skyhawk Posted March 25, 2008 Share Posted March 25, 2008 hi guys, would it possible for a subdirectory for cool paramotor designs and inventions. I'm interested in making a motor but rather than just copy someone elses (isn't that what most of them are ?) I want to try and push the technology a bit and really find out what other pilots want from a motor. Wouldn't it be great to pick all the best ideas and combine them into a working motor. It might even have a few major players quaking in their boots lol. Quote Link to comment Share on other sites More sharing options...
gordon_dunn Posted March 25, 2008 Share Posted March 25, 2008 You'll find that a lot of the current manufacturers have collated all the 'best ideas' and combined them on their best machine, 'best ideas' is a very subjective matter. You really need to break it down and ask what you're trying to get out of it- a performance machine, or simply auxillary power for a paraglider. The general consensus is that you can do one of these well, but not both. The next revolution in paramotoring will be when someone puts aside every influence from what is currently out there, and looks at the core fundamentals- footlaunch, harness, wing attachment, thrust- along with consideration for weight, alternative to a dangerous prop, and costs. The PPG market is already very competitive, prices are very good- definitely a buyers market at the moment. It would be difficult to build a machine with the quality, features and performance of an H&E for example, for any less than the market price. Unless there was a quantum leap innovative idea, i wouldn't even consider a self build. GD Quote Link to comment Share on other sites More sharing options...
Guest Posted March 25, 2008 Share Posted March 25, 2008 (edited) I would start with what I dont like about paramotors as they are at present. Number one is the flying position. Sit up and beg. It presents huge drag, spoiling the LD ratio and it removes considerable control input from the pilot. Top of my wish list is a tilting harness that you can stand up in for landing and take offs but get into a proper flying position during the flight. Sounds easy but is extremely difficult to acheive. Constraints. 1. the hang points must remain at the hip or just above 2. the torque steer reduction of the swinging arm system must be retained 3. the prop disc must mainatin a near vertical alignment during transitions of pilot 4 airflow smoothing must be built into the design to maximise efficiency Gordon's statement "or simply auxillary power for a paraglider." has, at present, not in any way been achieved. Units are way too heavy and cumbersome and draggy and have poor pilot position. The closest I've seen yet is a motor from the Czeck republik called Airgate. Its a step towards but still a long way to go. I have one of these on order as a demonstartor so will see if it lives up to its promise. I know that my own use of paramotor is not everyones idea and many prefer the craft as a primarily motor driven machine. But I do think that many paraglider pilots who are not attracted to ppg would be if my wish list could be granted. It is really a matter of getting the geometry right with a simple system to extend the swinging arm and bring the hang point forward at half the distance that the pilots hang point moves forward???? I know what I mean. A little electric driven unit that has a harness like this and enough power for two or three boosts to cloud base would be a big seller to an as yet untapped market. Edited March 25, 2008 by Guest Quote Link to comment Share on other sites More sharing options...
gordon_dunn Posted March 25, 2008 Share Posted March 25, 2008 One 'blue sky' idea that would be an option would be a hydrogen peroxide powered device. This is similar to the 'Jet pack' technology, where thrust is generated by the catalytic reaction of hydrogen peroxide and silver. The silver decomposes the hydrogen peroxide into a mixture of superheated steam and oxygen in less than 1/10 of a millisecond, increasing it's volume up to 5000 times. This hot gas is used exclusively as the reaction mass and is directly led to one or more jet nozzles. Of course the jet pack requires a lot of thrust to lift a man vertically- the limitations of fuel supply mean that typical flights are only between 30 and 45 seconds- but if the reaction was slowed down, by reducing the amount of catalyist then you should get a more prolonged thrust duration- requireing only around 60kgs instead of 125kgs thrust. The reactor is very simple, there would be a requirement for very few moving parts, and thrust would be instantaneous- compared to a turbine or conventional two stroke unit. Such a concept would mean that there would be no prop, no cage, instant response to throttle, no pollutants, etc.... On the downside though- high expense of peroxide propellant, difficult to source propellant, danger of scalding- exhaust gases are 740 degrees C! Just an idea...... GD Quote Link to comment Share on other sites More sharing options...
pete_b Posted March 25, 2008 Share Posted March 25, 2008 One 'blue sky' idea that would be an option would be a hydrogen peroxide powered device. This is similar to the 'Jet pack' technology, where thrust is generated by the catalytic reaction of hydrogen peroxide and silver. The silver decomposes the hydrogen peroxide into a mixture of superheated steam and oxygen in less than 1/10 of a millisecond, increasing it's volume up to 5000 times. This hot gas is used exclusively as the reaction mass and is directly led to one or more jet nozzles. Of course the jet pack requires a lot of thrust to lift a man vertically- the limitations of fuel supply mean that typical flights are only between 30 and 45 seconds- but if the reaction was slowed down, by reducing the amount of catalyist then you should get a more prolonged thrust duration- requireing only around 60kgs instead of 125kgs thrust. The reactor is very simple, there would be a requirement for very few moving parts, and thrust would be instantaneous- compared to a turbine or conventional two stroke unit.Such a concept would mean that there would be no prop, no cage, instant response to throttle, no pollutants, etc.... On the downside though- high expense of peroxide propellant, difficult to source propellant, danger of scalding- exhaust gases are 740 degrees C! Just an idea...... GD Where would we be now with out ideas. Everything starts somewhere Pete b Quote Link to comment Share on other sites More sharing options...
norman Posted March 25, 2008 Share Posted March 25, 2008 The last people to use fuels like the ones you refer to had spectacular results. See my blog post here to get a peek of 'one they made earlier'. Quote Link to comment Share on other sites More sharing options...
gordon_dunn Posted March 25, 2008 Share Posted March 25, 2008 Pure hydrogen peroxide is relativley stable, but handling of the catalyst in it's presence needs to be careful. The jet pack is a very clever bit of engineering really, but it took a very skilled operator, and a lot of 'adrenalin' to actually fly it--- considering that if you haven't safely landed after 45 seconds, then you didn't have any option but to fall to the ground. As far as I'm aware there are only 3 trained operators in the world for this machine- although apparently Michaeal Jackson was a pilot at one point, and allegedly made a few public flights. GD Quote Link to comment Share on other sites More sharing options...
Guest Posted March 25, 2008 Share Posted March 25, 2008 (edited) Isnt there a beetle called the Bombadier Beetle that shoots a jet of flame as a defense mechanism? I seem to remember it having chambers of hydrogen peroxide and possibbly ammonia mixing in a tude with an enzyme catalyst? would that make a bang? Interesting to imagine how such a creature might evolve! Edited March 25, 2008 by Guest Quote Link to comment Share on other sites More sharing options...
gallar Posted March 25, 2008 Share Posted March 25, 2008 And the RN (technically successful) attempts at HTP propulsion systems resulted in the class concerned being unofficially renamed from the 'Explorer' to the 'Exploder' - with some reason! However, can certainly see the attractions of bringing together the current 'best of breed' elements (per the head of this thread) and developing them further - the synergies achieved when the current components were assembled may be different as a cumulative result of the individually possibly modest changes that have come about in those components. May still face a fair bit of further evolution before the next revolution point is reached. Just an aside thought but I wonder if the announcement of rotary engine paramotor series production to start spring 2009 might/will have an impact on second half sales of 'traditional' units in 2008? Quote Link to comment Share on other sites More sharing options...
Guest Posted March 25, 2008 Share Posted March 25, 2008 not ammonia but hydroquinone which is apparently ..... a major component in most photographic developers where, with the compound Metol, it reduces silver halides to elemental silver. so we are back to silver! It was there all the time in nature! Quote Link to comment Share on other sites More sharing options...
Guest Posted June 18, 2008 Share Posted June 18, 2008 I missed this thread until now... I am quite excited about Leci. or Electricity if your posh. The E-pac at the moment lasts around 40 mins..... Talking to a guy at the comp who works in the field in 3 years time the E-pac will outlast any current Petrol Paramotor (even the bailey 4) if the curve continues (at its current and historic rate), year 6 will see an E-pac lasting over 8 hours!!! THEN!!!!!!! you have to ask the question.... Where will Solar Fabric be in 6 years? Imagine 26 Square Meters of Solar Fabric sending a charge back in as you fly, very ineffective at todays standards but...6 - 12 - 20 years!!! Cant wait! so.... Leci is where I am at. SW Quote Link to comment Share on other sites More sharing options...
Guest Posted June 18, 2008 Share Posted June 18, 2008 Yes I agree. This is the way I can see me going just as soon as the endurance levels come up and the weights come down. I love the idea of coming off power and the prop just coming to a halt, better still if the prop folds. Then we need a redesign of the cage for some way of making it safe to operate without one at all. Quote Link to comment Share on other sites More sharing options...
Guest Posted June 18, 2008 Share Posted June 18, 2008 The weight of the current one is a little over 20KG SW Quote Link to comment Share on other sites More sharing options...
gallar Posted June 18, 2008 Share Posted June 18, 2008 The leccy issue of endurance is almost certainly going to be solved in the fairly near future, the one that will need a bit of a rethink is the second flight matter - refuelling. Safe recharge is currently considerably slower than heaving in a few gallons of jollop and does require some creative solutions to get connections to electricity either from a main supply, portable genny or some flavour of yoghurt-knitter approved renewable. Five years, ten years, yes the solar cell fabric, its the early years that perhaps need covering, plus the days flying under a reasonably high wall to wall overhead clag. Initially I suspect that the solution will consist of having several easily swappable battery packs, with the expense that entails. But..... perhaps the solution is not to store the leccy, simply to generate it as required with a fuel cell. At least allows for refuel with fairly portable hydrogen pressure tank in the back of the van, even if currently limited refuel options if landing out. And.... would one fit in the boot of the new Tesla I wonder (http://www.teslamotors.com/) Quote Link to comment Share on other sites More sharing options...
norman Posted June 19, 2008 Share Posted June 19, 2008 Maybe the combo that may emerge will be a distillation of the ideas above. Folding prop blade and outrigger technology will do away with a cage (and its drag) as the prop will be at the end of a shaft well behind the pilot. With an electric power source and the folding blade, it spins when you need it and stows when you don't with its outriggers banishing the danger of the prop when it can do its worse, and outrigger drag like a Crane in flight. Laid back in flight position is going to come from a animated frame such as the one Francis illustrated. You will merely need to lean back after the device has been unlocked and it will slew your body into the correct position. Folding blade props are already with us, titanium and other composites are here to animate the frame. What is required is a designer to bring it all together and batteries with the weight/capacity qualities to make the device viable. Add to the mix a hybrid motor/generator, solar fabric and space meals and you will only need to land to earn enough money to take off again.... or pay for your rig. Then the paraglider pilots will buy them by the truckload making PPG their Raison d'être (reason for being). This after all is merely following in the path of glass fibre sailplanes that have been self launching, motor or blade stowing for some time now. Well, 'tis an idea isn't it? Quote Link to comment Share on other sites More sharing options...
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