Quality of ride is directly proportional to _____?

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Brad W

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...or indirectly proportional to _____?

this is just one of those random thoughts while showering kind of things for you aerodynamicists out there...
I'm thinking in terms of turbulence, mainly but not solely

of course there's things like if there's a lavatory onboard, the quality of foam in the seat, etc...
But in terms of aircraft specs and design....

Remembering a flight I took in a 152 once, after a long time of flying larger and heavier planes. It was a bit of a windy day and I remember thinking this is one reason why I don't like a 152! It was beating me around pretty good

It can't be solely gross weight... the heavier the better, so I have in mind wing loading as being a good relative indicator.

so, a C172 with a wing loading of 13.2#/SF
is a smoother ride than a C152 with a wing loading of 10.5#/SF
and a C182 is even a better ride with a loading of 17.8#/SF

An Aerolite 103 (just as a point of reference) has a wing loading of around 4.5 to 5#/sf...so that must be a truly bumpy ride

So I'm wondering, what other variables would play into comparing different aircraft in terms of ride?
Is it safe to assume that anything with a wing loading of close to 10 or 11 will ride about like a 152?
 
Brad W said:
...or indirectly proportional to _____?

this is just one of those random thoughts while showering kind of things for you aerodynamicists out there...
I'm thinking in terms of turbulence, mainly but not solely

of course there's things like if there's a lavatory onboard, the quality of foam in the seat, etc...
But in terms of aircraft specs and design....

Remembering a flight I took in a 152 once, after a long time of flying larger and heavier planes. It was a bit of a windy day and I remember thinking this is one reason why I don't like a 152! It was beating me around pretty good

It can't be solely gross weight... the heavier the better, so I have in mind wing loading as being a good relative indicator.

so, a C172 with a wing loading of 13.2#/SF
is a smoother ride than a C152 with a wing loading of 10.5#/SF
and a C182 is even a better ride with a loading of 17.8#/SF

An Aerolite 103 (just as a point of reference) has a wing loading of around 4.5 to 5#/sf...so that must be a truly bumpy ride

So I'm wondering, what other variables would play into comparing different aircraft in terms of ride?
Is it safe to assume that anything with a wing loading of close to 10 or 11 will ride about like a 152?
Click to expand...

So yer doin this thinkin while showerin eh. If you start getting light headed, stop.
 
“Ride quality” in a 150 is probably also influenced by the fact that you’re jammed hard up against the door, feeling direct movement of the airframe, instead of slightly isolated from it by a seat cushion.

Not to mention direct transfer of the other door through the person in the other seat’s shoulder smashed into yours. LOL
 
I would imagine that wing loading is most all of it. Some minor impact on that perception may be seat cushion/angle differences which could soften the turbulence. Kind of like riding a motorcycle with forward controls or mid-controls. The forward controls dictate that all of your weight is concentrated on the buttocks and thus the impact from the road gets transferred right up the spine. With mid-controls, your feet/legs can act as a shock absorber and take some of the severity away from the impact as well as the spine not being subject to as much to the abuse due to rider position. I'd think sportier aircraft where you are seated near the floor, feet out forward, and perhaps reclined a bit could "feel" the effects of turbulence a bit more than those aircraft where you sit more upright with legs placed underneath.
 
Brad W said:
...or indirectly proportional to _____?

this is just one of those random thoughts while showering kind of things for you aerodynamicists out there...
I'm thinking in terms of turbulence, mainly but not solely

of course there's things like if there's a lavatory onboard, the quality of foam in the seat, etc...
But in terms of aircraft specs and design....

Remembering a flight I took in a 152 once, after a long time of flying larger and heavier planes. It was a bit of a windy day and I remember thinking this is one reason why I don't like a 152! It was beating me around pretty good

It can't be solely gross weight... the heavier the better, so I have in mind wing loading as being a good relative indicator.

so, a C172 with a wing loading of 13.2#/SF
is a smoother ride than a C152 with a wing loading of 10.5#/SF
and a C182 is even a better ride with a loading of 17.8#/SF

An Aerolite 103 (just as a point of reference) has a wing loading of around 4.5 to 5#/sf...so that must be a truly bumpy ride

So I'm wondering, what other variables would play into comparing different aircraft in terms of ride?
Is it safe to assume that anything with a wing loading of close to 10 or 11 will ride about like a 152?
Click to expand...

I think it mostly comes down to wing loading. The SR22 has a wing loading of around 23-24 lbs and I've never had a "scary" ride in one.. the C172 on a typical hot windy summer day is always a much worse ride. The PA28 has a 14-ish wing loading, and that used to seem smoother to me as well than the C172

Scaling it way up.. I've been told that the MD11 rides bumps real well, and the A380 very poorly.. looking at the wing loading in the two the MD11 is 170 and the A380 is 140 (check the math on that, both sound wrong). I've never ridden in an A380 but have a few MD-11 flights (thanks Swiss Air and KLM) and there is one flight that sticks out landing in Amsterdam where we were warned of "moderate to heavy turbulence" and it was a mostly smooth ride on the way down, it felt like it was just plowing through the bumps. The connecting 737 MALEV flight however was a proper roller coaster on departure
 
Wing loading is huge. So is the flexibility of the structure from a couple perspectives. How much the wing can flex and suck up the bumps is one. The other is how it twists when it bends - if it twists the wrong way it makes things worse.
 
denverpilot said:
Farting in a 150 is an immediate emergency declaration and the offender is grounded pending training on proper use of chemical warfare agents. :)
Click to expand...

Controlled airspace, definition: The amount of gas a person can release in the plane without rendering the copilot and/or passengers unconscious....
 
Was thinking about this again lately...wondering about how an RV-12 ride might compare with something I'm more familiar with. RV-12 Wing loading very similar to the cessna 152
but maybe there's more to the equation...speed, wing flex/design, etc.... Just can't find any fly-off type comparisons or pireps

Found myself going down a rat trail this evening looking at other LSA models looking for comparable to the RV-12. Find it interesting that most manufacturers don't list wing loading for these little birds, or wing area for easy calculations either....
 
Equipment on board to make work load easier.
 
... how much you spent upgrading the panel...
 
Indirectly…. Speed. Always slow down for a smoother ride.

So there we were…

Flying in a air show, goin as fast as we could. Summer, p-cola, getting bounced around so hard your entire scan pattern, a wingtip, was blurry!

Didn’t find out until later the Blues are mostly at 300kts. We were tryin to look cool at over 400! Rookies….
 
Does anyone ever retain what they learning studying for the written?

Ride is turbulence is directly related to wing loading.
 
kgruber said:
wing loading
Click to expand...

wing loading and the lift curve slope.

It’s possible to decrease the impact of turbulence by decreasing the lift curve slope. Wing aspect ratio and fixed slots are two features that can influence the lift curve slope.

L=.5*rho*V^2*Cl_alpha*alpha
F=ma

where:
cl_alpha is the lift curve slope
Alpha is the angle of attack.
 
Grumman Tiger wing loading, 17.2. Plus, 100% oxygen by cracking open the canopy for those days of flying after TexMex! :D
 
I want to say "the amount you tipped her last time", but that's way too inappropriate.

As to the rest, I've had bumpy rides in airliners, and really smooth rides in cubs. I think there are too many variables to get use any math here.
 
I'll add maintenance quality and manufacturer reputation to the secondary factors list that seems to be brewing here.

I have a far more pleasant ride in a plane that I know to have been well maintained and that the wings are not going to clap after bouncing through some sharp bumps. And while I am similarly uncomfortable in a Mooney or a Warrior, I have a different ... experience ... in each one. :D
 
wing loading, sure - as one part

The relationship to the center of lift and center of gravity vs where you are standing likely also have a bearing. I used to travel a fair bit for work and never had a bumpy ride in a MD-80 / DC-9 series planes.. this would be after landing in summer weather in Texas off a very bumpy approach in an Airbus or Boeing, hop in the MD-80, and the bumps just feel different. Especially sitting up near the front you'd hardly feel turbulence.. even though something like an MD-80 and 737 have generally comparable wing loading. The 727 also seemed to ride them well

Back to GA, the Aztec is a comparatively lighter wing loading relative to its size, but it seems to just float through the bumps without much complaint. Having the mass out on the wings oughta help too
 
that's the sort of thing I was pondering way back when I originally asked this question....those other things such as Geometry

Yeah, the old Apache 150 I did some training in, was if I recall correctly a very comfortable ride. Google search to a plane and pilot article shows a wing loading of 12.7 lbs per sf. I don't know if it's true or not...but yeah, very light.... lighter wing loading than say a cessna 172 but a much heavier bird

as Wing span increases you probably feel more bumps in the way of roll
mass out on the wing should dampen the roll
probably the airfoil has something to do with it...but I don't know what...slicing through like a deep V boat vs a flat bottom skiff.
center of lift further away form CG probably induces more pitch from a bump
heavier probably slows a reaction to the bump...but affected by center of lift vs cg where it might amplify it....
Capt Thorpe pointed out structural flexibility
speed gets you into and out of each bump faster, so that might make a given bump more sharp.
yeah sure, the seat design, the foam would have a little something to do with it....

All of these things are a hard thing to estimate though, when comparing two models based on spec sheets and brochures....
I wonder if in addition to things like wing loading, there might be other things to consider that might give clues.... maybe a ratio between cruise speed to maneuvering speed...etc...
 
I assume it also depends on whether you dislike bumps more than going up and down.
 
I wonder how comparable the boating analogy is.. two similar length and similar displacement sailboats can have a dramatically different feel when riding out sea states and various weather. Full keel boats vs fin, wide beam vs narrow, bow design, all have a hand. Not 1:1 relationship but if wing loading is an analog to displacement and wetted hull area I can see a relationship. As with boats (and wings) the holistic picture is important

The Comanche has a relatively light loading, but I prefer the bumps in that plane vs how they feel in a 172.. which seems wobbly and unsure of itself. The Comanche sort of "cuts through it"
 
Quality of ride is directly proportional to… amount of pee in your bladder (less = better).
 
FancyG said:
A Just Superstol rides so much better than a C-172 in turbulence its not even comparable. No need to climb above anything, just whiz along at 2500' or lower.

Worst case throttle back and slow down a a few mph. Flew to ECP for the weekend, could tell the ride in a 172 would have been completely unacceptable.
Click to expand...

interesting data point
If I believe the numbers I see when I google "Just Superstol wing loading", it works out to be 10.0#/SF at max gross. By that measure the ride should be about on par with a cessna 152....certainly not better than a 172!
My gut read would be that a STOL aircraft design would tend to be much more "lofty" and bounce around a lot more....

This is an interesting thing for someone daydreaming about their "next plane" to sort out. Seems to be no way to really sort out which models would make a decent ride platform for your mission...whatever that mission is.
 
Brad W said:
interesting data point
If I believe the numbers I see when I google "Just Superstol wing loading", it works out to be 10.0#/SF at max gross. By that measure the ride should be about on par with a cessna 152....certainly not better than a 172!
My gut read would be that a STOL aircraft design would tend to be much more "lofty" and bounce around a lot more....

This is an interesting thing for someone daydreaming about their "next plane" to sort out. Seems to be no way to really sort out which models would make a decent ride platform for your mission...whatever that mission is.
Click to expand...

the Just Superstol has a relatively low aspect ratio (6.8) and has leading edge slots. Both should decrease the lift curve slope and make it less prone to turbulence than other aircraft with a similar wing loading.
 
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