C172 slips with flaps...POH's updated?

[wilkersk]

I do it all the time. It's not like the plane is going to break up into little flaming pieces.......

I've done it (FWD slip w/40 deg. flaps) several times no problem. I've never done it with a tailwind. But, I'd bet it might be a little uncomfortable if the winds were just right.

 

[Stewartb]

Why do you find yourself in the position to "do it all the time"? Do you plan for it? It seems like a remedy for a F-up. I advocate and use steep final approaches most of the time and I've never needed to slip. I'm scratching my head at the comments that support it, let alone "do it all the time".

 

[Pilawt]

As long as you are aware of the aerodynamics, and maintain control past the area where the rudder stalls it's a NOP.

The pitch-down phenomenon that started the whole thing is not a rudder stall; it's upwash from the pro-slip aileron messing with the direction of the airflow hitting the horizontal tail, basically throwing it out of trim. If you're referring to the slight burble or oscillation you feel in a steep slip with flaps down, that's just turbulent vortex from the outboard end of the flap hitting the horizontal tail.

See Post 23 above for the explanation by a Cessna engineer.

 

[Pilawt]

Why do you find yourself in the position to "do it all the time"? Do you plan for it? It seems like a remedy for a F-up. I advocate and use steep final approaches most of the time and I've never needed to slip. I'm scratching my head at the comments that support it, let alone "do it all the time".

Come visit my airport, with its 1000' AGL pattern (don't descend on downwind, please; old Mrs. Fussbudget who lives down there has the airport manager's number on speed-dial), adjacent Class C surface area that mandates a short downwind and base, and perpetual thermal updrafts from the shopping center parking lot on final. And do it in a lightly-loaded C-172.

Yes, I do sometimes slip with full flap.

 

[Shepherd]

Why do you find yourself in the position to "do it all the time"? Do you plan for it? It seems like a remedy for a F-up. I advocate and use steep final approaches most of the time and I've never needed to slip. I'm scratching my head at the comments that support it, let alone "do it all the time".

I practice it, and other "out of the envelope" maneuvers every time I fly. I want to be able do them, successfully, if I ever need them in an emergency. The only way that happens is with practice. At different airports. Under different atmospheric conditions.
It's worked for me since 1964, I don't imagine I'll change my evil ways at this stage of the game.

 

[Approach_controller]

Not a 172, but I'd slip a 150 with flaps 40 without hesitation when landing in a bowl, which is apparently another no no according to aviator legend. Slight tail buffet at worst. Maybe a prolonged slip would be a bad idea, but on the 150 at least with 40 degrees in I'll see the washing machine someone mentioned and raise them an elevator (the kind in buildings). Doesn't take but mere seconds to lose the extra altitude.

 

[Pilawt]

Not a 172, but I'd slip a 150 with flaps 40 without hesitation

According to Cessna engineer and test pilot Thompson, the caution note on slips with flaps only applied to the 170, 172 (including 175) and 180.

 

[asicer]

According to Cessna engineer and test pilot Thompson, the caution note on slips with flaps only applied to the 170, 172 (including 175) and 180.

But not the 182? Aside from the 180 not having a rolling booger hanging from the nose, what's the difference between it and an early 182?

 

[Pilawt]

But not the 182? Aside from the 180 not having a rolling booger hanging from the nose, what's the difference between it and an early 182?

Good question. Thompson only mentioned 170, 172 and 180. The 180K manual (1977) does have the "should be avoided" language, but 182 manuals for the same era do not. Obviously by then the 182 had morphed into quite a different airplane. I don't have a manual to compare for the early 182s, which as you said are just nosewheel 180s.

 

[ollopa]

We seem to always hear from "survivors" of this maneuver that it's no big deal, from chicken-*****s who've never tried it that it will kill you, and from people who fly some other make/model where slipping with full flaps will probably kill you. I'm not aware of actual accidents attributed to slipping a C172 with full flaps, nor have I heard from people who have done this and experienced a near-death experience. Personally I've never even felt the oscillation while slipping 172M's with full 40* flaps or a 172P with full 30* flaps. In a C172, you just need to keep your airspeed up when you're in a slip and it will be just fine--take it from all the people who've done it and lived to tell the tale.

What's next? Stalling while in a coordinated turn is deadly? Leaning a single-engine is too dangerous because the engine could quit and fail to restart? Maybe emergency descents that split all four cylinders from the shock cooling, overload the wings because of the radical bank, and could make you pass out from excessive G forces. If you're buying all of the above then I have some $10,000 low-capacitance TOSLINK cables that will really improve the tone of your digital audio...

 

[Jimmy cooper]

1000' surrounded by trees IS a long strip! No slips needed. Not in a Cessna, anyway.

I've yet to fly a Cessna that I can't get into places shorter than I can get back out if.

It's obvious he's never flown a 180 or other cessna with big flaps. He's just excercising his misguided mouth.

 

[UngaWunga]

I haven't had the need for slips in the 172 yet. 40 deg of flaps, pull the nose up a bit to lose some speed, and it drops like a rock. If that doesn't work, I go around because I f'd up that approach.

 

[txflyer]

I routinely do not pull 40* until the pavement is just about disappearing under the cowl. Any earlier and I have to drag it in with power.

Practice makes perfect. I'm not happy with my last landing because it's been so hot I have not been practicing.

I floated to long for my taste. But it was hotter than hell, the wind was 90* cross but not bad, and I had the 'get the hell down and in the air conditioning syndrome.'

 

[woodchucker]

For standard pattern approaches, no, you shouldn't need slips. But I've used them a few times in Bravo (SLC and Las Vegas) when given optional landing alternatives that get you on the ground quicker. In Vegas slipped her in from 2000 agl. Granted, you can refuse those options and go with whatever else tower gives you, but I find slips kind of fun anyways.

 

[Pilawt]

The larger point, I think, is simply to be aware of the possibility of the pitch-down phenomenon in pre-'72 models, and be ready to correct in the unlikely event that it occurs. Otherwise, get familiar with operating the airplane in all configurations permitted in the Limitations and make it do what you want it to do.

Know thy airplane.

It's the "aw, pshaw, the manual is wrong" or "the engineers don't know what they're talking about" reaction of some that I don't understand.

 

[mkosmo]

I routinely do not pull 40* until the pavement is just about disappearing under the cowl. Any earlier and I have to drag it in with power.

I've started doing this myself recently, too, and apparently caused a bit of concern for my pilot rated passenger in the right seat.

Sent from my Nexus 9 using Tapatalk

 

[Witmo]

It's obvious he's never flown a 180 or other cessna with big flaps. He's just excercising his misguided mouth.

I admit I've never flown a 180 but the OP asked about a 172 which I have flown. You, on the other hand, prefer to brag about your experience in other aircraft. Others may be impressed but few that have read your postings on other topics would be in that group. I regularly fly a small STOL modified Cessna with large flaps and an engine with 80% more HP than stock that will outperform any 180 ever built. So what? The question was about a skyhawk.

 

[patrick wentworth]

My 1968 172 manual says:
"slips should be avoided with flap settings greater than 30 degrees due to a downward pitch encountered under certain combinations of airspeed, side slip angle, and center of gravity loadings"
--- not quite prohibited---

I have slipped with 40 degrees and survived