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Long-range, Slow Low Flight Design(s) - 12/8/2002 10:21:50 PM   
john_89


 

Posts: 56
Joined: 12/2/2002
From: New Lisbon, WI, USA
Status: offline 		Am looking for a plane design that would give me long range capability, minimizing fuel usage. I think a sailplane is probably what best meets this criteria. But on the other hand, I need very slow flight capabability for surveilance of the local wildlife.I live in the midst of hundreds of thousands of acres of goverment wildlands. The design also needs to carry a few lbs of payload. This probably dictates a large model w/ 70+ inches of wingspan & large engine. Perhaps a weedwacker or Honda Micro engine would give the best fuel efficiency for this size. High speed is probably not even wanted but a 20MPH topspeed would be nice. At this point I'm looking at an auto-gyro or a lightplane w/ a very large wing-area. Like to find a ready-to-build kit that meets my needs. Please, any thoughts on where I need to go here. Thank You In Advance
       Post #: 1

Long-range, Slow Low Flight Design(s) - 12/8/2002 10:38:20 PM   
Dsegal


 

Posts: 1767
Joined: 10/20/2002
From: Philadelphia, PA, USA
Status: offline 		How about the Senior Telemaster at http://www.hobby-lobby.com/srtele.htm/

Dave Segal

(in reply to john_89)
       Post #: 2

Long-range, Slow Low Flight Design(s) - 12/8/2002 11:07:07 PM   
BMatthews



Posts: 8956
Joined: 10/4/2002
From: Burnaby, BC, CANADA
Status: offline 		John, you've never had much to do with model airplanes in the past have you. There are just too many of the items in your requirements that are contradictory and that indicates to me that you're brand new to all this.

First off, it sounds like you plan to use this as an aerial observation post for birds or ground based wildlife. Much like a civilianized UAV. You should realize that the requirements for flying the model don't leave much or any time for rubbernecking at a monitor. Also the range is not as far as you may think. The modern radios are very good but you still need to SEE the model with enough detail to fly it or it will just crash. Model autopilots that allow the model to range out beyond visual range and return are far from mainstream, off the shelf items.

If I'm off base here and all you want is a camera carrying model that can range out 1/4 mile or so from where you park your car then I apoligise. If this is indeed the case how about some more description of the following;
[list=1]
  • what are the parameters for flight duration?
  • What are the takeoff and landing areas like? We need to know how long the clear area is and how tall the trees are on the edges of these clear areas and what the ground conditions are in these areas.
  • What sort of camera are you intending on carrying? Are you wanting to transmit the video back to yourself or record in the model?
  • What model flying experience do you have? If none, as I suspect, are you willing to spend the time to learn?
    [/list=1]

    Just off the top of my head I'd say the easiest solution for your needs would be a larger set of glider wings mounted on a new custom designed fuselage. This would be a larger pod like thing with a large cargo area in the center just under the wing to allow the camera to be aimed prior to takeoff in different directions. There would be no landing gear. Instead you would hand launch it and then land it in the clearing near you. A hardended shock absorbing belly skid would slide over the expected rough ground soaking up the landing shocks and hopefully bounce over any rocks rather than smacking into them. Flaps on the wing would slow the model for landing and control the glide path.

    This sort of model is fairly easy to learn to fly but it sounds like you will have very tight landing spots and landings is where the wheat is separated from the chaff. Spot landings in tight places will tax your skills. You'll need to be very comfortable with the model and your flying skill to do this time after time with no damage. This takes practice. Probably in the order of 50 to 60 hours of specific landing practice.


    _____________________________

    Bruce-
    Proudly wasting balsa since 1965.

    Free Flighters go that extra mile........

    (in reply to john_89)
    •        Post #: 3

    Long-range, Slow Low Flight Design(s) - 12/9/2002 2:34:28 AM   
    Ollie


     

    Posts: 958
    Joined: 12/8/2001
    From: Punta Gorda, FL
    Status: offline     		If you want to be able to operate in areas without a clear landing strip, you may want to resort to a landing net with a lightweight frame about the size of a soccer goal and just fly the model into the net at low speed. When combined with hand launching, this will give you the greatest operational versitility. You not only want to be able to fly slowly but, I assume you want to be able to operate in the wind. This suggests an operational airspeed range of about 15 to 30 MPH. You need enough wing area to limit the wing loading to about one pound per square foot for slow airspeed and enough power to achieve an airspeed of about 30 MPH.The Senior Telemaster at 8 feet of span might do the job. See:
    http://www.hobby-lobby.com/srtele.htm

    At one time, there was a 12 foot span Telemaster available but I haven't seen it advertised lately. If your eyesight is good enough, you might have a visual range of a third or even a half mile with the 12 foot Telemaster.

    _____________________________

    Regards, Ollie

    (in reply to john_89)
           Post #: 4

    Long-range, Slow Low Flight Design(s) - 12/9/2002 10:58:59 AM   
    William Robison



    Posts: 20269
    Joined: 11/10/2002
    From: Mary Esther, Florida, FL, USA
    Status: offline     		John:

    There is one airplane that was designed to carry cameras and etc. That is the Bruce Tharp "Flyin' King."

    [url]www.btemodels.com/flyin_king.html[/url]

    Price is $159, including freight to your door.

    Since the FK is "Only" 80" wing span you might prefer the "Super Flyin' King" with 132" span. It is intended for a gasoline engine, that means longer flights than a glow engine with the same amount of fuel. Not only will it carry more weight (which means more fuel and endurance) the larger size would let you see it well enough to fly at greater distances with safety. As Ollie said, maybe a half mile away. But you must have a field to fly from.

    Check it out.

    But if you want to be king, a twin is the thing.

    Bill.

    (in reply to john_89)
           Post #: 5

    Long-range, Slow Low Flight Design(s) - 12/9/2002 12:28:48 PM   
    john_89


     

    Posts: 56
    Joined: 12/2/2002
    From: New Lisbon, WI, USA
    Status: offline     		B from B.C., you are absolutely right about my inexperience. A number of my ham friends are RC plane drivers. 1 friend seems enthusiastic about getting me on the runway to learn w/ 1 of his handbuilt planes. After reading 1 website for beginners, I am remiss to use anything but a rubber model on my maiden voyage. I am so inexperienced I haven't even driven an RC car! So it looks like I've got a good 50-60 hrs of training time & probably more than 1 crash in my future. Am very dedicated to making this happen. What I want B is to create & fly a remotely piloted vehicle (RPV). The ham license will allow me to do things to greatly extend the range of control radios & wireless cams. Have spent the majority of my research time looking for any type of self-stabilizing, hovering VTOL aircraft design w/ miles of range to make the RPV livecam project much easier. Conclusion; there are non. Dragonfly III was the original "dreammaker". Much more to discuss. Be back tommorrow.

    (in reply to john_89)
           Post #: 6

    Long-range, Slow Low Flight Design(s) - 12/9/2002 1:46:36 PM   
    BMatthews



    Posts: 8956
    Joined: 10/4/2002
    From: Burnaby, BC, CANADA
    Status: offline     		Well John, you're at the beginning of a long and adventerous journey. Good to have you aboard. And good luck on your quest. To tell the truth I sort of thought that this was another of those "I want to start with a 4 engine B17 that drops bombs and still does all the stunts...... and by the way, I'm going to teach myself to fly it all alone" stories.

    That Senior Telemaster that DSegal mentioned is a great trainer and would serve you well as a test bed for future mods and tests. Don't think of it as the last model that you'll ever build for this project but it's a great start. And with a bit of help from your buddy there's no reason why it can't serve you well for many years.

    A few years back there was a video I saw about another HAM that did something like you're going to do. He had a van set up with a stronger transmitter than we usually use and the model was equipped with onboard video. He would take off normally and then step into the van and continue to fly using the video. To help out he also had an onboard transmitter that sent back info on the model's heading and altitude. Added to that the van used an array of antenna's for directional finding so he had a bearing on the direction to the model. By using these two he always knew where the model was and what direction it was heading. He had many flights where the model got 2 or 3 miles away from the van and returned succesfully. In one part of the video he was actually above the clouds and completley out of sight of the van yet using the two bearings he was able to direct the model back to the van and land like it was nothing.

    Of course nowadays with GPS data cards so easily available I would think it's much more possible to set up a model that would fly itself even for a serious hobbiest. Of course you'd need some other stuff to fill out the onboard Autopilot but the building blocks are all there and just need someone that can produce the onboard controller. In the old days Maynard Hill (a noted modeller with many world records to his credit) set up an autopilot using electrostatic sensors to control one of his models so the piloting duties would be less while going for a distance or altitude record. Nowadays I can see how with the GPS data and some gyros (RC helicopter stuff) a person could make a model that would use all the data to determine what the model was doing rather than having to rely on other more difficult to use stuff.

    Anyway, all that's for the future. Even if you get your model to fly where you want for how long you want it'll still be YOU taking off and landing...... at least for the first generation of "The Project". So you still need to take that all important first step. I'd go for that Telemaster. It's a great trainer and as I said before it's got the load carrying capacity to accomodate the first developments as you begin experimenting.

    In the meantime check out the Flying Model Simulator software. Do a search on "fms download" and it'll come up I'm sure. It's not totally accurate but it's a start. And with winter almost upon us......

    PS: that Flying King looks pretty good as well. Probably wouldn't be a bad trainer either. It's certainly got the wing area to haul up some extra gear.


    _____________________________

    Bruce-
    Proudly wasting balsa since 1965.

    Free Flighters go that extra mile........

    (in reply to john_89)
           Post #: 7

    Long-range, Slow Low Flight Design(s) - 12/9/2002 2:32:37 PM   
    William Robison



    Posts: 20269
    Joined: 11/10/2002
    From: Mary Esther, Florida, FL, USA
    Status: offline     		Bruce:

    The Senior Telemaster is a great airplane. It's big and light. It's so light that even with its 8 foot span it flies well with a .40 engine. With a .91 four stroke it would probably handle a lot of extra weight in fuel and camera gear.

    But I fear that its lightness woud also be its downfall if operated in gusty air with much of a camera on board. as light as it is I'd worry about structural failure from wind induces overloading. Steady wind, no problem.

    With a .61 two stroke he'd be a bit lighter, but the .61 wouldn't swing as big a prop, and he'd have to leave something home. The 61 2s' fuel rate would probably be as high as the 4s' fuel rate, so he'd still need the ame size tank.

    All in all, I think the FK or the Super Flyn' King would be the better choice as they are designed to be weight haulers.

    A twin Flyin' King is a much better thing.

    Bill.

    (in reply to john_89)
           Post #: 8

    Long-range, Slow Low Flight Design(s) - 12/9/2002 7:27:53 PM   
    john_89


     

    Posts: 56
    Joined: 12/2/2002
    From: New Lisbon, WI, USA
    Status: offline     		Hey Guys Boy its cold outside this morning. Heard the trees popping around the house from the cold last night. Be a great day to fly an RPV & be outside while in. Don't know how a Honda Micro 4 stroke would perform. Probably w/ considerable power gain but reduced fuel efficiency & range as all internal combustion engines w/o a preheat on the intake do in cold dense air. Bruce you're probably the 3rd Bruce I've communicated w/ on the net from B.C.! What a small world, I tell ya. Used to talk often w/ Vancouverites on the10 meter band on a CB antenna stuck to the freezer in the basement. A bandpath would always open to that area in the late afternoon. Also let me compliment you on the closest-to-Heaven scenery I've come across; Yoho & Glacier National Parks. Unbelieveable. Been allot of places now, but nothing tops that in the category of "most spectacular". It seems 1 of the things that RPV & UAVers obsess over is altitude & horizon lock. It seems that doing this manually while only seeing through a "camera-staw" is a difficult task. Only 1 RPV camphoto that I've seen on the net actually had artificial horizon lines in a "heads up" type display. Everyone else just seems to use GPS coordinates, altitude, & speed overlays. Must be they are orienting by "straw" sight. A stable aircraft design is probably a great help here. The RPV designs I've seen & read use a twin boom tail w/ a pusher prop mounted between the booms. Are the aircraft being recommended here, of that style? Couldn't get a visual download on the Telemaster. This is where I felt the Dragonfly III w/ its 4 rotors mounted on the ends of 2 crossing spars would make the whole flight thing much easier. From the demonstration I saw, it seems that in order to get the Dragonfly to standstill & hover 1 just needs to let go of the controls. Wouldn't that be nice, but that system works w/ 4 individual electric motors. Accomplishing this w/ a stronger, longer ranging fuel burning engine & the necessary chain drives or gears would be a whole other engineering feat. Beyond my skills! 1 ? keeps coming to mind; how do I hand launch an 8' or 12' model? Have thought of using a jetsoning parachute & flight controls for some type of VSTOL landing. W/o using a public road, I have no real airstrip. A 100' down the driveway w/ trees & highline at the end. Someone somewhere mentioned using a plywood launching ramp for a VSTOL takeoff. That would work in the backyard as I have a good clearing above low brush. 1 last thought, Bruce. Wouldn't an RPV/UAV be a great tool in the hunt for Sasquatch. Be Back Later

    (in reply to john_89)
           Post #: 9

    Long-range, Slow Low Flight Design(s) - 12/9/2002 11:25:21 PM   
    BMatthews



    Posts: 8956
    Joined: 10/4/2002
    From: Burnaby, BC, CANADA
    Status: offline     		Will, yeah it's light alright. Perhaps too light for gusty winds in stock form but weight is weight whether it's in the model's structure or in the cargo bay. Once there's a couple of extra pounds of load on board it would settle down nicely. Probably want to build it up with some spar mods to take the intended load for later though. Depending on the size of the UAV components the fuselage might be a little small for later so the King may be the better model for that.

    John, the models mentioned so far are all a conventional layout with the engine in the nose. If you want a clear camera view you'd have to find something else. I don't know of any kits that fit the center pod pusher layout. But that's not going to be your first model anyway. You've got to crawl before you walk. I honestly feel that you'll only be successful with setting up the autopilot is you fully appreciate the skills involved. For example, it's normal to start leveling out from a turn before you actually have reached the bearing that you intend to fly. If the turn is maintained fully until that time and then the model is commanded to level out it WILL overshoot and then have to hunt back to the intended heading. This could easily set up some nasty oscillations and lead to motion sickness on your part looking at the monitor........

    Also I'd drop the Honda engine idea. With the size and weights of the current gyros, GPS OEM boards and the like there's absolutley no reason why your UAV can't be fully functional with model airplane level technology. Forget the weedwacker engines and gear drives. That level of power and relative complexity is only needed for military level payloads. A model airplane 90 size engine will easily handle a 100 inch model that weighs 12 lbs. The weed wacker options would need to be at least that large just to carry the engine, let alone the rest of the stuff. Takeoff and landings in your yard as you describe it is a different matter. You WOULD have to break out the chainsaw for this size of model.

    How about thinking small? With the size and weight of the board level cameras and the other stuff I would think that a 6 ft span 25 engine model is doable. The only thing that would suffer may be the overall duration. An hour is practical but more than that and the fuel load considerations become major. Both for carrying that much and for delivering it to the engine properley. But at 30 or so mph that's still a 15 mile range. Plenty far enough for the transmitter to work over reliably. Certainly far enough that the model based reciever and transmitter would need some help.

    Small like this can easily be handlaunched. And the recovery can be done using the shock absorbing belly skid I mentioned earlier or Ollie's excellent catch net idea.


    _____________________________

    Bruce-
    Proudly wasting balsa since 1965.

    Free Flighters go that extra mile........

    (in reply to john_89)
           Post #: 10

    Long-range, Slow Low Flight Design(s) - 12/10/2002 12:24:33 AM   
    William Robison



    Posts: 20269
    Joined: 11/10/2002
    From: Mary Esther, Florida, FL, USA
    Status: offline     		Bruce:

    Of course the Sr. Telemaster could be reinforced. Note John's apparrent skill level. How would he know where to add what for the necessary reinforcement? The FK already has the strength. It's just a simpler solution, in my mind.

    The "Straw View" syndrome has an easy solution when using a conventional airframe. Put the camera in the cockpit, having the top of the engine cowling in the bottom of the picture, and with a short focal length taking lens you can have a view extending 50 degrees to either side. This requires a LARGE monitor for a good view. Better method is three cameras with their views barely overlapping, one pointed straight ahead and one to each side. Then you use three monitors - Virtual cockpit! And much better resolution than the single camera/wide lens system. The three signals could either br multiplexed on a single xmit frequency, or as light as they are, three separate transmitters could be used. The latter would be a lot better, IMHO, redundancy gives more reliability. What if he goes out of visual range and his video system quits? With the triple (or just doubled) system he has a safety.

    John:

    A parachute landing would be easy. Haven't seen it for a while, but a packaged system was advertised a few years ago as a safety device for new pilots - lose control, pop the 'chute, live to fly another day.

    Catapult launching is common, sounds like you will need it. The "Whiplash" is normally launched with a cat. Check it out at [url]www.aerojetmodels.com[/url] click on "Whiplash."

    With the catapult/parachute method you could eliminate the normal landing gear, but the plane would have to withstand the accelleration loads of the cat - so the longer the ramps the better, lets you use lower accelleration rates.

    But the longer the cat the heavier, and the more difficult to drag it around to point into the wind.

    Ever consider a helicopter? Of course they are a lot harder to fly, acquisution cost would skyrocket, and you can figure on maintenance time to be equal or greater than flight time. And a system failure would probably lose the whole thing instead of leaving something to rebuild from. However, a three axis gyro system would make it fly rock solid and then it would be easier to fly than fixed wing. Until something broke. I have one heli with a three axis gyro set-up, turned a vicious monster into a kitten.

    Down and dirty suggestion: If you just want to get into radio controlled flight, get something small that you can hand launch, or sized to your available "Flying field" and enjoy it. If your are really looking for aerial surveillance it's going to be major money, and probably expensive development before you have a reliable system.

    Think about it. Bigger flies better, but smaller is a hell of a lot cheaper.

    Twin your balloon, fly to the moon.

    Bill.

    PS: For fixed wing or helicopter the FMA "Co-pilot" is a great stability augmentation device. WR.

    < Message edited by William Robison -- Dec 9 2002 7:34PM >

    (in reply to john_89)
           Post #: 11

    Long-range, Slow Low Flight Design(s) - 12/10/2002 12:32:13 AM   
    john_89


     

    Posts: 56
    Joined: 12/2/2002
    From: New Lisbon, WI, USA
    Status: offline     		I'm not sure how a tractor(pulling)prop will affect the cam's vision. B it sounds as if you're kind of dry to the idea of hand launching & net catching 1 of these monsters. What do you think of the parachute idea. Launchable chutes are available. My ideas about the Honda engines came from people already operating long distance RPVs w/ flight durations in excess of an hour. It seems that these utility engines are quieter & more fuel efficient than the model engines. W/ better fuel economy comes longer loiter times for working search grids. A quiet engine is certainly preferrable for nature observation. More than likely its going to be hard, though, to get any of these engines to operate w/o being heard 1/2 mile away. Certainly not going to be as quiet as a regular automobile. The weight of a 21cc Honda Micro might be prohobitive. Also the statement about fuel economy, might have been based on experience w/ 2-stroke & not 4 stroke model engines. I already see there are techniques for improving efficiency w/ these engines. I was just reading that installing a higher pitch prop had allowed 1 modeler to improve fuel efficiency, engine life,reduce noise, & improve agility. It seems that by slowing the prop down his model was much less skidish. On the other hand just a little more pitch had degraded performance. Have to go to the large engine forum to find out what works & what doesn't. Hoping to achieve flight distances of 5-7 miles roundtrip. 20 miles would be outstanding. Multi-element-directional beams are a must to provide radio links at this distance. I understand that as an amateur I can hook the 72 Mhz control radio to an outboarded antenna. W/ 750 milliwatts of power on a beam, I should have a solid link to that reciever even 20 miles out. I mention gears only because I was thinking of how a four-bladed rotorcraft might be powered by 1 engine. Obviously a no-go idea. But until ideas are eliminated the sky is the limit! How difficult do you guys think that maintaining stable level flight is going to be? Am hoping that I could set the plane to fly level & straight & then watch a 2nd cam pointed at the ground w/ only an occasional glance at the flight control cam. Having some type of altitude display readout is a must, I think. What do you think will the model be stable enough in low wind conditions that I ca