Side Slipping Cessnas

[Brown Cow]

What is the general consensus? I can't see anywhere in the C206 poh says it can't be done. However a couple of people have suggested that its not a good idea, and that in C172 poh it says not to do them.

[tinpis]

Gawd ...dont start.....:rolleyes:

http://www.pprune.org/forums/showthread.php?t=187189&highlight=side+slipping

[Brown Cow]

oops, guess i should have searched for it

[poteroo]

Refer to the Day VFR Syllabus - 7.4 p45, and 20.4 p75

Learning to 'slip' is part of your PPL and CPL training. There are several applications after learning the technique. You might not have flaps available or,even with flaps extended, you might not be able to descend steeply enough over trees, amongst other uses such as in crosswing landings.

Search for the difference between sideslipping - for lateral displacement, and forward slipping - for increased rate-of-descent. The terms are contentious!

happy days,

[YesTAM]

C172N POH says don't sideslip with more than 20 degrees flap to avoid oscillation in pitch due to elevator/flap interaction. Thats gospel from the book.

Never seemed to be an issue from 40 degrees flap, speed about 60 KIAS, over the threshold.

[djpil]

Rich Stowell's (http://www.richstowell.com/) new book on Stall / Spin Awareness has the full background to this subject wrt the 172 with some info direct from former Cessna's Manager of Flight Test & Aerodynamics. Some inconsistent characteristics and different characteristics between various models.
In some models, cause of pitch-down in some conditions / configurations due to change in wing downwash at the horizontal tail. Note that fix was introduced at one time but caution note retained in the manual!
Some other models experience pitch oscillations due to flap tip vortex impinging on the tail.

[Fork-tail Dr Killer]

Now if you are as old as I am, you might remember a time when Cessnas had no placards about sideslips and, provided we have received appropriate training we sideslipped the buggers with gay abandon.

Unfortunately some d*ckheads pranged the blooding things and next thing you know they came out with placards warning about the hazards of sideslipping.

I am surprised that Cessnas don't come with a placarded warning

"Pranging this aircraft is NOT recommended"!

I have been sideslipping Cessna 150/152/172/177/180/182/185/206/210/310/402 for 35 years, including those that allow for 40 degrees flaps, and I am still here to talk about it.

If you are seeing an increasing airspeed in a sideslip in which the intention is to loose height on an approach - then you are not using the correct technique. Kick the frigging nose to one side and get the bloody wing DOWN.

Why sideslip an aircraft with flaps?

1) Because you have f*cked up the approach and are too high and really can't be bothered going round.

2) Cause the engine has stopped and you really, really, really need to get into that paddock.

If you can't do a proper sideslip, with confidence, go find yourself an experienced instructor and learn how to do it.

NO, not one of those baby bum fluff grade 1's with a couple of thousand hours in a C152 in the Archerfield circuit, but someone who can actually fly the aeroplane. OK, I accept that there arn't too many of those around these days - but there are a few. Seek them out and LEARN.

Been a while since I have seen as much crap written as is in this and its related site.

Can't say I have ever sideslipped the BE35! What's that mean? I have finally learned how to fly a circuit?

Dr :cool:

PS: I can recommend Wirra Wirra Churchblock. Great red!

[multime]

Presently i fly a cessna.
I,m proud of it.
But if you can,t get it right why side slip @ stall the bloody thing???.
In our industry we drag it in.(400 Mtr airstrips).
But why would you do it?.
More induced drag.Increased stall speed,and just ugly flying.
Cheers
M:ok:

[bushy]

I cannot understand why anyone would want to sideslip a Cessna that has lots of flap. With full flap you have a fairly steep approach angle, and if you are still too high you will find you can actually dive steeply at the threshold without exceeding limiting speeds.(as long as you have all the drag before you start)

[gassed budgie]

If your on a one mile final at circut height in a 172 (a rather silly place to be I might add) and push the nose over with full flap and nail the top of the white arc, you'll struggle to make the runway. If you think you need to side slip a 172 to make the runway, you've blown it. Think again.

[kiwiblue]

I thought this was a wind-up for a while...

why the hell would anyone need to side-slip a Cessna??? If you think you might need to, then you are in the midst of a major SNAFU and you'd best start looking for whatever else may have slipped your attention.

100/200 series Cessnas are extremely good at coming steeply downhill in a controlled manner -there should never be a need to side-slip. The suggestion that you would do so in a 300/400 series Cessna... simply incomprehensible. Why TF would you allow yourself to get so far behind the aircraft??? Why TF do you think a side-slip would be a 'good' way to recover the situation??? Heads out of clackers boys and girls. This is NOT good information going out here.

[sailing]

There are a few scenarios where being able to confidently sideslip (even a flapped aircraft) might be handy. The obvious one is a forced landing into a very short strip.

You want to drag your wheels a foot over the fence to avoid hitting the upwind fence on rollout, but if you're good enough to set that up, and then you get a bit of downdraft/headwind/the approach is a bit more uphill than you thought/etc.. then you are going to hit the fence at 50 kt.:eek:
Better idea is to aim about 1/3 into the paddock and accept less damage by hitting the upwind fence at 20 kt.
Best idea is to set up a moderate sideslip and aim to miss the fence by a foot. If you end up a bit low, just straighten up. If a bit high, increase the slip. Now its easy to arrive a foot above the fence, with the stall warning just starting to bleat, kick it straight and flare.

If you're flying in to a short strip and 'drag it in' using power, you can nail it every time, until the day it quits on final. If you approach as above with the throttle closed you will still nail the approach and if the engine quits all you have to do is turn down the headset volume!:E

But the best reason to sideslip is to get a view of the airfield past the idling Gipsy Major as you bring the Tiger Moth in after some aeros in the sunset!!:ok:

[Wanderin_dave]

Sailing, on that last line i can only say one thing.

Amen, brother, amen!!!:ok:

[HarleyD]

Side slipping (forward slipping) is best learned from someone who actually knows what they are doing and should not be attempted (in contravention of the recommendations in the FAM/POH) because some one on a prune forum sets them selves up as a professed expert and suggests that the OEM doesn't know what they should put in their own manuals.

I have flown soem number of cessna singles (&twins) at least half a dozen more than TFTDK lists and have never really neede to side slip then very much at all for normal lapproach/landing procedures.

The one that needs to be slipped the most is the 188 where a forward slip can be used to reduce the effective span to enable the aircraft to fit through a confined space, or to pull a wing in to avoid a power pole or tree, and you do have to be careful of pitching couples associated with this manoeuvre, especially if you are under a wire at an agle. Another aircraft I have extensive experience in had a much more significant pitch divergency, which would result in a negative G departure if pushed to limits in one direction and an aggressive pitch up in the other direction. Forward slipping can also be used to fly with one wing significantly lower than the other , eg, flying with one wing under the overhanging branches of a row of trees with an aggressive skidding turn to get back out fron under them. This is usually in an aircraft with a very slim (old) POH.

These are not Normal Manoeuvres for Normal pilots, they are for special use and I for one would suggest that low time pilots DON'T do them just coz others can.

If Ag pilots could just lower a bit of flap to do this stuff I'm sure they would. Side slipping if you've got flaps is an abnormal manoeuvre for most pilots and situations. Of course in an emergency landing all bets are off, whatever works is just fine.

Learn how to use flaps properly, and how to side slip properly, not just to fix up what must be the most f%cked up approach in recent history. You are going to need to know how to do it if you're going to get some pitts time in.

OEM's make recommendation based on developmental flight test experience(s). The demonstration of compliance required for certification may not include a test point that has been encountered in development. A certain Weight/CofG/Power/Flap/direction/disharmony ratio/magnitude of deflection/trim setting/acceleration rate/etc.. may result in a divergence that could be irrecoverable in the remaining altitude, be careful.

Why would you side slip a 402 in normal circumstances? I bet the pax (if any) were not too pleased about it.

If you believe that the AFM/POH limitations are merely for the obedience of fools and the guidance of wise ( or self confident) men, please make sure that you know which groud you are in, or become a test pilot.

HD

[HarleyD]

Bugger, didn't mean to do that twice. Sorry, first attempt at this stuff .

[kiwiblue]

Couldn't agree more Sailing -in an emergency situation, all means fair & foul are open for consideration.

But given that this thread is discussing 100 & 200 series Cessna (with the occasional lurch into the lunatic fringe) in apparently normal ops, my contention would be -for the average driver of these types- that a side-slip should not even enter their consciousness! Even a severely ballsed-up approach can usually be recovered in these machines (esp the 40deg models) simply by pulling power, railing all the flap out and pointing down. Then use the power to modify the rate of descent you have established! If even that is not enough, then a simple S-turn or two will more than suffice -without going into the areas of advanced aerodynamics utilised in a side-slip. If that still leaves you high, then you should have recognised the need for and commenced a missed approach at the start of the sequence. Still not too late to, as long as you are judicious in reducing flap as soon as your power is up -and don't 2nd guess yourself!

Other (flapless) aircraft such as the Tiger Moth obviously do require a side-slip on a more regular basis -but those flying them are more likely to have been trained in the proper application of the technique and the consequences of trying too hard alluded to here above.

[HarleyD]

Me ole CFI used to say, "if yer on final in a 172 an the flaps are all out an the throttle is fully closed, that's God tellin ya ter go round"

And he was old when I was young (Cessna 172's were a bit of a novelty I admit) but a distict improvemant on the "pie chaser"

Of course that is supposing that it's not a forced landing

HD

[CHAIRMAN]

Been there!! On my PPL test DCA (in them 1960's days) examiner pulled the power over the field in the ole C150. Ended up way tooo high, full flap (40 degrees those days), no power- thought I'm gonna fail this if I don't do something fast. Pointed the nose straight at the ground and sideslipped, almost no buildup of speed, beautiful roundout, landed on the spot.
Guy was so impressed gave me my licence!! Said don't do it again, but it was safe. Don't think you'd get away with that these days.

[Fork-tail Dr Killer]

Even sober I gotta say "Some of you guys need to explore the envelope a little more"!

Dr:cool:

[HarleyD]

FTDC

Totally agree that envelope for all endorsed types should be explored, but properly, with experienced check pilot or instructor. This in fact should be part of every pilot's training fromm ab initio to advanced. Flight Safety conducts such programs for many types and these courses really do explore the limits of the envelope, but in a very controlled manner with specific learning objectives. Not suggesting a FS course for side slipping a 172 but at least learn all you can do with an instructor, (a proper instructor) before considering disregard of the book. Advanced flight skills courses are available in many places, make use of these people, the life you save may be your own.

Encouraging people to have a gung-ho disregard the AFM/POH limitation and/or guidance, and to do a bit of experimental flight testing is not entirely responsible IMHO.

Please do get out and explore these limits, and then practice to consolidate experience, that is what improves skills and provides higher knowledge, but the policy of "what doesn't kill you makes you stronger" is fraught will hazard for the newbie.

Some pilots make their living spending quite a bit of time outside the envelope, in order to establish where the safe limits should be, and where an aircraft meets compliance with specific standards and requirements, and where it does not, so that when you see a caution or warning in an AFM/POH you can be assured that there is in fact a good reason for this. Raising the question with an informed/experienced pilot is healthy, exhorting others to ignore such cautions is not. Perhaps this thread would have been more appropriate in Flight Test forum, maybe FTDC is in fact a TP, he seems to be a very experienced pilot with a strong aviation background. I have read many posts of his before and generally agree with him, but not this time.

Proceed with due caution BC, talk to many, pay heed to a few, you can choose who.

HD

[sailing]

Totally agree with Harley D., don't play around at the edges of the envelope without getting proper instruction, but some posters here seem to think that a sideslip is advanced aerobatics.
I found that doing an emt course and aerobatic rating gave me a much better understanding of what is and isn't 'in the envelope', and a healthy respect for what can happen when out of it!:eek:

I've used slips in normal ops doing aerial photography in the 172. We had a regular customer (photographer and pilot) who used a medium format camera with a wide angle lens, and getting the wing out of shot when shooting horizontally meant setting up a significant slip to maintain the track. Often did this with some flap extended, with no adverse handling evident, even using full rudder. This was obviously with a forward C.G., (2 pob, nothing in baggage compartment), and at a decent altitude.:ok:

[slackie]

http://www.aerobatics.co.nz/images/MADSideSlip.JPG