Would like to "fly around" just at or above ground effect-SLOWLY???

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Dana

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Jbaz, the problem with an aircraft designed to be flown very slow is that its entire speed range is very slow... all the speeds are very slow, including the wind speed it can handle. That's why all successful HPA flights have involved starting to set up the aircraft long before sunrise, making a quick flight just before sunrise, and [hopefully] getting the aircraft disassembled or hangared before the first breath of wind starts. Unfortunately, there's no way around it... very slow means very light, very light means not very strong, etc. Also in the desert, even if the wind isn't blowing hard, once thermal activity starts mid morning, it can get quite rowdy.

As others have said above, you can't beat a powered paraglider for low and slow flying, and a PPG is probably the safe lower limit for that kind of thing... about 20 mph flying speed. One advantage of a PPG over a slow airplane is that once you land, you can immediately collapse the wing and no longer worry about the wind picking your now empty airplane up like a feather and tumbling it away. However, unless on the shore where the air is smooth, even PPGs are typically flown in the morning before the sun starts to heat the ground and cause thermal activity, or in the evening after things settle down.

Here's some "low and slow" flying...

-Dana

I don't suffer from insanity. I enjoy every minute of it.
 
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JBAZ

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Svsu, I expected a fraction of respect from a"respected" member of this forum/community! As far as insult, re-read my thread, it was HE who insulted me!

Thanks for the ideas (the guys that actually offered some). To the rest of you all, "I am out! To find some ideas elsewhere!"

Happy Holidays friends.

JB;)
 

Dana

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Jbaz, I don't see that anybody here has insulted you. A bit condescending perhaps, perhaps more than a bit, but people here are trying to explain the impracticalities of what you're proposing to do. You may try to "find some ideas elsewhere", but you'll be hard pressed to find anyplace else on the internet with as knowledgeable and helpful a bunch of people as here... I hope you stay. If you choose not to listen when you don't get the answers you like, that's your problem.

Many people, especially young people (like, I'm guessing, yourself) get interested in aviation and have all sorts of ideas, without realizing that what they propose has been tried before, sometimes with bad results. The intelligent thing is to learn from what's been done before and build on that, not repeat mistakes or dead ends others have already run into.

-Dana

The difference between theory and practice is that, in theory, there is no difference between theory and practice, but in practice, there is.
 

TerryM76

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Tempe, AZ
I was not aware of any dry lake beds out here but I do have some friends that have a blast flying off the lake beds in California using truck towed light gliders. I believe there have been 2 examples of Mike Sandlin's GOAT involved. You might consider Mike Sandlin's Bloop design if you really have some wide open lake beds to fly in. I fly R/C too and sometimes use the open desert areas but have on occasion slammed into paloverde and mesquite trees during landings...I only use Elapor or Epo foam for open desert flying.

Terry

QUOTE=JBAZ;158821]Hi all, I am an avid rc modeler and have been interested in flying around low and slow. By this I mean at or above ground effect like the human powered airplanes do But, want to use an electric or gas low hp motor. I live in the AZ desert so would like to fly in the local dry lakebeds.

Has anyone seen/heard of thus kind of flying? Something like a half sized 90' HPA with small motor. I looked intonground effect (wigs) but they cruise quite fast, faster than many slow ultralights.

Thinking about cruising around no higher than I am willing to fall.
:ermm:[/QUOTE]
 

SVSUSteve

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Svsu, I expected a fraction of respect from a"respected" member of this forum/community! As far as insult, re-read my thread, it was HE who insulted me!

Thanks for the ideas (the guys that actually offered some). To the rest of you all, "I am out! To find some ideas elsewhere!"

Happy Holidays friends.

JB;)

If you want to be respected, then you need to earn it. If you go around demanding to be respected (as you just did) then you will probably develop a reputation for being an arrogant kid who thinks he is above everyone else. Listen, read and learn from those here more experienced than you. If you do that, respect for you will slowly grow. Happy holidays.
 

StarJar

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Ahh, circleing the wagons around the "respected forum member" to undo his well placed apology Bad Form Sir!:tired:
Well maybe he's just trying to show I have a good side. He put a "like" on my apology, so I don't think he's trying to undo it. And without being accussed of circling the wagons, HITC has contributed tons to this forum, as anyone knows who has been around this forum for awhile. Not just in knowledge, but in a helpful attitude.
 

Head in the clouds

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Ahh, circleing the wagons around the "respected forum member" to undo his well placed apology Bad Form Sir!:tired:
Good expression, about the wagons, that's not one you hear in Oz. I didn't mean my post like that though, it's just that I admire someone who has the good grace to apologize when they feel they've overstepped the mark. I can be a bit hot-headed on occasions and I know how hard it can be to man-up publicly and admit I was wrong. And I probably still owe quite a few apologies that I should have made - sorry everyone...

I can quite see why Star had a curly moment in this case, I was thinking the same way. Just lately we've had quite a stream of folks join up who have absolutely no knowledge of aircraft ops or structures and they're often young and full of enthusiasm but completely aviation naive, and quite confident that their new idea has never been considered before and of course it's the answer to all our prayers.

I think the members here have generally been very generous and patient, kindly spending their time to try and encourage but at the same time point out what won't work and also provide direction, trying to steer the new enthusiast in a direction which is practical and safe and might have some useful outcome.

Almost without exception the OP then starts to become arrogant and slightly abusive because as SVSUS has pointed out, the answers they got weren't what they wanted to hear. In fact they came here just to get endorsement of their pet scheme rather than to learn from the combined experience. The next outcome is predictable, the new arrival leaves the forum without further comment and those who posted trying to help simply wasted their own valuable time. More recently, and after offering a welcome, I have been adopting a back seat position and wait to see whether anything worthwhile is going to come of it, and whether the OP is willing to do their own research or just wants something handed to them on a plate. The object of the forum, after all, is for each of us to further our knowledge and we're not going to do that by spouting, we will only progress by listening and following research suggestions.

Unfortunately, and as has been discussed in other threads, the communication and inter-personal skills of some of today's youth leaves a lot to be desired especially in the impersonal surrounds of the internet, and that is surprising considering that most of these youngsters have been brought up with the net as their primary form of communication. It's not that long since I joined my first forum and I was surprised at how poor my communication was and looking back on it, the way I wrote was very dogmatic and arrogant. I have worked hard at trying to develop a more diplomatic turn of phrase and to do that I try to keep an 'image' in my mind of the person I am addressing, while I write.

I'm surprised that schools don't have netiquette classes, or if they do, that they're not more effective.

HAPPY CHRISTMAS EVERYONE AND A PROSPEROUS NEW YEAR (prosperous def. - more building and more flying)
 

Dana

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I'm surprised that schools don't have netiquette classes, or if they do, that they're not more effective.
Saw that and said, "wow, what a great idea!" Mentioned it to my daughter, who's a teacher, and she said they're beginning to offer such, usually as part of the health class.

-Dana

It did what? Well, it's not supposed to do that.
 

SVSUSteve

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Evansville, Indiana
Merry Christmas to you too HITC and everyone else. May we all have a better year ahead than the last and may we all learn from the mistakes, missteps and shortcomings of the past to achieve new heights. Fly safe and pass along my well wishes to your respective families. As always, my greatest wish is to not add anyone new to my database this year but I sit here writing this with the prospect of a trip too Canada for a crash looming over the holidays I should be sharing with my family. G_d bless each and everyone of you no matter how much we have butted heads, disagreed or argued on here in the past.
 

Detego

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May 29, 2012
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North America
... Merry Christmas
... I sit here writing this with the prospect of a trip too Canada
... for a crash looming over the holidays
... G_d bless each and everyone of you
... no matter how much we have butted heads, disagreed or argued on here in the past.

Yes, Yes - May everyone get the Big Goose they deserve, and another piece of coal for the fire. Please remember
to give generously this winter, as there may be many with 'Ground Effect Planes', that can use your help or design
critique. Please be careful of the Psychopathic Worshippers; and for G-D SAKE, be careful building and flying your
planes; especially those of you who have 'Ground Effect Planes', that look like UFO's. Be prosperous and multiple,
in the privacy of your own homes or cars. G_d bless us everyone, and Happy New Year 2013.

In the immortal words of Frank Zappa - "Watch out where the Huskies go and don't you eat that yellow snow."
 

ThadBeier

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Dec 28, 2010
Messages
79
Location
Los Angeles, California
Hi all, I am an avid rc modeler and have been interested in flying around low and slow. By this I mean at or above ground effect like the human powered airplanes do But, want to use an electric or gas low hp motor. I live in the AZ desert so would like to fly in the local dry lakebeds.

Has anyone seen/heard of thus kind of flying? Something like a half sized 90' HPA with small motor. I looked intonground effect (wigs) but they cruise quite fast, faster than many slow ultralights.

Thinking about cruising around no higher than I am willing to fall.
:ermm:
Well, while I agree that the plane that you're speaking of will not have much utility at all, it's an interesting design exercise.

One of the features of the plane is that it will only fly in ground effect, and it should be designed so that it can only fly in ground effect. Most WIGs do have the capability to fly if necessary, but we don't want to ever get higher than you're willing to fall.

I agree with others that something as light as a Gossamer Condor/Albatross/Penguin would be uselessly unwieldy. You don't want something that will blow away in a gust of wind, something that could be flown in something other than a dead calm. So, arbitrarily, I set the speed of the plane at 30 fps (about 20mph). Most crashes at 20mph shouldn't be too serious.

An interesting feature of this plane is that there may well be no difference between minimum and maximum speed, or almost none. The Curtiss Jenny was similar in that respect -- takeoff, climb, cruise, and landing speeds were all within a couple of miles per hour. If there was a substantial range of speeds, then pulling back on the stick would allow the plane to actually get some altitude -- we don't want that.

If the wing area was 324 ft, and the gross weight of the plane is 500 lbs, then with a 1.5 Cl we should be just about right at 30fps. We can build the plane super-light if the wing has a small aspect ratio and the engine is small (and you don't weigh too much!) I would do a reverse-delta wing like Lippisch's designs, with the trailing edge of the wing relatively close to and parallel to the ground. The wing should be thick, and generate a high Cl, as we don't have to worry much about induced drag this close to the ground. I'd put the wheels on the wingtips and one at the tail. The winglets should cant inward quite a bit because they have to provide all the dihedral effect.

The engine can be small, as you are flying slow. At 30fps and 500 lbs and an L/D of 10 (assuming that the induced drag is minimal) then we would only need about 5 hp of net power. I'd use a big prop with a big reduction gear to turn slowly -- I had an ultralight with a similar rig that produced 75 lbs of static thrust on just 15 hp -- let's say we had a 10 hp engine producing 50 lbs of thrust at 30fps. That's not hard to achieve at all.

Unlike Lippisch, I'd put the prop in the front, angled down to push as much air under the wing as possible to provide extra lift for takeoff and running just over the ground. When you crash, it's better to have the engine be in front of you than behind you, especially on this lightweight an airplane.

One of Lippisch's designs is here:

http://1.bp.blogspot.com/_oC8TwXe4PF0/TKgU3FwmSaI/AAAAAAAABNQ/YnCqYY7LTQQ/s1600/lip502.jpg

Here's my design...

foo.jpg
 
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