using S turns....to reduce altitude?

classicrock

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acousticguitar
S turns are a maneuver( I have practiced with my CFI) that I thought were to better adjust to or build skill with turning into or away from wind.

until this last week

coming in on final approach, the VASI lights indicated we were too high. my instructor told me to initiate a narrow S Turn immediately(while descending). so I did. (there were very little wind conditions)

it WORKED beautifully.got us right on glide slope.

it would have never occurred to me to do that.

any other pilots done an S turn...on final?
 
I would of just slipped, or maybe reduced throttle to force a faster descent, not into changing headings on final.
 
Slipped, yes, never done an S turn on final though. I've seen them done often enough by commercial airliners for separation, which is kind of funny to watch.

Most small airplanes you would have to be unbelievably high on approach to need an S-turn I'd think.
 
Yeah it helps to lose altitude or even increase sep on final with other traffic. A slip works well for altitude loss but in an aircraft like mine they're not recommended. With no flaps, either S turn or buck stall the thing all the way down.
 
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Narrow S turns aren't that effective unless you're uncoordinated. Sharp S turns will work quite well, but a slip is both easier and safer.

Honestly, in a 172 or especially 182, you can get a fairly strong descent by pulling power to idle, dropping the flaps all the way, and pitching for 60 KIAS. When back on glide, add power back in at constant airspeed, and you're configured for a real nice approach without scaring passengers (they don't like slips or S turns much).
 
I would of just slipped, or maybe reduced throttle to force a faster descent, not into changing headings on final.

I agree. I'm not sure I would introduce the concept of maneuvering on final to a pre-solo student as a way to salvage an approach.
 
Also keep in mind, a slip or an s turn should never be used to band aid a bad approach. Just go around and try it again. That would be the safest thing to do IMO
 
Narrow S turns aren't that effective unless you're uncoordinated. Sharp S turns will work quite well, but a slip is both easier and safer.

Honestly, in a 172 or especially 182, you can get a fairly strong descent by pulling power to idle, dropping the flaps all the way, and pitching for 60 KIAS. When back on glide, add power back in at constant airspeed, and you're configured for a real nice approach without scaring passengers (they don't like slips or S turns much).
If you can't judge your correct altitude in something like a 172 or 182 on final you may need additional training. They both drop quickly when full flaps are employed and the throttle pulled back. Pretty docile airplanes.
 
coming in on final approach, the VASI lights indicated we were too high. my instructor told me to initiate a narrow S Turn immediately(while descending). so I did.
Zero power and full flaps on many aircraft will bring you down much steeper than the VASI - even in my no-flaps taildragger I am all white on the VASI until I am about to touch down for a power off approach. So, unless you are way beyond high, all you need to do is pull the black knob and wait. You will get down there.

Then there are slips. The key to slips is to understand which way to slip. If you have some guy in the other seat, you slip to the right. If you have a babe, you slip to the left (Assuming you are a guy). That may seem obvious, but some guys just don't get it.

And, no. I ain't never done no S turns on final. But I have done slips more times than I can count. (And, if the rudder ain't all the way to the floor, it's not a serious slip.)
 
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It wastes time, so this can be useful in a few situations. (Like when the guy ahead of you isn't getting off the runway quick enough. )

Obviously the longer period of time you spend at a particular rate of descent, the more the loss of altitude.
 
Can't say that I've done them to lose altitude, but I definitely use them when needed to increase separation if I am gaining on landing traffic that is ahead of me.

Not so much to lose altitude, but to fly a longer route so that you can lose more altitude over a shorter ground distance.
 
S-turns kind of go against the "stable approach" mantra...I'd probably use a slip instead.
 
It wastes time, so this can be useful in a few situations. (Like when the guy ahead of you isn't getting off the runway quick enough. )

Obviously the longer period of time you spend at a particular rate of descent, the more the loss of altitude.

I just start slow flight if I'm needing some extra separation space... if that doesn't work it's go around time.
 
A little off the subject... Why are you using VASI as a student... Getting used to them at this early stage of training IMHO is not a good thing... It is better to learn correct site picture without a crutch so when you start solo XC to airports without VASI you can land the plane safely...
 
A little off the subject... Why are you using VASI as a student... Getting used to them at this early stage of training IMHO is not a good thing... It is better to learn correct site picture without a crutch so when you start solo XC to airports without VASI you can land the plane safely...

How do you unsee a VASI at an airport that has one?
 
The lessons I had were: S-turns on final for separation, slips on final for altitude.
 
Not my favrote way to loose altitude, I'd rather widen my pattern or slip, I don't like turning away from a runway I'm landing at.
 
How do you unsee a VASI at an airport that has one?

Easy! In over 4000 hours of flying, mainly at short strips of around 2000 feet I've never paid any attention to a vasi. I'm simply watching for traffic , always, and trying to land with as little time as possible in the pattern as that's where someone can kill me. It's worked so far. A long final in a light aircraft is asking for trouble.
 
I don't think it's bad to utilize the vasi/papi at all when you're starting out, it helps you to verify that your sight picture is correct.

And kudos to the guy that can ignore it, but that's a pretty hard thing to do on a mile final.
 
I don't think it's bad to utilize the vasi/papi at all when you're starting out, it helps you to verify that your sight picture is correct.

And kudos to the guy that can ignore it, but that's a pretty hard thing to do on a mile final.
Exactly. Nothing wrong with using a VASI/PAPI as a student pilot to help get the sight picture down as long as your CFI is mixing it up and having you land at runways without vertical guidance as well.
 
Which do the pax appreciate less?
I've never had a new passenger in love with a slip, the s-turns are reportedly unnerving too.
Throw everything out including speedbrakes if you gottem, before slip/turns. Plan better!
 
How do you unsee a VASI at an airport that has one?

Approach with all the lights white.

It's not very hard, even fully stabilized. You just need a somewhat steeper approach.

Or just ignore it. Most of them are much further along the runway than we want anyway. It's much the same as approaching 25L at Livermore. You can't use the PAPI because it's for 25R.
 
Especially at night and at a unknown airport I'll fly the PAPI or VASIs, I'm in no rush to land on short final, if I'm super familiar I might speed things up a little.
 
I was taught pretty early how on to use (pretty steep) S-turns to lose altitude quickly in an emergency decent. I now find using slips and full flaps (yeah, that may start a comment or two, some planes don't like that combo) to be just as effective and a bit more comfortable for me.

Good to have lots of tools in the box though.
 
How do you unsee a VASI at an airport that has one?

Really? that's what you got out of my post?
Seeing it and basing your approach corrections based on it are two different things... I see the vasi... I don't usually base my approach on it...
 
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Really? that's what you got out of my post?
Yes, really. There is no reason to categorically ignore the VASI/PAPI if is there. You CAN use one and not become dependent on it and part of that is the CFI's responsibility.
 
I was taught pretty early how on to use (pretty steep) S-turns to lose altitude quickly in an emergency decent.
Interesting. Not saying you are wrong, but I was always taught the steep spiral for emergency descent vice S-turns.
 
Why is it safer? :confused::dunno:

'Cause an airplane going in a straight line is inherently more predictable than one that is zigzagging.

If you're trying to make drag, that requires large bank angles. Just making the path longer can be done by going way off the centerline, something you don't have to do for a slip.
 
Interesting. Not saying you are wrong, but I was always taught the steep spiral for emergency descent vice S-turns.

I'm talking about on short final. Specifically, my instructor pulled the power on me at about 800' AGL departing runway 32 and had me perform an emergency landing on runway 5 (runways cross at ~mid-length, this was at New Bedford, MA, with the cooperation of the tower).

I still routinely practice power-off 180-degree precision landings; just did a couple yesterday with a CFI. To me, this is the ultimate test of my ability to manage the airplane's energy in an emergency.
 
I'm talking about on short final. Specifically, my instructor pulled the power on me at about 800' AGL departing runway 32 and had me perform an emergency landing on runway 5 (runways cross at ~mid-length, this was at New Bedford, MA, with the cooperation of the tower).

I still routinely practice power-off 180-degree precision landings; just did a couple yesterday with a CFI. To me, this is the ultimate test of my ability to manage the airplane's energy in an emergency.
Yeah, that does make sense.

When were you training at EWB? That is the airport I soloed at in 2005.
 
S-turns for separation definitely. In my Piper I have a nice enough descent rate that usually just pulling the power is enough. In those rare circumstances when I've had to lose altitude quickly, I'll just slip it down like others have said.

This weekend I was coming back from a trip and tower kept me pretty high until I got close to the field (lotta traffic outbound) slip got me down nicely. If I had my wife in the plane, I don't think either an S-turn or a slip would make her happy :)
 
Yes, really. There is no reason to categorically ignore the VASI/PAPI if is there. You CAN use one and not become dependent on it and part of that is the CFI's responsibility.

As a matter of training, I think too many crutches make for a weak foundation... I remember my first instructor taught me to turn to base at a water tower... didn't help much when there was no water tower... Yes the VASI is nice... I'm just suggesting it would be better without relying on them, in the beginning...
 
Some planes have a very effective slip and may be a better choice on final. In my Lancair, a slip is about as effective as my cabin heat - so ineffective it is not used. S turns however are quite effective in the Lancair and as such I use them probably with about the same frequency that others use forward slips.
 
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