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Gliding


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Flapping Flight Dec. 6, 2017, 10 p.m. PST
@ExpAir
The good side of high wing loading is less wind dependency of the craft which maybe advantage when maneuvering betwin tall buildings.
Initially I was thinking about electric ducted fan powered delta wing which to takeoff vertically and then to transit to horizontal but with high angle of attack on cruise in order to utilize leading edge vortices ( they create a lot of lift) which will allow to keep horizontal speed relatively lower and to gain some efficiency ( in comparition with pure rotor crafts) but now with the brick blowing problem overhead tilting coaxial contra rotating rotor with some fancy silencing blade tips powered by Wankel engine seems to be much lighter and to require les powerfull downstream on takeoff /landings.

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ExpAir Dec. 6, 2017, 2:58 p.m. PST
Looking at the wing loading of an average ultralight aircraft vs the wing loading of my biplane, the comparison is awful. My wing loading comes in at between 100 and 200 times the wing loading of the ultralight. Sure I could counter a percentage of that with speed, but I cant have a seated pilot flying in the same way that Jetman flies, neither would I want to. Ideal speed for bumbling around or commuting would be anything from 5 knots to 30knots. 50knots is still ok but becomes less appealing with more and more wind buffet. And 50knots would only be the beginning of where my wings could start lifting significant weight, and that would certainly not be the most efficient speed. Gliding speed would just about be higher than my max comfortable cruise speed. With a speed range that is predominantly under the stall speed of the wing, up to a maximum that is only just around the stall speed is not a recipe for good flight. In fact its a recipe to set the pilot up for a nasty crash. The next step is to fly as fast as Jetman - but that defeats the commuting nature of the flight. Jetmans flight profile would be like taking a Boeing to travel 5km. So maybe I need a biplane jetman configuration with prone flight position

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ExpAir Dec. 5, 2017, 7:13 p.m. PST
Im also trying to think of a balloon system that might work - like what you were thinking about - maybe a car airbag system

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Ken Burner Dec. 5, 2017, 6:51 p.m. PST
I think a mast mounted ballistic chute would work for most rotary craft. You would want to be sure that once the 'chute was deployed that a thrust kill switch was activated. Otherwise, if power was suddenly restored, one might fly up into their own parachute.

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ExpAir Dec. 5, 2017, 6:32 p.m. PST
Been thinking about this a bit more, and wondering how anyone with rotors would deploy a ballistic chute successfully. Also - even more importantly, if anyone was actually planning to use a craft where they were knowingly operating without chutes or without enough altitude for chutes to deploy, is it legal or allowable? I would have thought there would be more emphasis on pilot survivability.

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ExpAir Nov. 27, 2017, 1:49 p.m. PST
No chance. Even if you were in freefall, and allowed a rotor to have ample time to wind up - you wont decelerate a 160 - 200kg machine from the fall speed to safe landing speed. But if you prove me wrong I owe you a coffee :)

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Ave Zoid Nov. 27, 2017, 1:44 p.m. PST
@ExpAir
I wouldn't say no. The smaller the blade, the less inertia it has, the more kinetic energy (RPM) it requires. So a reasonably high altitude combined with a reasonably high initial velocity might do the trick for the blade diameters close to 8.5 foot.

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ExpAir Nov. 27, 2017, 9:21 a.m. PST
@Ave Zoid
No. unless you use a rotor, with collective pitch, you will not autorotate, and if you have small rotors, the autorotation will have no effect. Even if you used the full 8.5 foot for rotor diameter, I suspect you stand no chance, the disc loading will just be too great.

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Ave Zoid Nov. 27, 2017, 7:28 a.m. PST
@ExpAir
But they can autorotate, can't they? Which means variable pitch and mechanic clutched drive, or contact disconnect in case of electric. Just like I've been telling - hobbyking like designs won't do.

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Ken Burner Nov. 26, 2017, 8:30 p.m. PST
@ExpAir
Very nice video, absolutely beautiful craft.

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ExpAir Nov. 26, 2017, 7:44 p.m. PST
after the stress of the chopper madness - settle back with a nice calm enjoyable flight.
https://www.youtube.com/watch?v=p3iE8FInNuc

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Ken Burner Nov. 26, 2017, 7:42 p.m. PST
Brings a question to my mind. NASCAR Teams bring a spare car to the races. Can we bring a spare aircraft to the Challenge Fly-Off? Or only spare parts like Footfall teams have extra players.

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Ken Burner Nov. 26, 2017, 7:34 p.m. PST
@ExpAir
Great video. Think I just found my pilot, I mean "operator" for the Challenge! Of course you have first dibs on him.

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ExpAir Nov. 26, 2017, 7:34 p.m. PST
if you survived the previous video - try this one.. I have never seen anything like this
https://www.youtube.com/watch?v=8e_9BHbMsSY

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Ken Burner Nov. 26, 2017, 7:27 p.m. PST
@ExpAir
Good point. On Mars, an air bag landing craft bounces and tumbles for several minute after landing. Guess if one meant to go bowling as I mentioned below, he could find himself at the pizza place way down the road. But hey, at least he arrived in style.

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ExpAir Nov. 26, 2017, 7:21 p.m. PST
Ken - talking about tumbling and flying ... check this out. It sort of twists my mind how this is even possible
https://www.youtube.com/watch?v=CcY54zQMIqg

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ExpAir Nov. 26, 2017, 7:03 p.m. PST
Ken, you ... and any of us ... would do well to test intended safety equipment well .... like for instance , build a trebuchet and launch an old tumble dryer into the air with intended safety equipment attached. Now you have a nice heavy device tumbling at speed. activate safety ..... and see if Jimmy the testdummy survives, and if your craft survives ....haha.
Don't launch tumble dryers towards neighbours :)

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Ken Burner Nov. 26, 2017, 7:01 p.m. PST
I see that I don't type/spell very well during football. Anyhow, Go-Fly allows unlimited altitude for the Challenge. So you could limit the "dead man's curve" area to take off and ascent, touch and go, and lastly descent and landing for the contest.

If these craft go into the mainstream and people use them to go a mile down the road to go bowling, safer systems need to be in place. Perhaps an air bag system like used on some Martian landings would work. They completely encompassed the crafts and they bounce and tumbled to rest on landing.

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Ken Burner Nov. 26, 2017, 6:44 p.m. PST
@Lazer
Yes safety at the alituted I expext the Flyy-Off to typlically flown is of much concern. My knowledge so far is that ballistic 'chutes aren't good for below 15-20 foot AGL. ExpAir and others have mentioned that my thoughts of retro rockets or air bags are dependent on the attitude of the craft when it contacts the ground. Straight down they can be made workable. Tumbling or with lateral motion contact, not so good.

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Ken Burner Nov. 26, 2017, 6:10 p.m. PST
@Lazer
As a pilot also, the thought of these vehicles, with rather inexperienced "operators," is a bit unnerving. My thought is that the PAV's won't, or perhaps not be allowed, to fly very high.

With that being said, the sky does belong to the people. Accordingly, the FAA will adapt and continue to provide safe air corridors to all.