Not another "slip" question.

MDeitch1976

MDeitch1976

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MattCanFly
This maybe another one of those post heavy discussions.

Earlier on in my flight training I had to go out with another instructor because mine was out for several days, and I wanted to fly. The newer instructor I went out with had asked if I had learned to do slips, to help with crosswind, and losing altitude. We discussed how to do them, but never did any of them that day. Back out with my normal instructor again.

While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled. More recently speaking with my instructor he says we can work on some slips. Confusion now?

Can I use slips in the check ride for crosswind correction on final? Can I use them if I need to lose some altitude on final in the check ride? Why do some people say not with flaps in use?

Matt
 
I was given the following specific task during my PP checkride. "Land the aircraft with flaps zero while slipping to maintain a normal descent rate."
 
The prohibition against slipping with flaps extended is make-model specific. RTFM.
 
The DPE would probably get someone for cross controlling in flight, as opposed to using it as a tool to land?
 
Wayne's saying there are (a number of) aircraft in which slips with flaps extended (or extended past a certain point) are not approved.

If your POH says so, or there's a placard... you have one. If not, fuggetaboutit. ;)

In other words... "Read The 'Fine' Manual" for your aircraft. :)
 
MDeitch1976 said:
This maybe another one of those post heavy discussions.

Earlier on in my flight training I had to go out with another instructor because mine was out for several days, and I wanted to fly. The newer instructor I went out with had asked if I had learned to do slips, to help with crosswind, and losing altitude. We discussed how to do them, but never did any of them that day. Back out with my normal instructor again.

While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled. More recently speaking with my instructor he says we can work on some slips. Confusion now?

Can I use slips in the check ride for crosswind correction on final? Can I use them if I need to lose some altitude on final in the check ride? Why do some people say not with flaps in use?

Matt
Click to expand...

You definitely can use slips for crosswind correction. My CFI asked the DPE one day while he was at the flight school giving another ride, and he said "slip or crab, as long as you can do it safely" or something along those lines. See the following as well.


Old Geek said:
I was given the following specific task during my PP checkride. "Land the aircraft with flaps zero while slipping to maintain a normal descent rate."
Click to expand...

MDeitch1976 said:
Hope I don't get that one.
Click to expand...

dmccormack said:
I slipped all the way down to a foot above the pavement during my final landing during my PP practical. I passed.
Click to expand...

My examiner chose to do the engine out right above the airport I diverted to on my XC. We were naturally high above it and he said, "show me a forward slip." So I came out of the 360 I was doing and slipped it hard. When I slowed up enough to dump in some flaps, he said, "Flaps broken." So I slipped it on down to about 10 feet above the 3000 foot runway and rounded out for a normalish (no engine, no flaps, super long hard slip...) landing. He commented that I could probably have kept in the slip a while longer, but I said that with the long runway and lack of a crosswind, there was no reason to slip it all the way down to the pavement. He agreed.
 
MDeitch1976 said:
RTFM?

I am in a Piper Sport LSA
Click to expand...

According to one of my CFIs, that came from the old Cessna 172s where you'd get this odd oscillation from the aerodynamic effects of slipping with flaps on the elevators. Not a problem in most any other airplane. Because I asked about it, we tried it out on our way to doing some maneuvers. Slowed up, dropped full flaps, and slipped it as hard as possible...no warbling at all. Not even a burble. This was in a Tecnam Eaglet. It definitely depends on the airplane, but apparently even the new 172s don't have the problem. Or at least it's not that bad.

Someone with more knowledge of the problem should definitely chime in though....
 
More correctly, I'm recommending that pilots read the flight manual for the aircraft they fly, as well as placards and markings that contain limitations. I'm not sure which M/M's have prohibitions, warnings, advisories, recommendations, suggestions, threats, veiled hints, :eek:'s or other admonitions regarding this particular activity, but the PIC should make it a priority to know that stuff.

denverpilot said:
Wayne's saying there are (a number of) aircraft in which slips with flaps extended (or extended past a certain point) are not approved.

If your POH says so, or there's a placard... you have one. If not, fuggetaboutit. ;)

In other words... "Read The 'Fine' Manual" for your aircraft. :)
Click to expand...
 
denverpilot said:
Wayne's saying there are (a number of) aircraft in which slips with flaps extended (or extended past a certain point) are not approved.

If your POH says so, or there's a placard... you have one. If not, fuggetaboutit. ;)

In other words... "Read The 'Fine' Manual" for your aircraft. :)
Click to expand...

The Eaglet was placarded "Avoid slips with flaps extended." We slipped with flaps extended...with no problem. Not sure if it's in the POH, but I'll try to take a look in the coming days and post back. Point is that some of the people who are used to seeing this in older Cessnas think it carries over to other airplanes as well. Just what I've heard. Feel free to tell me I'm spewing hogwash, though.
 
jpower said:
According to one of my CFIs, that came from the old Cessna 172s where you'd get this odd oscillation from the aerodynamic effects of slipping with flaps on the elevators. Not a problem in most any other airplane. Because I asked about it, we tried it out on our way to doing some maneuvers. Slowed up, dropped full flaps, and slipped it as hard as possible...no warbling at all. Not even a burble. This was in a Tecnam Eaglet. It definitely depends on the airplane, but apparently even the new 172s don't have the problem. Or at least it's not that bad.

Someone with more knowledge of the problem should definitely chime in though....
Click to expand...

I get it in mine occasionally.
 
It's true that some older Cessna 172's have the warning against slipping with flaps extended, but that should NOT keep you from using a light sideslip to correct for a crosswind (wing low method) or from practicing slips for that matter. In fact, the last time I checked, a careful reading of 61.87(c) and 61.87(d)(14) would indicate that a pre-solo should be at least marginally proficient (ie. done it more than once, and knows how to perform one reasonably safely, even if not perfect) in a slip toanding.
It's on your instructor's conscience how much proficiency he must demand in those areas of 61.87(d), but I figure with my students, if we get the fundamentals down really well in the first 10-12 hours, and the student really "gets" those basic maneuvers, they are well set for the rest of their flying. After all, no student is going to beat the Wright Bros. record for fastest solo flight, and you can still get pretty done in the 40-50 hour range with a 12-15 hour student solo.

Ryan
 
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wabower said:
More correctly, I'm recommending that pilots read the flight manual for the aircraft they fly, as well as placards and markings that contain limitations. I'm not sure which M/M's have prohibitions, warnings, advisories, recommendations, suggestions, threats, veiled hints, :eek:'s or other admonitions regarding this particular activity, but the PIC should make it a priority to know that stuff.
Click to expand...

Right. And we should all preflight.

However....

Many airplanes don't have the more recent 400 page Operating Handbooks.

Bottom line -- if you have flaps, you can slip. Just know what the effects may be. You can read about it in the POH. You won't find a "prohibition," however.
 
Hi. I'm a CFI and too often I see students/clients who are deathly afraid to slip because of the association with "crossing the controls" and spinning. There is a lot of misinformation/misunderstanding out there. Remember, in order to spin, you have to be stalled first. No stall, no spin. Otherwise, the plane is in a benign slip, dragging itself through the sky which may or may not be your goal. If your goal is to lose altitude in a hurry (fire? medical emergency?) then a full-on slip can really help you drop like a sack of potatoes. If your goal is to deal with a crosswind on landing, then a milder slip is required. How much aileron vs. rudder you use depends on what you are trying to do.

I've often thought that flight training books add to the confusion among pilots by dividing slips into "forward" and "side" slips... a slip is a slip, it just depends on degree. Once you learn to use the slip as a tool in your toolbox, you'll actually find them to be quite fun. The key to doing them safely is to always maintain a low angle of attack. And as other posters have mentioned, be sure you understand what if any limitations on flap usage during slips exist for your airplane. In the Cub, this isn't an issue because we don't have flaps. So slips during approach and landing are a routine part of flying for us. :goofy:
 
dmccormack said:
Right. And we should all preflight.

However....

Many airplanes don't have the more recent 400 page Operating Handbooks.

Bottom line -- if you have flaps, you can slip. Just know what the effects may be. You can read about it in the POH. You won't find a "prohibition," however.
Click to expand...

One of my training airplanes was placarded against it. That's how I heard about the "controversy". I asked my CFI what it meant. Although all of the planes were C172P, not all of them were placarded, which I thought was odd.
 
MDeitch1976 said:
While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled.
Click to expand...

You might suggest that the instructor read the sections on landing and slips in the "Airplane Flying Handbook" published by the FAA. (Page 8-10)
 
MDeitch1976 said:
This maybe another one of those post heavy discussions.

Earlier on in my flight training I had to go out with another instructor because mine was out for several days, and I wanted to fly. The newer instructor I went out with had asked if I had learned to do slips, to help with crosswind, and losing altitude. We discussed how to do them, but never did any of them that day. Back out with my normal instructor again.

While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled. More recently speaking with my instructor he says we can work on some slips. Confusion now?

Can I use slips in the check ride for crosswind correction on final? Can I use them if I need to lose some altitude on final in the check ride? Why do some people say not with flaps in use?

Matt
Click to expand...
Be careful springing surprises on an instructor. Your results might vary. Mine was a power off stall to a spin. My head still hurts when I think about it.
 
As Dan's been hinting, a placard that says "avoid slips with flaps extended" is NOT a prohibition.

It's not a prohibition unless it's in the limitations section and the word prohibited is used, to the best of my knowledge.
 
MDeitch1976 said:
While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled.
Click to expand...
Your instructor is wrong.

Can I use slips in the check ride for crosswind correction on final?
Click to expand...
Yes.
Can I use them if I need to lose some altitude on final in the check ride?
Click to expand...
Yes. In fact, you'll be required to do that at least once on the ride.

Why do some people say not with flaps in use?
Click to expand...
Because they are misapplying what they learned regarding slips with flaps extended in Cessna 172's. In 172's (and only in 172's), there is the possibility of having a pitch oscillation develop when slipping with flaps extended, so there is a placard in 172's (and only in 172's) suggesting that one avoid slipping with flaps extended. Regarding that, first, after God-knows-how-many slips in 172's with flaps extended I've never had it happen, and second, if it does happen, just kick it out of the slip and it will stop. But unless you're flying a 172, there is no issue about slipping with flaps, and even if you are flying a 172, you can slip with flaps just fine as long as you remember what to do if the oscillation starts.
 
Jaybird180 said:
One of my training airplanes was placarded against it. That's how I heard about the "controversy". I asked my CFI what it meant. Although all of the planes were C172P, not all of them were placarded, which I thought was odd.
Click to expand...
It would indeed, because that "avoid" placard is required for legal airworthiness in virtually all 172's. However, it says "avoid," not "prohibited" or "restricted" so it is merely cautionary.
 
Jaybird180 said:
One of my training airplanes was placarded against it. That's how I heard about the "controversy". I asked my CFI what it meant. Although all of the planes were C172P, not all of them were placarded, which I thought was odd.
Click to expand...

The placard applies only to the 172 through to halfway through the 172N model. Not the P at all that I can see.

A quote from the TCDS:

D. On flap handle, Models 172 through 172E
(1) "Flaps - Pull to extend
Takeoff Retract 0
1st notch 10
Landing 0 - 40
(2) "Avoid slips with flaps down."
E. Near flap indicator Models 172F (electric flaps) through 17271034, excluding 17270050)
"Avoid slips with flaps extended."


I'd like to know what changed at serial number 71035 to make the placard unnecessary. I can't see any control surface movement changes.

The TCDS for anyone who wants to figure it out:
http://www.airweb.faa.gov/Regulator...feec0eb8625796d0069d3a9/$FILE/3A12 Rev 82.pdf


Dan
 
TMetzinger said:
As Dan's been hinting, a placard that says "avoid slips with flaps extended" is NOT a prohibition.

It's not a prohibition unless it's in the limitations section and the word prohibited is used, to the best of my knowledge.
Click to expand...

I did it last night. Though it was dark and I didn't see the placard until later when I turned on my flashlight.
 
Ron Levy said:
It would indeed, because that "avoid" placard is required for legal airworthiness in virtually all 172's. However, it says "avoid," not "prohibited" or "restricted" so it is merely cautionary.
Click to expand...

I believe it is only required in certain serial numbers.
There's a one line word of caution in my POH for slips above 20, but no placard. And I have the 13 sump model.
 
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Sorry, been away from POA for a couple days. Thank you for all the good responses. I will check my POH when I get home. If it doesn't have any slip limitations, my instructor will be teaching me. If he learned how to do them, then I am learning.
 
MDeitch1976 said:
Sorry, been away from POA for a couple days. Thank you for all the good responses. I will check my POH when I get home. If it doesn't have any slip limitations, my instructor will be teaching me. If he learned how to do them, then I am learning.
Click to expand...
...and if he didn't, find another instructor.
 
Dan Thomas said:
I'd like to know what changed at serial number 71035 to make the placard unnecessary. I can't see any control surface movement changes.

The TCDS for anyone who wants to figure it out:
http://www.airweb.faa.gov/Regulator...feec0eb8625796d0069d3a9/$FILE/3A12 Rev 82.pdf


Dan
Click to expand...

There is a good chance that what changed was the amount of flap available. At some point they went from 40 deg flaps to 30 deg. That would make a difference. I believe my 175 has a warning in the book about slips with flaps extended as well.....I don't recall the limitations for the 182's and 206's I flew but I think they had something about flaps and slips as well. I do know that the warning is valid and that during some types of flight its possible to blank out airflow to the elevator and rudder when the flaps are extended fully (40deg) which can cause a number of disconcerting actions. In my own experience a full slip with full flaps caused an uncontrolled pitch down at a speed near stall. Pulling the wheel back a little more stalled the plane and we did a slow spin entry as long as the controls were held in place. Pitching forward and centering the rudder pedals created a normal stall recovery. Every plane is a little different so some will and some won't when it comes to these oddities. At altitude its normally not a problem but in the pattern it can be bad.

As for DPE's and slips it should be no problem. My checkride included many slips and a landing on one wheel in the crosswind we had on our return. Examiner was happy with the performance.....of course the Taylorcraft F19 has no flaps so slips are about it for glide path control.

Frank
 
On my checkride, the DPE noted that there was no placard, so he required me to do a slip to land with full flaps. <yawn>
 
MDeitch1976 said:
This maybe another one of those post heavy discussions.

Earlier on in my flight training I had to go out with another instructor because mine was out for several days, and I wanted to fly. The newer instructor I went out with had asked if I had learned to do slips, to help with crosswind, and losing altitude. We discussed how to do them, but never did any of them that day. Back out with my normal instructor again.

While out, we ave a little bit of a crosswind. I figure I am with an instructor, and I try to side slip a little so I can see how we can fly straight in without crabbing. My instructor tells me that the DPE will be all over me for that because I am now cross controlled. More recently speaking with my instructor he says we can work on some slips. Confusion now?

Can I use slips in the check ride for crosswind correction on final? Can I use them if I need to lose some altitude on final in the check ride? Why do some people say not with flaps in use?

Matt
Click to expand...
Here is a question for you....are you sure you were actually slipping and not skidding? There is a big difference. It is not uncommon for a student pilot when first learning slips to get them confused and if the initial instructor doesn't catch it, it can lead to problems later on.

During my PPL training, I flew with a CFI who was a literal bump on a log and never noticed that during my simulated engine failure landings I was skidding base to final and not slipping. That problem was later corrected....
 
Fearless Tower said:
Here is a question for you....are you sure you were actually slipping and not skidding? There is a big difference. It is not uncommon for a student pilot when first learning slips to get them confused and if the initial instructor doesn't catch it, it can lead to problems later on.

During my PPL training, I flew with a CFI who was a literal bump on a log and never noticed that during my simulated engine failure landings I was skidding base to final and not slipping. That problem was later corrected....
Click to expand...

Good point!

Matt gimme a buzz and I'll show you all the slips you want :rofl:
 
Fearless Tower said:
Here is a question for you....are you sure you were actually slipping and not skidding? There is a big difference. It is not uncommon for a student pilot when first learning slips to get them confused and if the initial instructor doesn't catch it, it can lead to problems later on.

During my PPL training, I flew with a CFI who was a literal bump on a log and never noticed that during my simulated engine failure landings I was skidding base to final and not slipping. That problem was later corrected....
Click to expand...

Wind coming from the east, on RWY 32. Right wing low, a little left rudder. And we were flying straight up the center line. Is that incorrect?
 
At what point does a skid occur? Why is a skidding stall worse than a slipping stall?
 
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