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Magnus effect / Flettner wing etc.

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Pops

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Just take a wood lathe stick (36"x 11/2" X 1/4" thick) and throw it hard out forward with top back spin and it will climb about 30 feet. The kids in my neighborhood couldn't afford model airplane engines.
Would that be sort of like a straight boomerang ? At one time I got sort of good throwing a boomerang. Was teaching my youngest son when he was about 13 years old, trying to teach him to catch it when it came back, when he tried he got hit in the mouth and busted his lips, no more boomerangs for him.
 

BBerson

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Would that be sort of like a straight boomerang ? At one time I got sort of good throwing a boomerang. Was teaching my youngest son when he was about 13 years old, trying to teach him to catch it when it came back, when he tried he got hit in the mouth and busted his lips, no more boomerangs for him.
No. A boomerang is a stable airfoil wing thrown with a flick from a hold on the tip to spin it forward.
A Flettner stick is held at midpoint and flicked with back spin around the long axis.
It makes a strong buzz sound. I don't remember the exact size. Most any slat will work, I think.

I guess you were not as poor as you thought...:gig:
 

Pops

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No. A boomerang is a stable airfoil wing thrown with a flick from a hold on the tip to spin it forward.
A Flettner stick is held at midpoint and flicked with back spin around the long axis.
It makes a strong buzz sound. I don't remember the exact size. Most any slat will work, I think.

I guess you were not as poor as you thought...:gig:
I know about Boomerangs, like I said, I was somewhat good with one, but I never heard of a Flettner stick before. If I had known about them, I would have made them. Made my bows and arrows from scratch and made hunting knifes with my grandfather's forge and anvil. I still have things I made as a kid, but no Flettner stick.
 

Aesquire

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Not much need to go back to sail power for ships. Looks like unconventional oil reserves have pushed back peak oil another 100 years.
The quest for cheap is not dead when the price of fuel goes temporarily down. It's just put on the back burner. The idea was sail assist with automated rotor sails. Nearly free energy is hard to pass up for bean counters. It did take power to spin the rotors, but all in all it was a gain. Just not, apparently, one you could make money on.

As a prime example that cheap is king, look at commercial air liners. Notice how all of them in the U.S. pretty much banned smoking at nearly the same time? It had nothing to do with the noxious habit. It was all about money. Air pressurization and flow though the cabin takes fuel. When people smoked, they had to keep the flow up enough to make the passengers happy. After all, you can SEE smoke just hanging in the air. When they banned smoking they could turn down the air without passenger complaint, and made millions of dollars in fuel savings.

I'm old enough to remember the old days. Bring an blood oxygen sensor with you on your next flying bus trip.
 

Swampyankee

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The quest for cheap is not dead when the price of fuel goes temporarily down. It's just put on the back burner. The idea was sail assist with automated rotor sails. Nearly free energy is hard to pass up for bean counters. It did take power to spin the rotors, but all in all it was a gain. Just not, apparently, one you could make money on.
Wind-powered ships were economically viable up until the First World War, where commercial sail was mostly killed off (quite literally) by German raiders: sailing ships couldn't operate in convoy. Interestingly, coal was cheaper than oil, but a coal-powered ship was more expensive to operate than a ship with oil-fired boilers, as the former needed a larger crew and more maintenance down-time (coal is filthy, and coal's combustion products are corrosive and include abrasive ash) than did a ship using oil fuel. Fuel for diesel ships was more expensive than fuel for steam ships, but, again, diesel displaced steam because the latter cost more: steam plants need 8 to 12 hours to go to full power after being shut down, they need larger crews than diesels, and tend to need more maintenance.

As a prime example that cheap is king, look at commercial air liners. Notice how all of them in the U.S. pretty much banned smoking at nearly the same time? It had nothing to do with the noxious habit. It was all about money. Air pressurization and flow though the cabin takes fuel. When people smoked, they had to keep the flow up enough to make the passengers happy. After all, you can SEE smoke just hanging in the air. When they banned smoking they could turn down the air without passenger complaint, and made millions of dollars in fuel savings.

I'm old enough to remember the old days. Bring an blood oxygen sensor with you on your next flying bus trip.
And cleaning. Companies that banned smoking in their offices reduced their cleaning bills quite a lot.

The airlines still change the air in the cabins, but without the filthy smoke, they don't have to do it as often. They also spend a lot less on cleaning the cabins, and minor maintenance issues like replacing seat cushions and seat backs used to snuff out cigarettes.
 
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jedi

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The quest for cheap is not dead when the price of fuel goes temporarily down. It's just put on the back burner. The idea was sail assist with automated rotor sails. Nearly free energy is hard to pass up for bean counters. It did take power to spin the rotors, but all in all it was a gain. Just not, apparently, one you could make money on.

As a prime example that cheap is king, look at commercial air liners. Notice how all of them in the U.S. pretty much banned smoking at nearly the same time? It had nothing to do with the noxious habit. It was all about money. Air pressurization and flow though the cabin takes fuel. When people smoked, they had to keep the flow up enough to make the passengers happy. After all, you can SEE smoke just hanging in the air. When they banned smoking they could turn down the air without passenger complaint, and made millions of dollars in fuel savings.

I'm old enough to remember the old days. Bring an blood oxygen sensor with you on your next flying bus trip.
I disagree. FAA regulations are the reason all US airlines banned smoking at the same time. Regulations were driven by blue room fire hazard to some degree.
 

jedi

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Just take a wood lathe stick (36"x 11/2" X 1/4" thick) and throw it hard out forward with top back spin and it will climb about 30 feet. The kids in my neighborhood couldn't afford model airplane engines.
You can do the same with a 3x5 card. Stand at the top of a few stairs and launch by giving a downward push on the trailing edge.
 

Bigshu

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I dearly hope for that day as well. There are going to be two routes to get there, and I'm starting to get a clear indication of which one will ultimately win out.

Firstly, we can rationalize our flight training system, and the regulatory system that deals with producing new airplanes. See, airplanes are relatively easy to fly. Except for landing, I'd put it easily on par with the skill level necessary to drive a car. Even landing isn't that difficult. But our flight training system emphasizes numbers and rote learning instead of "flying the airplane", and our regulatory system makes it so hard to bring a new type-certificated airplane to market that few new airplanes ever appear, and we're stuck with 50+ year-old designs being market leaders, a situation that really doesn't happen in any other major industry.

Secondly, we can wait for the arrival of largely automated "quadcopter-like" flying machines, which ultimately won't require a pilot's license because the operator will simply enter a destination and the machine will do the rest. Much the way cars are going right now. The technology is already here, excepting the battery/energy-storage technology that gives them useful and practical range and flight duration. The fact that they'll be VTOL is a huge bonus. We may, actually, get the "flying car" of sci-fi legend out of this technology. But you won't be a "pilot", and it won't be like flying an airplane is today.

Me, I like flying an airplane. When I switched from power to gliders, the scales were lifted from my eyes with regard to flight training. It's entirely possible to train a safe and knowledgeable pilot in a training system that emphasizes "flying the airplane" and de-emphasizes numbers and rote procedure. And you get a better pilot faster and cheaper in such a system. The "numbers and systems" knowledge can absolutely be added later for someone who wants to do "serious" cross-country, or ultimately land in a commercial airline job. You don't need that knowledge to safely fly an airplane in the US airspace system.

However, much of the "way forward" in making airplanes into an "everyday travel machine" is clearly in directions the FAA and other regulatory agencies have no desire to go. The recent "revamp" of FAR 23, along with what happened to the "Pilot's Bill of Rights" in actual legislative and regulatory terms makes that very clear to me. The FAA has little taste for pilots independently "driving" their little airplanes around - it's not amenable to bureaucratic regulation and control. Whereas computer-controlled "personal flyers" that take all the control away from the occupant, and automatically transact their flight plan with the FAA's computers, is much nicer to the bureaucratic eye. Oh, the FAA is going to groan and complain and drag their feet, much as they've done on the "drone" question, but ultimately they'll embrace a system that regulates the skies like clockwork.

So, yes, I think that the "quadcopter-like" personal flyer is going to win out, and our piloted airplanes are going to become a niche, not unlike racing antique cars is now. Just the economics of getting a pilot's licence (versus not needing one) is going to make that happen. Right now it takes about $10,000 to get a PPL-SEL from a commercial flight school. If the price differential between a used airplane and "personal flyer" is anywhere near that amount, the public is going to vote with their wallet and go with the automated machine. We're already seeing the vast interest in driverless cars - anyone who thinks the same forces won't be at work in aviation is, I believe, fooling themselves.

I don't like it, I don't want it, but I'm also not naive enough to think that it won't happen.
There is one area where I think the autonomous personal flyer makes sense, much like in driverless cars, is the ability to maintain the personal autonomy of an aging population. One of the big problems in driving cars in the safety bell curve. Young inexperienced drivers, and older, skills diminished drivers cause the bulk of accidents. One of the worst things to watch is a senior citizen being told they can't renew their driver's license. The loss of the ability to go places without relying on other is a terrible thing. Driverless cars will allow that flexibility to be given back to thousands of aging seniors (as long as they can remember and articulate where they want to go!). In a similar manner, personal flyers that take much of the burden off the occupant will extend the flying days of a lot of pilots (who are already flocking to basic med to avoid being grounded by routine, well controlled medical conditions). There's still joy in getting in the air, even if you aren't at the controls.
 

TFF

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No need to get into the air if not at the controls. Pilots are like horsemen. They do or don’t want to. They don’t want to be lead around a ring by someone while they sit on a horse. When people can’t fly themselves, they quit. They all have buddies they could ride with but never once have I seen one go. It’s about personal mastery not bobbing around in the air.
The car has merit but for me with cars if it becomes required, I’m walking or taking the buss. Not interested in not doing it my self. I don’t need to be anywhere if I can’t drive. Probably shouldn’t be anywhere but home anyway at that point.
 

Bigshu

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No need to get into the air if not at the controls. Pilots are like horsemen. They do or don’t want to. They don’t want to be lead around a ring by someone while they sit on a horse. When people can’t fly themselves, they quit. They all have buddies they could ride with but never once have I seen one go. It’s about personal mastery not bobbing around in the air.
The car has merit but for me with cars if it becomes required, I’m walking or taking the buss. Not interested in not doing it my self. I don’t need to be anywhere if I can’t drive. Probably shouldn’t be anywhere but home anyway at that point.
Sure, if you have your groceries delivered, and your doctor makes house calls, I think that's fine. The pandemic has shown how easy it is to get home delivery of just about anything, and Teladoc is available now.
 

TFF

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I just don’t think in the hobby market of flying, an autonomous flight means anything. It’s a different segment. In marketable moving of people sure. But as expensive as this hobby is it is no different than stamp collecting or playing golf. It is the interaction that that sells. A ride is why families of most airplane owners don’t care about the airplane. Most think they are stuck in the can until dad gets us to the beach. That’s why four seat planes sell but rarely have more than one fly. The rest are not enjoying it because they are not active. Unselfish option to have the open seats, but rarely used. I would see it like a ride at Disney, you get on and say wow, but the next time you just watch the kids.
 

trimtab

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In 80 years of aviation, crashes and failures and deaths in GA still happen for the same reasons. The state of the practice of flying has not moved the needle. The cohort of persons entering the flying arena is a mix of intellectual and mechanical abilities, the equipment has not changed significantly to change the trajectory in meaningful ways, and so the stagnant result cannot even be said to be surprising....the lack of progress in the outcome is carefully planned for even if the desired outcome is somehow different than the actual one.

A safe and accessible entry into GA requires radical change to survive, let alone grow. This means safe flight should be available to persons without extraordinary knowledge, ability, or stamina to use the airspace safely and effectively. The present system depends on heroic myths or is otherwise evaluating the intelligence, judgement, and pretended abilities of sash wearing individuals to be safe or capable.

After over a hundred years of aviation, a platform that doesn't ensure a person of roughly average intelligence, mechanical ability, and judgment to achieve safe flight with a record similar to driving a car is an utter failure on an astounding scale given the costs being thrown in the aviation wishing well that are, by the central dogma, ensuring safety.

The definition of insanity has been described as doing the same thing over and over and expecting a different result. I think GA is the perfect example.

I think removing judgement and detail from flying via autonomous control could be an avenue to progress. People cannot I'm general be expected to do any better on their own. This includes a different regulatory structure. The FAA has neither the intellectual ability, the motivation, the funding, or the mission to facilitate significant changes to GA safety, access, or technology. They failed in the Nexgen arena miserably, FSBO's are almost entirely unavailable for innovation, and there is nothing to suggest it has any plan except to introduce minor deck chair arrangement changes that are usually irrelevant and unaccountable to outcomes in any way. Usually, they are more interested in "doing something" instead of "doing something that works".

Reducing choice and judgment from complex activities has been a huge benefit in a range of other important technologies and has spurred growth and innovation. It's time that aviation get into the act.
 

BJC

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Reducing choice and judgment from complex activities has been a huge benefit in a range of other important technologies and has spurred growth and innovation. It's time that aviation get into the act.
If that is what you want, go for it.

But, don't impose your judgements on me: I choose to enjoy the act of fully piloting my airplanes in all dimensions.


BJC
 

trimtab

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You will have the option. You can also add spinning dishes on sticks and juggling if it makes it more fun. This is sarcasm, but it isn't when adding details amounts to mere gamifcation of flying.

A lot of people can operate present equipment with a high degree of safety and effectiveness. Some of them can spin plates on sticks and file their nails at the same time. That doesn't mean everyone can, and it means those people are more likely to die because they can't seem to keep their CHT's in the green, their airspeeds in an appropriate manner, avoid CFIT, keep enough fuel in their tanks, etc.

Automating engine management solutions, dumping the sanskrit of abbreviated weather briefings that more studies show most VFR pilots ignore, etc., are all contributors to accidents and barriers to flight for many and are superfluous to necessity. Did glass panels improve CFIT or any other measurable metric of safety? Has ADS-B? I haven't seen anything that can say that they have. The underlying problems are still there.

For most of the people I've flown with (I likely have very bad luck in flying acquaintances), I would much rather they had some other platform to fly in than their present GA planes. I don't fly with them.Because the social aspects of flying are often important to them on some level, this is something that has led to some tensions. Yet in 37 years of flying, three of them have died in crashes form running out of fuel, running into weather, and something indeterminate, but probably playing A-10 pilot in a Cessna. Another several of them have crashed, some with permanent injuries. Most of my flying is in the backcountry, very little flying with pavement, and the accident thing is likely something I should expect on some level. But the few times I've flown with others since I was a teen have largely been an exercise in suppressed deep concern. I'd rather they had a simpler, safer way to fly.

For the topic at hand, The Flettner/Magnus approach has the problem with drag being proportional to the square of the rotational velocity, whereas the lift is quite a bit less. L/D ratios rapidly collapse.

Super neat demonstration of Kutta, though.
 
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Sockmonkey

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Automating engine management solutions, dumping the sanskrit of abbreviated weather briefings that more studies show most VFR pilots ignore, etc., are all contributors to accidents and barriers to flight for many and are superfluous to necessity. Did glass panels improve CFIT or any other measurable metric of safety? Has ADS-B? I haven't seen anything that can say that they have. The underlying problems are still there.
It's been shown that rows of dials are pretty much the worst way to impart information to someone occupied with another task. Like flying a plane for example. Pictographic symbols on an LCD are better in that your brain doesn't need to translate anything. An animation of a swirly dark cloud moving towards a plane isn't terribly accurate, but it's totally straightforward as to what it means, and will prompt the pilot to actually pull up the numbers.
 

trimtab

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It's been shown that rows of dials are pretty much the worst way to impart information to someone occupied with another task.
One might think so, right? I sure would.

And yet, there's data...and no amount of squinting can make the data agree.

The safety benefits of glass are tales we tell ourselves to liberate our wallets of their burdens, and perhaps even make things worse somehow.

The jury is out.
 

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BJC

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The safety benefits of glass are tales we tell ourselves to liberate our wallets of their burdens, and perhaps even make things worse somehow.
The primary determinant of flight safety is the attitude of the pilot. The type of instrumentation display has little to do with it.


BJC
 

Pops

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Takes you brain longer to process a number than the position of a needle. NASCAR cars have all needles at 12:00 when things are normal.
Wonder why one of the first indications of hypozemia is the lack of your ability to read numbers.
 
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