Can I slip with flaps?

Checkout_my_Six said:
that is dangerous....dude. :eek:
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I was being literal. Back when Usenet newsgroups were king for aviation forums, we used to discuss the Cessna 172 advisory (I think one or two here might remember). Some guy came out with a T-shirt with a very simple "Slips with Flaps" logo, I'm thinking more than 20 years ago. I bought one. I think I finally tossed it a year or so ago.
 
Kansas Flyer said:
As others have mentioned you can make a Cherokee drop like a rock slipping with full flaps. On the other hand my Cardinal's manual says not to do it with more than half flaps so check your POH.
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What year and Model Cardinal? I’m looking at a 1977 C177B POH right now and it says “Slips are permitted with any flap setting.”
 
I used to slip our 172N with flaps hard all the time doing kamikaze approaches into IAD. Exactly once I got the dreaded "oscillation". It was kind of interesting, but hardly severe. I'm yelling "there it is, there it is!" to my wife (also a pilot) but she has no clue that it was happening. It only took a slight relaxation of the rudder to make it stop.
 
mscard88 said:
I get the pitching motion in the flight school's 172N, no biggie. The flaps are limited to 30* in ours, small plate screwed under the flap handle to prevent going past 30*, I assume. Anyone know why that is? I keep meaning to ask the owner but never seem to get around to it.
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midlifeflyer said:
Is it a 180 HP 172N? If so, it was part of the STC and, if I recall correctly, related to the decrease in minimum full flap climb performance (a certification requirement) due to the increase in max gross weight.
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Midlifeflyer is correct about the reason for limiting the flap travel. I don't know how the Penn Yan conversion works, but with Air Plains it is two separate STCs. One is for the engine change only, and does not change the original 2300 lb gross weight. Once that is accomplished, the second STC physically limits the flap travel (in Air Plains' mod it's a stop nut in the flap linkage inside the wing). That increases the MGW of a 172M, N or P to 2550 lb; somewhat lower for earlier models.

We bought both STCs. The engine change was done, but to date we have not installed the flap limiter. So as of now I have 180 hp and 40 degrees of flap, and 2300 lb gross weight. Useful load is only 767 lb, but with the small 40 gallon fuel capacity it's tolerable. I like short fields and I have no friends, so at least for now, the stop nut will remain in my desk drawer.
 
luvflyin said:
What year and Model Cardinal? I’m looking at a 1977 C177B POH right now and it says “Slips are permitted with any flap setting.”
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The footer on his post says it is a 1968 C177.
 
flyingron said:
I used to slip our 172N with flaps hard all the time doing kamikaze approaches into IAD. Exactly once I got the dreaded "oscillation". It was kind of interesting, but hardly severe. I'm yelling "there it is, there it is!" to my wife (also a pilot) but she has no clue that it was happening. It only took a slight relaxation of the rudder to make it stop.
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When tower tells me to make a short approach, and I'm at a light weight, the only way to do it is to chop power, dump all 40 degrees of flap, and make a 180-degree slipping turn all the way down. I imagine those CFIs in the 172s at the hold-short line are crossing themselves as a 172 slips in with full flap. :p
 
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luvflyin said:
Where? I don’t see it
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Same place as all the other footer notes/quotes people have - bottom of the post, below the footer line, left side.

Can you see Jeff Jacobs (Pilawt) footer notes in post #50 immediately above?

If you don't see it, I wonder if it might have something to do with the browser you are using? That's just a guess as I am not tech savvy enough to know.
 
GRG55 said:
Same place as all the other footer notes/quotes people have - bottom of the post, below the footer line, left side.

Can you see Jeff Jacobs (Pilawt) footer notes in post #50 immediately above?

If you don't see it, I wonder if it might have something to do with the browser you are using? That's just a guess as I am not tech savvy enough to know.
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IPAD mini 4. The only thing I get below that line on anyone’s post is Display name:. Pilawts is Pilawt. Yours is Aztec Flyer.
 
luvflyin said:
IPAD mini 4. The only thing I get below that line on anyone’s post is Display name:. Pilawts is Pilawt. Yours is Aztec Flyer.
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Must have something to do with the browser settings. I am using an iPad as well. The footers are directly below the main body of the posts, in the main posting box, not in the small avatar/info box to the left of the post.
They are in a greyscale, not black text. Faint horizontal line separates the footer from the posted text above.

Someone tech savvy on here probably knows what to do. I'm not that well versed, unfortunately.
 
GRG55 said:
Must have something to do with the browser settings. I am using an iPad as well. The footers are directly below the main body of the posts, in the main posting box, not in the small avatar/info box to the left of the post.
They are in a greyscale, not black text. Faint horizontal line separates the footer from the posted text above.

Someone tech savvy on here probably knows what to do. I'm not that well versed, unfortunately.
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I get that grayscale there, but never anything other than ‘GRG55, 8 minutes ago.’ I’ll ask in another thread about it. Thanks for the info
 
GRG55 said:
Must have something to do with the browser settings. I am using an iPad as well. The footers are directly below the main body of the posts, in the main posting box, not in the small avatar/info box to the left of the post.
They are in a greyscale, not black text. Faint horizontal line separates the footer from the posted text above.

Someone tech savvy on here probably knows what to do. I'm not that well versed, unfortunately.
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Up in the top right of your screen, you should see the head and shoulders of a little man. Click on it and a menu should pop up. Select preferences. Once in the preferences menu, you will see the option "Show people's signatures with their messages." Make sure that is checked.
 
Hank S said:
(simply because slips are aerodynamically inefficient.)
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Propellers with more than one blade are aerodynamically inefficient, also. The more blades, the more inefficient. ;)

I would argue that slips are an exceedingly aerodynamically efficient technique that trades excess potential energy for decreased altitude without increasing airspeed.
 
Lachlan said:
Propellers with more than one blade are aerodynamically inefficient, also. The more blades, the more inefficient. ;)

I would argue that slips are an exceedingly aerodynamically efficient technique that trades excess potential energy for decreased altitude without increasing airspeed.
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I prefer to efficiently lose my altitude before final approach, when I can safely convert the extra potential energy into free kinetic energy, to reach my destination sooner. It takes so much time and fuel to climb to altitude, why throw it away with a slip? Recover it with a planned descent. A slip is just a way to say, Oops! I blew it, I'm too high.
 
Hank S said:
I prefer to efficiently lose my altitude before final approach, when I can safely convert the extra potential energy into free kinetic energy, to reach my destination sooner. It takes so much time and fuel to climb to altitude, why throw it away with a slip? Recover it with a planned descent. A slip is just a way to say, Oops! I blew it, I'm too high.
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That energy isn't free; you bought it with avgas. :) If you try flying into my home strip without slipping you'll be going around, or picking the trees at the far end of the runway out of your teeth because you wasted half the runway before your wheels touched the ground. Or you tried to drag it in too low, so you're picking the trees out of your teeth that you landed in on the near end of the field. A slip isn't a cover for a mistake. Not learning how to, or being unable to, is the mistake. ;)

*I know exactly what Hank means regarding his method of dissipating energy and landing without slips, but this is PoA, so we gots ta argue a little.
 
Pilawt said:
Midlifeflyer is correct about the reason for limiting the flap travel. I don't know how the Penn Yan conversion works, but with Air Plains it is two separate STCs. One is for the engine change only, and does not change the original 2300 lb gross weight. Once that is accomplished, the second STC physically limits the flap travel (in Air Plains' mod it's a stop nut in the flap linkage inside the wing). That increases the MGW of a 172M, N or P to 2550 lb; somewhat lower for earlier models.

We bought both STCs. The engine change was done, but to date we have not installed the flap limiter. So as of now I have 180 hp and 40 degrees of flap, and 2300 lb gross weight. Useful load is only 767 lb, but with the small 40 gallon fuel capacity it's tolerable. I like short fields and I have no friends, so at least for now, the stop nut will remain in my desk drawer.
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Thanks for the explanation, appreciate it. Good to know.
 
Hank S said:
A slip is just a way to say, Oops! I blew it, I'm too high.
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For most airplanes that have flaps, that may be true, but at bare minimum, a slip is still a tool to carry in the tool bag.

So you misjudged and are a little high? Why run off the end or perform an unnecessary go around if you can safely adjust with a slip?

It’s a pretty handy tool to have at your disposal if you ever have to make a real off airport, engine out landing.

If I’m doing a power off 180 or having to do a real engine out landing, I’d much rather find myself too high and needing to slip than a little low...
 
Fearless Tower said:
For most airplanes that have flaps, that may be true, but at bare minimum, a slip is still a tool to carry in the tool bag.

So you misjudged and are a little high? Why run off the end or perform an unnecessary go around if you can safely adjust with a slip?

It’s a pretty handy tool to have at your disposal if you ever have to make a real off airport, engine out landing.

If I’m doing a power off 180 or having to do a real engine out landing, I’d much rather find myself too high and needing to slip than a little low...
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Very good points. Calling a slip a way to fix a mistake is like calling pliers the tool for people who don't know how to use a box wrench. Can't always get a box wrench on a part, like a pipe, for example. ;) Having the pilot's tool bag full of skill AND luck is essential to a long, safe flying career.
 
Lachlan said:
That energy isn't free; you bought it with avgas.

Yep, that's why I don't want to throw it away with unnecessary drag.

:) If you try flying into my home strip without slipping you'll be going around, or picking the trees at the far end of the runway out of your teeth because you wasted half the runway before your wheels touched the ground. Or you tried to drag it in too low, so you're picking the trees out of your teeth that you landed in on the near end of the field.

I was based for seven years at an obstructed 3000' field, never had a problem and almost never slipped after training. But I can . . . .

A slip isn't a cover for a mistake.

Except when it is.
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Fearless Tower said:
For most airplanes that have flaps, that may be true, but at bare minimum, a slip is still a tool to carry in the tool bag.

So you misjudged and are a little high? Why run off the end or perform an unnecessary go around if you can safely adjust with a slip?

It’s a pretty handy tool to have at your disposal if you ever have to make a real off airport, engine out landing.

If I’m doing a power off 180 or having to do a real engine out landing, I’d much rather find myself too high and needing to slip than a little low...
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That!


Given enough flight hours a slip will save your bacon at some point.
 
I flew into the sport expo at Sebring a few years ago in a C-172C with 40 degree flaps. At the last minute the “tower” told me land on the pink spot (1st one) when I was all set up for the green spot. A nice slip (with all 40 degrees in) and a very nice chirp landing on the pink spot. It’s just another tool in the bag.
 
luvflyin said:
Ah. Different Wing and Stabilator although all the Stabilators got replaced a year or two later.
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Its still the original stabilator, they modified them with slots just behind the leading edge. Its a very nice flying plane, but we're looking forward to upgrading to 180 hp as its a dog when hot and heavy.
 
Flying into KSLC from the west tower will sometimes clear you to land while you are almost directly above the numbers, maybe 1500 AGL. Sure you can refuse and continue on to fly a downwind while they sequence in another 100 planes, or you can slip on in like a shuttle commander.

Personally, I enjoy slips to landing.

Oh, want to add on that a slip to landing was part of my ppl checkride.
 
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Hank S said:
A slip is just a way to say, Oops! I blew it, I'm too high.
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I teach slips to my students. Oh my, did again this morning in a 152. As has been pointed out, it's another tool, and definitely comes in handy knowing how to do one when when the fan quits up front. Plus they're fun!
 
Guess I’m too old. Didn’t know you needed a note from your doctor to do that


Sent from my iPad using Tapatalk
 
I'm still trying to get my head around how you can control a plane with full flaps if they "blank out" air over the tail.
 
Salty said:
I'm still trying to get my head around how you can control a plane with full flaps if they "blank out" air over the tail.
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Hint - they most likely do not.
 
Salty said:
I'm still trying to get my head around how you can control a plane with full flaps if they "blank out" air over the tail.
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If they do, it’s only momentary. The tail stalls, the nose falls through, and air begins to pass over the tail again...voila, tail is flying again....until it stalls again.
 

You’re that guy that tries hypermiling in traffic and refuses to use his brakes because coasting to a stop is free, right? ;)
 
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