In general higher wing loading means better turbulence handling. But that often means the aircraft is naturally fast. Can a plane be slow and also handle turbulence by making the wing smaller and adding all sorts of lift adding features like slats, flaps, wing fence etc.?
Posted by No-Perception-2023@reddit | aviation | View on Reddit | 13 comments
I hope i explained well. For low altitude and low speed sightseeing.
vorko_76@reddit
Where does this statement come from? From a physics point of view, i dont understand the logic behind it.
Charlie3PO@reddit
Higher wing loading essentially means more weight and more inertia, meaning the same gust will have less of an effect on the flight path. More weight also means higher stall speed though. It's a pretty generalised rule, but it does check out and it is correct as a general statement. It's not an exact rule though.
Put simply, which aircraft do you think will get knocked around more A heavy aircraft or a light aircraft? Assuming both are the same size with the same wing area
runway31@reddit
Now to add complication, what about a 172 with the same weight, same wing loading, but flexy wings? Will the flexibility in the wings work like suspension and smooth out the bumps? Can we make higher wing loading, flexier wings to maximize the aerodynamic inertia as well as smoothing. I suppose the 787 and a350 already do some of this, both structurally and with smoothing flight control laws.
Could a relationship be drawn between wing loading and aeroelasticity in terms of turbulence?
No-Perception-2023@reddit (OP)
From logic mostly. For example gyrocopters have similar controls. The wing/blade area is very small but it generates lift by spinning. It has very high wing/blade loading yet it can fly very slow. The design is very different but controls are pretty much the same. My idea is to have a small fixed wing but add lots of lift to it by slats, vortex generators. I just want to know can that work?
vorko_76@reddit
I seriously do not understand the reasoning…. And not sure where you want to arrive at.
Higher wing loading, less turbulences why?
Slower, less turbulences ok… and if you generate lift one way or another you could slow the plane, at the extreme the plane could even be static. But then why?
No-Perception-2023@reddit (OP)
I want a slow flying ultralight that gets less affected by mechanical turbulence. Something that can cruise at 40km/h for low altitude sightseeing.
vorko_76@reddit
What is mechanical turbulence? Ive been studying 3 main types of turbulences in school but never heard about “mechanical”.
I would suggest you to check the different formulas but im not so sure it works as is. The impact of an airflow is also function of the wing surfacr, not only the airspeed.
No-Perception-2023@reddit (OP)
Mechanical turbulence is caused by mountains, buildings etc.
Charlie3PO@reddit
High wing loading is better for turbulence.
"The lowest wing loading has the largest load factor response to turbulence..."
Source: NASA Contractor Report - A procedure for assessing aircraft turbulence penetration performance - Page 33 (44 of the PDF file) (link below)
There is also a graph on page 34 of this link which shows the values of load factor generated by each unit of turbulence for different wing loadings. It clearly shows that higher wing loading generates less aircraft G forces than low wing loading (i.e. a better ride)
Link: https://ntrs.nasa.gov/api/citations/19700013368/downloads/19700013368.pdf
Unfortunately for OP, higher wing loading also generates higher stall speed (i.e. weight weight and/or less wing area to carry that weight), which is the premise of OP's question. I.e. How do you achieve a low stall speed with a high wing loading.
Charlie3PO@reddit
I don't know why OP is getting downvoted here, high wing loading aircraft ARE generally better in turbulence than low wing aircraft.
What do you think handles turbulence better? A C172 at minimum weight with 1 person and almost no fuel? Or a C172 near MTOW (I.e. higher wing loading). The heavier aircraft, having more inertia, will handle the turbulence better. In other words, safe external force due to turb, but more weight, meaning less acceleration and change in flight path. BUT, it's minimum speed is also a little higher, due to higher stall speed.
OP, what you need is a wing which has high maximum lift coefficient, but one which also has a very wide AOA range with a very high critical/stall AOA.
No-Perception-2023@reddit (OP)
So my theory is somewhat true. A small wing with efficient airfoil design coupled with high lift devices (flaps, slats) could give me good turbulence handling and low speed at the same time.
Charlie3PO@reddit
2 possible reasons behind the downvotes. Firstly, it's reddit, people who don't know what you're talking about will simply downvote rather than make an effort to understand. There's a good chance that many people in this sub have zero aviation qualifications. Which leads into the second point. Knowing you're posting in a sub with a relatively low level of aerodynamics knowledge, you should provide a source. 'Logic' is not a source, even if it is correct in this circumstance. So it's kinda on you for not knowing your audience.
"The lowest wing loading has the largest load factor response to turbulence..."
There is a graph on page 34 of this link which shows the values of load factor generated by each unit of turbulence for different wing loadings. It clearly shows that higher wing loading generates less aircraft G forces than low wing loading (i.e. a better ride)
Link: https://ntrs.nasa.gov/api/citations/19700013368/downloads/19700013368.pdf
Also check out Andras Sobester on YouTube. He has videos on aircraft design, including wing sizing. It's pretty generalised and probably won't answer your question, but might be a good starting point to learn the basics.
runway31@reddit
Downvoted cause i dont understand what you’re talking about…