Better Turbulence Handling

NealRomeoGolf

NealRomeoGolf

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Is there anything about twin engine models that would make them better turbulence riders than singles?

Somewhat related question: do most piston twins have yaw dampers like @Radar Contact 's 310 or is that a rarity?

Somewhat more specific question: how well do Twinkies ride the bumps @Kristin ?
 
Twins are generally heavier and (I think) generally have higher wing-loading?
 
I find wing loading to be the primary turbulence factor. That.. and yaw. While the PA28 offers a better ride than a 172/182 (in my opinion) it does tend to yaw somewhat.
 
Ryanb said:
You think? I don’t find them any different in turbulence myself.
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It might just depend on the flights themselves too.. but yeah, they seem just a little more sure footed. The tail does wag a bit though
 
Is there a listing somewhere with all different plane models and wing loading stats?
 
As others have mentioned, wing loading is the key to a smoother ride in turbulence. Slowing the airplane down to let it rock & roll over the bumps instead of slam & bang through them helps also. :eek:
 
Based on a bunch of googling, the 310 has the best piston engine wing loading that I could afford. Over 30 on an R model. Most trainers are mid teens. Many others are around 20, including the twinkie.
 
The Aerostar also has 33-34
 
NealRomeoGolf said:
Based on a bunch of googling, the 310 has the best piston engine wing loading that I could afford. Over 30 on an R model. Most trainers are mid teens. Many others are around 20, including the twinkie.
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Like anything in life there's tradeoffs. A high wing loading has some negatives too.
 
I’m not sure that this will help answer your question much, but for what it’s worth:

My understanding is that aspect ratio and slots would also impact turbulence performance. Both low aspect ratio and slots decrease the lift curve slope of a wing/airfoil, which should improve turbulence handling.

anyone can feel free to correct me if I’m wrong, but my thought experiments on turbulence came down to two equations:
F=m*a
L=1/2*rho*V^2*Sw*Cl_alpha*alpha

where:
Cl_alpha is the lift curve slope
Alpha is the angle of attack

The turbulence we feel is cause by a change in wind direction or speed which cause a change in the lift your wing is producing. The only things we have control of during design to influence this are mass, wing area, and Cl_alpha.

Wing loading clearly impacts performance.

The less obvious design parameters are where Cl_alpha can be changed. One way to impact that is by changing the aspect ratio of a wing. A Hershey bar Cherokee wing is lower aspect ratio than a warrior or C-172 for example and I’d expect better performance in turbulence as a result.

———————————

Additionally the Mignet flying flea configuration is also supposed to do better than ‘normal’ aircraft in turbulence.
 
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FastEddieB said:
does anyone else feel this way
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Yes. There could be something to it, the CG/CL, and your ear's equilibrium are all oriented differently with relation to each other. High wings, even 210's, just feel kind of "wobbly" to me

Call me crazy, but I always thought tail mounted engine planes handled better too, IE, DC-9, F-100, CRJs, ERJs, etc. Allegedly the 727 and even the TU-154 :eek: were rock solid in the bumps, although the latter two (at least in my case) are based on internet hearsay.. (so they must be true!)
 
NealRomeoGolf said:
Is there anything about twin engine models that would make them better turbulence riders than singles?

Somewhat related question: do most piston twins have yaw dampers like @Radar Contact 's 310 or is that a rarity?

Somewhat more specific question: how well do Twinkies ride the bumps @Kristin ?
Click to expand...

The Twinkie rides fine. Wing loading is the thing. I haven't make a scientific study of it, but more mass and higher wing loading are the major factors. It is worth watching out for Dutch Roll tendency. That can turn a good ride into a bad one. You won't get me in the back of a V-tail in turbulence. The Barons have some of that too. The 310 a bit as well, but not like the Beech's.
 
FastEddieB said:
I have found that, all things being equal, low wings just feel a little more "solid" in turbulence. Maybe something about sitting on top of a wing with typically more dihedral, rather than suspended under a wing.

Just curious - does anyone else feel this way?
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I find the Hershey Bar wing Cherokees more stable than the high wings.
 
What does turbulence actually do to a wing? It suddenly changes the angle of attack. If I recall correctly (it's been almost 70 years) the higher the aspect ratio the greater the change in Cl (lift) for a given change in AoA. Therefore, other things being equal, a higher aspect ratio wing should generate more occupant bumpiness.
 
Buy a Bellanca. The wood wing soaks up most of the bumps.
 
FastEddieB said:
I have found that, all things being equal, low wings just feel a little more "solid" in turbulence. Maybe something about sitting on top of a wing with typically more dihedral, rather than suspended under a wing.

Just curious - does anyone else feel this way?
Click to expand...

It is somewhat dependent on the airplane, but I’ve always felt the high wings offered a better ride. I attribute it to the “pendulum effect” they have, which is also presumably why they don’t need as much dihedral to be stable.

As far as the original question goes, I think wing loading and the mass of the plane are the big factors. But interestingly enough, I think the cub handles turbulence the best of anything I’ve flown. The airplane is light and so is the wing loading which seems to allow it to just ride the turbulence like a boat would ride waves on an ocean.
 
mondtster said:
pendulum effect
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Actually that's a good point. Might be why they feel "wobbly" to me.. with the CG under the CL that could explain why they feel less "sure footed" to me

Does mass really matte? Sure heavier objects need more force to move, and as such may be more "immune" to rough air.. but isn't wing loading the correct analog to account for that? 24 lbs wing loading is 24 lbs wing loading whether it's a 500,000 lb plane with massive wings or a 2,400 lb plane with normal sized wings.. or am I completely missing something?

How much does wing flex play into this? Some gliders have tremendous flex. I've always wondered if the slight flex that the Cirrus offers helps to dampen some of the bumps
 
FastEddieB said:
I have found that, all things being equal, low wings just feel a little more "solid" in turbulence. Maybe something about sitting on top of a wing with typically more dihedral, rather than suspended under a wing.

Just curious - does anyone else feel this way?
Click to expand...

I do and I thought to mention it but I might be biased ...
 
I found my RV6 was much more easy to fly in turbulence(than my v35 or c172)since the stick was much more sensitive and easier to make adjustments(attitude/roll) while it took more tugging, pushing, rolling with the 172.
 
FastEddieB said:
I have found that, all things being equal, low wings just feel a little more "solid" in turbulence. Maybe something about sitting on top of a wing with typically more dihedral, rather than suspended under a wing.

Just curious - does anyone else feel this way?
Click to expand...
A stiffer wing would feel different than one that flexes more. With a strut in the middle, you likely get less flex.
 
NealRomeoGolf said:
Is there anything about twin engine models that would make them better turbulence riders than singles?

Somewhat related question: do most piston twins have yaw dampers like @Radar Contact 's 310 or is that a rarity?

Somewhat more specific question: how well do Twinkies ride the bumps @Kristin ?
Click to expand...
Sounds like you got some good opinions. Wing loading is mainly what I’ve heard. I’m not as up to speed on the physics/dynamics of it all. I will say, in the past 20 years I’ve flown/flown in many different types of planes and the 310 does seem to handle the bumps better than most. Seems strange with a lot of weight so far out in the tips but I guess they provide their own lift anyway.

Last (first) time you flew with me I had just bought her and was still getting the feel. If you’re ever around and want to go up, let me know. I’m still learning but after several years and a few hundred hours I’m much more at one with her.

I’m not sure the percentage with Yaw Dampers and while it’s far from a necessary item, I sure do love it!
 
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