I ALWAYS park my SR22 with the flaps at 10°/t.o. position.
Reason: The passengers don’t step on the edge of the flap when embarking. The flap linkage is exactly below that edge close to the wing walk aswell.
The general problem here is that people put way too much faith into those “checklists”.
There are two kinds of checklists. 1) manufactures prepared and subsequently FAA/CAA approved, 2) operator prepared
The latter – at least in flightschool, flying clubs, etc., are usually terrible, prepared by some bloke who wanted to share his ideas about how he thinks the aircraft is to be operated. Zero consistency of course and loads of useless stuff on there, with sometimes dangerous omissions, etc.
The former are usually a bit better, but still, people put way too much faith into them. After all, even those are prepared by human beings, who might take good decisions and bad decisions. Also, often there are no definite truths about what is exactly right or wrong when operating an aircraft.
Hence, no wonder checklists are totally inconsistent regarding checking flaps on pre-flight, even on identical models. There are many other points, for example: mixture lean during taxy yes or no? Check magnet grounding before shutoff yes no? when to switch off carb-heat? How many RPMs for the runup? Do an idle check after run-up? The list goes on forever.
I consider those manufacturer checklists nothing more than a little aid in operating the aircraft when you are completely new to it. But after that, everone needs to develop his own routine anyway, based on his knowledge about piloting and aircraft technology.
In the case of flaps, I ask myself:
-do I need to lower them in order to see the hardware better?
-do I want to see it better?
-do I want to check flap operation before I take-off? Are flaps vital for my next flight?
-do I have to save the battery?
and then decide what I do.
There are two kinds of checklists. 1) manufactures prepared and subsequently FAA/CAA approved, 2) operator prepared
Plus the generic ones e.g. sold by pilot shops. Usually useless unless modified.
Exactly, for a private operator the FOM or POH are not exactly “bibles”. I modify the procedures accordung to my needs and EXPERIENCES.
One othe example: While the SR22 POH gives 88 KIAS as the best glide speed many tests have shown that 95-100 works better in mosts cases.
Alexis wrote:
While the SR22 POH gives 88 KIAS as the best glide speed many tests have shown that 95-100 works better in mosts cases.
As long as you don’t call it “best glide speed”, you can use any speed that works for you as an engine out speed.
One thing worth considering when parking the aircraft with the flaps not fully retracted is that, depending on type, it exposes parts of the control linkage and wing openings to the elements that are normally covered. So if the aircraft lives outside, this lead to corrosion, water in places it would not normally get to (sometimes drain holes are in places that only work in a particular position) and other problems.
Not that this is always taken into account in the manufacturer’s manuals – the widespread, POH-supported practice to “secure” the ailerons and stabilator in Piper PA28 aircraft by pulling the yoke back with the seatbelt can lead to water accumulating in the stabilator. It will easily splash out when the yoke goes forward, but if water would be good inside the stabilator the manufacturer would fill the with water at the factory. And good luck if it freezes…
Personally – I think some of the checks, whether by manufacturer recommendations, are silly. It is good airmanship to inspect (a) stuff that can easily be checked, and (b) stuff that kill you when broken and (c) stuff that is likely to go wrong.
Everything else is unneccessary. And of course, prior maintenance means everything is (c) – likely wrong – and requires a completely different level of checking.
boscomantico wrote:
I consider those manufacturer checklists nothing more than a little aid…
I consider manufacturers checklists as their insurance against liability claims. Especially for complex aircraft these lists can be so long that it is virtually impossible to go through them without having to top up the tanks again before actually taking off…
Therefore the abbreviated checklists are an absolute necessity for everyday flying. In case of commercial flying schools and commercial operations (which I do both) these abbreviated checklists are part of the operating/training manuals and require approval from the authority. But consequently also adherence by the pilots. So even if I think I know it better (of course I always do) I will go by the piece of paper the school/company hands me out to work with. So if the school tells me to keep the flaps of a low wing aircraft fully extended after landing (luckily they don’t) I will do that – knowing that the next one who will taxi like that throug grass or potholes will most probably damage them. But at least no one will have stepped upon those flaps…
what_next wrote:
The things I fly at work have hydraulically operated flaps which require an engine running in order to move. Therefore one is supposed not to raise them fully after landing but to the first stage only so that they can be inspected (and cleaned) post and pre flight. So when one sees a light jet parked with the flaps halfway down this is not because the crew is too stupid or lazy to read their checklists. If the speeds brakes still stick out however it’s a little embarrasing for the crew (or oneself in some cases…).
Our are electric but you still leave in TO/APR setting. And as to speedbrakes….cough…..never done that…..!
It’s always my first item when I start the preflight – lower flaps to full extension and watch them go out, IOW check for symmetrical and proper deployment. Then during the walkaround visually and manually inspect the linkages, rollers and roller guides (not sure that’s the correct term, though).
