No person shall conduct a take-off in a power-driven aircraft, other than an ultra-light aeroplane, unless the following operational and emergency equipment is carried on board:
(a) a checklist or placards that enable the aircraft to be operated in accordance with the limitations specified in the aircraft flight manual, aircraft operating manual, pilot operating handbook or any equivalent document provided by the manufacturer;
...........
(2) A checklist or placards referred to in paragraph (1)(a) shall enable the aircraft to be operated in normal, abnormal and emergency conditions and shall include
(a) a pre-start check;
(b) a pre-take-off check;
(c) a post-take-off check;
(d) a pre-landing check; and
(e) emergency procedures.
(3) Emergency procedures referred to in paragraph (2)(e) shall include
(a) emergency operation of fuel, hydraulic, electrical and mechanical systems, where applicable;
(b) emergency operation of instruments and controls, where applicable;
(c) engine inoperative procedures; and
(d) any other procedure that is necessary for aviation safety.
(4) Checks and emergency procedures referred to in subsections (2) and (3) shall be performed and followed where they are applicable.
So, the pilot could argue that he/she had memorized the whole thing, and I suppose that a demonstration of type specific "total recall" to the enforcement inspector might get you through. But, if you're being asked, it's probably because something has gone wrong. If you are caught not referring to the checklist, and doing it wrong, I can imagine being cited for violating this (or your local equivalent) regulation in extreme circumstances.
Yes, I am being extreme here, and I often work from my "memorized" checklist when flying certain very familiar types, (though I pull out the paper every time in the Caravan or Navajo). But, a new pilot falling into this casual "trap" early in his/her career, will for certain require an adjustment to the
right way of doing things, when flying in the "more professional" environment. Out will come the paper - every time- why not practice it now? It dissapoints me to think that instructors are condoning, or worse, teaching, this casual attitude toward reading the manufacturer's paper checklist in flight.