Why leave flaps down to secure airplane?

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My flight school has a Skycatcher and part of the securing checklist says to leave flaps down. I’ve seen 150’s and 152’s do this as well while parked on the ramp.

Why?
 
Could be for the school to save wear and tear on the flap motor. But if inclement weather is coming I don't think it would be a good idea.
 
maybe that's for all flights EXCEPT for the last one of the day?
 
I would guess for the next person to have easy inspection preflight without wear on the motor/battery.
edit: or maybe to encourage them to not skip that step
 
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The Skycatcher uses a reflexive system. You can pull the flap down even when the Johnson bar is in the "flaps up" position.
That implies that the flaps are a spring-return system. Such systems were used in many older airplanes, including Piper ragwings and Maules. Those flaps get banging up and down if the airplane is tied down with its tail to the wind, and damage ensues. If the flaps are left full-down, they cannot move.

I took a look at the 162 AFM. Here's what it says:

1735404858212.png

The flaps are returned to the "faired up position by air load and spring assist." Then it warns you that the flaps can get blown down by tailwinds.

If we go to Section 4, Amplified Procedures, as Cessna mentions there, we see stuff like this:

From the preflight instructions:

1735405121177.png

Then this:

1735405186029.png

And in Section 8:

1735405382335.png

Once again: Consult the POH or AFM for answers to your questions. The answers are very often there. This AFM I found, free, here:

https://www.northcoastair.com/documents/Cessna 162 POH.pdf
 
He mentioned other planes too, and if they're down already it could encourage some to actually look instead of skipping that step. I'm guilty lol.
The proper procedure is for the flaps to be up so that you can check the spring tension.
Once again: Consult the POH or AFM for answers to your questions. The answers are very often there.
Ah, but the POH still does not say to put the flaps down for parking/securing. If anything, it says that the correct procedure is for the flaps to be up (to facilitate the installation of gust locks).
 
Normal occurrence for aircraft that have "Johnson Bar Flap Control". Many will leave the flap up, subject to being blown by tailwinds to the down then up position, slam bang slam slam. Some will extend the flaps to the down and locked position when securing the aircraft. Others will use gust locks. Improper use or positioning of gust locks can damage the skin or twist the flap, aileron, or rudder.
 
IIRC the skycatcher flaps do not have up locks, so they might bang around in the breeze if left up. Before you go move the flap by hand to convince yourself, remember that this will slacken the cables. I believe the pulleys have guards on them to prevent the cables from hopping off, but do you feel lucky? Well, do ya?
 
If tied down outside, seems leaving the flaps down would be a really bad idea as it would give the wind a better grip on the plane. My club plane was in such a strong wind one storm the s-hook was compressed and pulled through the strut o-ring.

I had an instructor once not let me raise the flaps until I cleared the runway. His rationale was, when moving to retracts, you don't want to be on the runway when you accidentally retract the gear.
 
Before you go move the flap by hand to convince yourself, remember that this will slacken the cables. I believe the pulleys have guards on them to prevent the cables from hopping off, but do you feel lucky? Well, do ya?
The POH says moving the flap by hand is the correct procedure (post #15, “Deflect and check”).
 
The POH says moving the flap by hand is the correct procedure (post #15, “Deflect and check”).
I always took that to mean "deflect [with the Johnson bar] and check", but I'm willing to be wrong.
 
I always took that to mean "deflect [with the Johnson bar] and check", but I'm willing to be wrong.
A couple things point away from that. First, one cannot get a good check of the spring tension by yanking the Johnson bar. Second, a few steps before the above excerpt is the cabin section and one of the steps there is to put the flaps up.
 
Ah, but the POH still does not say to put the flaps down for parking/securing. If anything, it says that the correct procedure is for the flaps to be up (to facilitate the installation of gust locks).
Correct. But I bet the airplane came with gust locks that owners put into some cupboard and promptly forgot about. Since owners are famous for never reading the POH, they will do whatever it takes to stop flaps banging around instead of reading that book that Cessna paid so much to have written. From posts on POA, I get the impression that at least half of owners don't know what their POH says.

Of course, it doesn't help that Cessna POHs have grown from a dozen pages many decades ago to a book an inch and half thick now. I remember our 172Ms in the flight school: the 1974 models had a POH of maybe 60 pages, the 1976 model was maybe 150. Big jump, and it was due to lawsuits against Cessna because the owners hadn't been warned not to fly below stall speed or to stay out of cloud if not IFR certified. Stupid, basic training stuff.
IIRC the skycatcher flaps do not have up locks, so they might bang around in the breeze if left up. Before you go move the flap by hand to convince yourself, remember that this will slacken the cables. I believe the pulleys have guards on them to prevent the cables from hopping off, but do you feel lucky? Well, do ya?
The cables won't jump off the pulleys. The guards are much too close to allow that.

I did a bunch of work on a Maule M4. It had the spring-loaded flaps, and these had been beat up some in the wind. (In spite of all that, the cables never left the pulleys.) In the service manual I found a drawing and specs to manufacture an elegantly simple flaps-up locking device. When the cables started to pull, the device unlatched and let the flaps go down. When they went back up, it latched again. Didn't need the dual pull-pull cabling used in all the Cessnas using Fowler flaps.
 
Low wing, I always leave them down to make getting off/on easier. Also prevents passengers stepping on them.
 
I had an instructor once not let me raise the flaps until I cleared the runway. His rationale was, when moving to retracts, you don't want to be on the runway when you accidentally retract the gear.
That's what I teach.

Some airplanes have the gear switch where you might expect the flap switch. I owned a Bonanza for many years, and my procedure after landing was to exit the runway, then place my right hand on the flap switch and say, "flaps identified and retracted."
 
That implies that the flaps are a spring-return system. Such systems were used in many older airplanes, including Piper ragwings and Maules. Those flaps get banging up and down if the airplane is tied down with its tail to the wind, and damage ensues. If the flaps are left full-down, they cannot move.

I took a look at the 162 AFM. Here's what it says:

View attachment 136605

The flaps are returned to the "faired up position by air load and spring assist." Then it warns you that the flaps can get blown down by tailwinds.

If we go to Section 4, Amplified Procedures, as Cessna mentions there, we see stuff like this:

From the preflight instructions:

View attachment 136606

Then this:

View attachment 136607

And in Section 8:

View attachment 136609

Once again: Consult the POH or AFM for answers to your questions. The answers are very often there. This AFM I found, free, here:

https://www.northcoastair.com/documents/Cessna 162 POH.pdf
Thanks Dan!
 
My flight school has a Skycatcher and part of the securing checklist says to leave flaps down. I’ve seen 150’s and 152’s do this as well while parked on the ramp.

Why?
As the actual POH as posted by others does not say this, then I assume your flight school is using a modified, tailored checklist. Therefore the only real way to answer this question is to ask them. But if it's a typical flight school with a high turnover, it's possible nobody there remembers why they put that in there, and you'll just get uneducated guesses.
 
David Lee Roth, in 'Crazy From the Heat' (1997) said that the provision: "Absolutely no Brown M&Ms" included on page 40 of all Van Halen concert contracts was made to check if the venue had read the entire contract. A test to see if people paid attention to the details.
 
If tied down outside, seems leaving the flaps down would be a really bad idea as it would give the wind a better grip on the plane. My club plane was in such a strong wind one storm the s-hook was compressed and pulled through the strut o-ring.
Open S hooks should never be used to tie down aircraft. The flap position will not make a difference.
 
Open S hooks should never be used to tie down aircraft. The flap position will not make a difference.
What should be used? Is your statement about how chains should never be used?
 
After landing you raise the flaps when leaving the runway,why put them backdown when securing the airplane.
 
Some Navions (all the Rangemasters and a few retrofitted canopy models) tend to park with the flaps down because to board the aircraft, you have to put your foot in a hole at the fuselage side of the left flap.
 
The flap control between the seats in a Skycatcher looks a lot like a parking brake in many cars, replete with the thumb button for putting the handle down. Maybe people are mistaking the former for one of the latter.
P6270070-20170718-130058.JPG

P6270072-20170718-130112.JPG
 
What should be used? Is your statement about how chains should never be used?
Never use open S hooks on the end of ropes. Airplanes bounce in high winds, can create slack in the line and the S hook can release. I've watched aircraft tumble across a ramp with the rope in good condition with the S hook still in place. I've also seen "cheap" S hooks unbend.

I did not say anything about chains, although chains are good, but should have a "snubber" for everyday use. The chain protects against ultimate failure of the rope. At least one chain is required at some airports due to increased TSA requirement to "lock the airplane down". Nothing any serious thief with a "Master Key" can't get past.
 
I've never flown one and I've only seen a few... but, my friend owned three of them and kept them at a flight school. As others have mentioned, you can walk up and pull the flaps down by hand. Even though it's not in the POH, the standard procedure became to put the flaps down to stop them from flapping around in the wind.

https://www.flywingsofeagles.com/wp-content/uploads/2015/04/SkyCatcher-POH.pdf
In this POH it says if there's a strong tailwind, taxi with the flaps down to prevent them randomly blowing down, but advises to put them up before turning back into the wind.

It also recommends parking into the wind, and if you can't park into the wind, to place the flaps in the full down position.

I think Cessna wanted to get away from this plane as quickly as possible and didn't modify the POH for this type of thing, but flight schools did because they got tired of fixing flaps. You may remember Cessna destroyed all remaining planes in their inventory and even destroyed the brand new O-200 engines.
 
It makes no sense with electric flaps. Some manual flap planes use cables to deploy flaps and springs to retract, so any wind with an aft component will bounce the flaps.
 
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