I always heard full flaps approach for short field landings (in my case means 40 degrees in my Cessna 182P).
But saw a training video saying 20 degrees gives you the lowest stall speed without the additional drag of 40 so you dont need to come with as much power.

What are your thoughts on this?

According to my POH
Flaps 20 = 59mph CAS Stall speed
Flaps 40 = 57mph CAS Stall speed.

So seems to be the POH doesnt agree with this theory.

I use full flaps in all cases except when it's super gusty from one side or the other , since I usually depart with half flap, if I suspect a go around may be in order I will use half flap so I am already set for departure if need be. Go out and land no flaps, one notch two notch ect and see what you like best and what's gives you the result you want. Sounds like you analyze this stuff to death. Go out and fly the airplane with different flap settings. The slower you touchdown the sooner you will stop..... Full flaps!

I've been involved in a few airplane development projects and in my experience if the flaps were designed by anyone that knows what they are doing (Cessna knows what they are doing) then the higher the flap angle the higher the CLmax of the airplane and the lower the stall speed. That is usually the case up to until about 40-45 degrees of flaps. The higher flap angles typically have more drag so the overall lift to drag ratio (L/D) is pretty low at landing flaps. For a short and precise landing that is a good characteristic of the flaps. You will end up as slow as possible on touchdown and you will also be able to land in the spot you pick (no floating).

you want the lower energy and more drag. don't you

I agree with the above post. Flaps up to 40 degrees should offer progressively more lift (and more drag) in something conservatively designed like a 182. Extreme flap settings on some super STOL planes MAY actually reduce CLmax slightly, but offer crazy amounts of drag for elevator steep approached.

So for a short landing, full flaps and minimum safe speed above stall (I'll leave that one up to you). You will have to carry power for a normal glide path because you will be well behind the power curve on the drag bucket. Pull out the power, and plop where you are instead of floating down the runway like you may with 20 degrees flaps.

Now depending on your skill and comfort level, 20 and 40 degrees may not make that huge a difference on the minimum speed you can come in it at, but more flap is more drag for stopping faster and floating less.

I have a 182B and cannot remember landing with less than 30 deg. 19 out of 20 times it is with 40 deg. I have not landed without flaps in 15 years. Maybe it is something I should try.

Tim

Having learned to fly in a plane with no flaps, 7ECA, many plans with flaps and gliders with spoilers I find that they all are good if you stay in practice. I often land my plane with none, full or anything in between. Keeps on sharp.

However, if I could have only one, I wish I could have split bottom and top spoilers.

Dane

low rider wrote:I use full flaps in all cases except when it's super gusty from one side or the other , since I usually depart with half flap, if I suspect a go around may be in order I will use half flap so I am already set for departure if need be. Go out and land no flaps, one notch two notch ect and see what you like best and what's gives you the result you want. Sounds like you analyze this stuff to death. Go out and fly the airplane with different flap settings. The slower you touchdown the sooner you will stop..... Full flaps!

I was going to say the same thing, you saved me the trouble! That works on my S-7S anyway real well.

Depends somewhat if you ever slip it down to short final. In a 170B for instance, full flaps are known to wash out the rudder in a slip. I believe that flaps 20 is the most that a 170B is allowed in a slip. This may not technically apply to your plane, but you might want to familiarize yourself with rudder effectiveness in a slip with full flaps (cautiously!!)

Also- If you want to dump lift fast once you are down, it stands to reason that dumping flaps 40 is going to dissipate your lift more effectively that dumping flaps 20.

-DP

denalipilot wrote:Depends somewhat if you ever slip it down to short final. In a 170B for instance, full flaps are known to wash out the rudder in a slip. I believe that flaps 20 is the most that a 170B is allowed in a slip. This may not technically apply to your plane, but you might want to familiarize yourself with rudder effectiveness in a slip with full flaps (cautiously!!)

Also- If you want to dump lift fast once you are down, it stands to reason that dumping flaps 40 is going to dissipate your lift more effectively that dumping flaps 20.

-DP

I think you mean it will wash out the horizontal stabilizer and elevator, causing a sudden pitch downward. I've done it once and that was enough.

robw56 wrote:

denalipilot wrote:Depends somewhat if you ever slip it down to short final. In a 170B for instance, full flaps are known to wash out the rudder in a slip. I believe that flaps 20 is the most that a 170B is allowed in a slip. This may not technically apply to your plane, but you might want to familiarize yourself with rudder effectiveness in a slip with full flaps (cautiously!!)

Also- If you want to dump lift fast once you are down, it stands to reason that dumping flaps 40 is going to dissipate your lift more effectively than dumping flaps 20.

-DP

I think you mean it will wash out the horizontal stabilizer and elevator, causing a sudden pitch downward. I've done it once and that was enough.

Oops. I believe you're correct. Thanks for the correction. I just knew there was a good reason not to do it!

I usually use 20 in my 182j for a few reasons:
1) You can go around with 20 if necessary.
2) You can see better.
3) You can brake better (I have the electric lever with no notches so I have to hold the flap switch to move them)
4) You can land in crosswinds better.
5) I don't like the nose up attitude of full flaps.
6) You'll still land in less distance than you'll use departing.
I do sometimes approach an airport with an obstacle with 20 and then upon clearing it, I slam full flaps while pushing the nose over as I pull power off. As I get into ground effect, I'll flare hard and add a burst of power. It seems to work.

I'll vote with the guys recommending practicing all flap settings including clean after my last flight review, here's how it went:

I was 95% done with the review after having done the oral the previous day and an hour of stalls, unusual attitudes and some hood time. All I had to do was land one last time. This is when the female instructor pulled power off halfway along the downwind. For some dumb reason, I glided past the numbers before turning towards the runway, then barely made it to the end of the runway--but I made it. Now muscle memory took over after countless landings with flaps and I held it at 65, pushed the 3 bladed simitar full forward and started my flare. At this point, both levitators quit working at about 3 feet off the runway and we sunk like a stone hitting the tarmac so hard it knocked the taste out of my mouth. The stall horn blared, stuttered on impact and blared again as we launched. Now I was jarred to my senses and did my job not to hit a second time but the poor horrer-stricken instructor and myself were both wondering whether the wheels were still attached. The tough Cessna gear checked out fine and all I had was a dislocated bung-hole and a shattered ego. The instructor thought it was her fault but it wasn't. It was mine for not knowing how to land my own plane without power and flaps. I've practiced a lot since then with various flap settings.

Gee.... I wonder why those Cessna engineers bothered to put in those 40 degrees of flaps?

Gump

agreed gump...i vote FF...easier on the gear and etc...most cessnas im around, 182,206's etc will allow u to get a pos rate of climb with FF if need be...

I've noticed some mention too high of a nose attitude when landing with full flaps.
Are you guys dragging it in?
When I want to land my 170B short (actually most of my landings are this way, except with x-wind), I stabilize on final with power off (or 1000 rpm or so to get to the glide slope) and full flaps trimmed for 60 mph or less (depending on GW). The plane settles on a 500 fpm steep descent and the nose stays pretty level with the horizon.
When close to the ground I round out and flare and the plane does a full stall landing at 3 point attitude at about 40 mph or less.
Roll out is about five hundred feet or less (sea level) with minimum braking.

Full flaps (48 degrees), 55 mph final approach speed and light braking before touchdown for the shortest (3-pointer) landing in my Maule MX-7-180.

GumpAir wrote:Gee.... I wonder why those Cessna engineers bothered to put in those 40 degrees of flaps?

Gump

I think it was so that even short guys like me can get diamond shape cuts on the forehead.

Tim

AKclimber wrote:I've noticed some mention too high of a nose attitude when landing with full flaps.
Are you guys dragging it in?
When I want to land my 170B short (actually most of my landings are this way, except with x-wind), I stabilize on final with power off (or 1000 rpm or so to get to the glide slope) and full flaps trimmed for 60 mph or less (depending on GW). The plane settles on a 500 fpm steep descent and the nose stays pretty level with the horizon.
When close to the ground I round out and flare and the plane does a full stall landing at 3 point attitude at about 40 mph or less.
Roll out is about five hundred feet or less (sea level) with minimum braking.

I think the 182's and 206's are so heavy the fowler flaps just squirt a lot of air on top of the stabilizer. It's actually a good thing if you need to plunk down like a parachuter but I prefer less flap, flatter transition, and gentle chirp where I have plenty of runway. The chord line follows your flap settings, right? Seems like it would have to thus narrowing the gap between it and your stall speed angle of attack with every notch of flap.

Nosedragger wrote:

AKclimber wrote:I've noticed some mention too high of a nose attitude when landing with full flaps.
Are you guys dragging it in?
When I want to land my 170B short (actually most of my landings are this way, except with x-wind), I stabilize on final with power off (or 1000 rpm or so to get to the glide slope) and full flaps trimmed for 60 mph or less (depending on GW). The plane settles on a 500 fpm steep descent and the nose stays pretty level with the horizon.
When close to the ground I round out and flare and the plane does a full stall landing at 3 point attitude at about 40 mph or less.
Roll out is about five hundred feet or less (sea level) with minimum braking.

I think the 182's and 206's are so heavy the fowler flaps just squirt a lot of air on top of the stabilizer. It's actually a good thing if you need to plunk down like a parachuter but I prefer less flap, flatter transition, and gentle chirp where I have plenty of runway. The chord line follows your flap settings, right? Seems like it would have to thus narrowing the gap between it and your stall speed angle of attack with every notch of flap.

Do you meen the 182's from 1962 and later. My 182B is as light as a feather on the controles, full flaps and trimmed way back.

Tim

qmdv wrote:Do you meen the 182's from 1962 and later. My 182B is as light as a feather on the controles, full flaps and trimmed way back. Tim

Hmmmm, didn't we just have this discussion about trimable horizontals in the Cessnas, and what makes the older 182's (and 180/185) such sweet flying airplanes?

Gump