Russian paramotors

[Yarich]

Hi all!

Want to talk a little bit about differents in russian and europe paramotors. You see almost all paramotors which are produced in Russia has specific points of fastening for risers. See like this http://paraplandv.ru/forum/download.php?id=2661 and http://paraplan.irkutsk.ru/images/image ... t=Пуховый__комбинезон__с__полуторным__количеством__пуха.

This makes unreal to control you glider with your weight, because of solid fastening.

Do you have in UK the same paramotors?

[Guest]

Fixed high J bars went out of fashion here a long time ago. The closest we have is the soft floating J bars used by Fresh Breeze which can still allow a certain amount of weight shift control. High hang points are still dominant in the US but Europe has largely embraced low hang points with a particular preference for active swing arms.

[Yarich]

Only Fashion? some say that high J bars are better in turbulence. Why do UK refuse them, but US still use it? any opinions?

And what is the differents between FreshBreeze hang system and low hang points?

I'am thinking to change my J bar something on like snap100 hang points Or feshbreeze. I want to control my glider with my weight, like I do it in PG flight.

Thanks for you answer

[Guest]

The best way is to think of it like a Harley Davidson, (high hang point)

or a Yamaha R1 (low hang point)

Or if your a car person....

A Ford Transit Van (high hang point)

or an Arial Atom (low hang point)

Well thats my take anyway

SW

[Guest]

The closest you will get to a free flying feel is to go to a low hang point set up with active swing arms. Not identical but the closest at present that is commercially viable. Francis may have something to add here with regard to the Mantis design.

[Guest]

Yes.... Mantis started out with a brief to get a paraglider feel to the harness, more laid back and with body roll weight shift. The unit they sent me to try had a more rigid system. I have asked them why they changed and could they please send the older system. They responded that I was the first person to have shown interest in their original design brief and are sending the system for me to try on the unit I have. Watch this space.

As far as the system they sent with the unit? standard high hang point on the webbing with wicked torque effect with a cross strap to lift one side of the seat board (very uncomfortable).

Re floating J bars, I tried these on a fresh breeze that a student brought to learn on. I found that I could make a weight shift turn to the left on a full power climb; I used crossing the legs and the seat board was wider than my hips so I could slide across. Meaning that torque effect is compeletly overcome on this system. I do not know if it is just that set up or if floating J bars all work this well. I found them to be at least as effective as swinging arms. The down side for me was the height at which the brake handles sit; much too far away for comfort or to be like a PG

None of these systems can give as much weight shift as a PG harness until the pilot is laid back further so can roll the body rather than just leaning or crossing legs.

Also the distribution of the weight of the pilot and motor and the upright sitting position means that brake handles are much further back than in a PG harness.

Are high hang points more stable than low ones? I think this is an illusion. Yes you feel less chucked about but is that good? you are the pendulum in the "pendulum stability concept" so high hang points let you swing symetrically but you also need to load each side of the wing differently as the wing twists and rolls in turbulence and high hangers limit this. On a low hang point you will feel more movement but this may well be a Good Thing (I think this might be particularly true on a Revolution and so by extrapolation other reflex wings?, my recent limited experience on a Revolution leads me to say this but I am no expert in this type of wing).

I suppose if you want to just sit there and take it fixed High hang point would be better. If you want to pilot your way through a system that lets you weight shift (ususally low hang swining arms but also possibly high "floating" J bars.

As far as changing existing high fixed J bars for another system? Best sell the old and buy new, but floating J bars would be the easiest to retro-fit to the machine in the photo.

[Yarich]

Simon very good humour the variant with bikes is more pretty.

Francis, thank you for good explanation. Thank you for your advice too. But Iam a 20years old student and it is unreal for me to buy new paramotor. This year I need to buy a new wing. maybe next year I will order new cage and frame from titanium.

But when I said about controling glider with my weight I didnt mean excatly like in pg. I dont want to fly on paramotor laying back.

About collapse. usually when i do wingovers i finish it with spiral. But once I began to kill energy gradualy doing wingovers. When wingovers was not so big I feel relax and made mistake. my left ear coolapsed(assymetrick tuck) and I noticed that it was much difficult and longer to restore the shape of glider when just PG. I couldnt aply the weight to stop turning. Only brake control. I thaght If collapse was with my right part of glider I would not be able awoid twist because of torque.

These are my thaughts.

One more question. Is it easier to start with paramotor which have uper J bars?

[Guest]

Francis, thank you for good explanation. Thank you for your advice too. But Iam a 20years old student and it is unreal for me to buy new paramotor. This year I need to buy a new wing. maybe next year I will order new cage and frame from titanium.

of course it is difficult when money is tight. I really meant to be carefull when making modifications to existing machines. Research it carefully. Getting a new cage with a different system and using your existing engine is a good compromise.

But when I said about controling glider with my weight I didnt mean excatly like in pg. I dont want to fly on paramotor laying back.

Unless you are reclined like a PG harnes you will never get the same roll authority. It is exactly for this reason that you find the problems you tell of in your next sentence.

About collapse. usually when i do wingovers i finish it with spiral. But once I began to kill energy gradualy doing wingovers. When wingovers was not so big I feel relax and made mistake. my left ear coolapsed(assymetrick tuck) and I noticed that it was much difficult and longer to restore the shape of glider when just PG.

you have answered your own question. You do not have the roll authrity to give the correct control input. You need to be able to roll to the "good side". This increases trhe pressure in that side which flows across the cells to reinflate the collapsed side. Without this you rely on only the fowrad movement to re-inflate it so it takes much longer.

I couldnt aply the weight to stop turning. Only brake control. I thaght If collapse was with my right part of glider I would not be able awoid twist because of torque.

And your conclusion from this is?......

That to fly such radical manouvers on a machine that you cannot fully control is not so clever?

These are just my thoughts.

One more question. Is it easier to start with paramotor which have uper J bars?

Fixed J bars like yours? I find it harder to launch this machine because the pull comes from my shoulders not my hips, I cannot get my weight onto the risers until it is overhead, so can get pulled backwards a long way in stronger winds and it puts much strain on my back. In light winds with a forward launch it is the same because I hold the risers over my shoulders in a "low hanger" machine.

You may find that you can modify your machine to use "floating J bars" this will not make much difference to the launch but will give you much more roll authority with weight shift.

In the UK we have seen fatal accident with loading the machine in a spiral dive. Shackles snapping and swinging arms bending. I think if you want to do acro it is better without a motor, they are just not strong enough.

[Yarich]

Could you please explain more clearly why did it hapened? "In the UK we have seen fatal accident with loading the machine in a spiral dive"

I dont do acro. I think wingovers to 45degrees & spiral <15ms arent acro element. Doing wingovers means that you know the dynamic of your wing and cn control it. This will help when you fly in thermals.

But in fact you are right. This is not safe to do wingovers on paramotor like I have. But it is possible. I did wingovers many time, but once had mistake and I stopped.

[Yarich]

Could you please explain more clearly why did it hapened? "In the UK we have seen fatal accident with loading the machine in a spiral dive"

ok. I've understood. Had he reserve?

[Guest]

His own machine had a reserve fitted but on this occasion he was flying another machine which did not have one.

[dantheman]

AAIB bulletin here

Examination of components from several other paramotors has revealed distortion or damage to the horizontal arms, parts of the arms, or fittings attached to and applying loading to the arms. Such distortion indicates that these components have been loaded close to their failure stress levels.

Accordingly, all pilots are advised to refrain from extreme manoeuvres until the structural integrity of these machines is ascertained.

[Guest]

Vibration is a major issue and one that will play an increasing role in the coming years as machines become older.

Not just nuts and bolts loosening (we can spot this) but vibration fatigue. the welding of frames and structural components is at high risk. It is very hard to see cracks especially if thay are coming from the inside outwards. Our machines are often not welded using aircraft grade materials or accredited welders, we have no idea of the quality of our welded components.

If anything breaks during smooth level flight we can probably(?) stay in control and land safely or deploy our reserve effectively. This changes when something breaks in a radical manouver (anything more than 1.5 g in my view). a sudden lengthening of one side of the system and the ensuing cascade is very difficult to control and escape and the g loading on the pilot can make reserve deployment difficult or impossible. (ventral reserve is easiest to get out in high g)

I beleive DULV certified motors have to have been welded by aircraft certified welders? so machines for the german market. But without an annual CofA and some sort of fatigue and stress measurement we rely on our own ability to spot problems and also on luck.

[Guest]

the welding of frames and structural components is at high risk. It is very hard to see cracks especially if thay are coming from the inside outwards. Our machines are often not welded using aircraft grade materials or accredited welders, we have no idea of the quality of our welded components.

I would just like to confirm 100% that all Parajets have been made using Aircraft Grade Alloy (or Titanium) and ALL of the welding has been carried out by accredited welders.

SW

[chris]

Hi Simon,

Can you tell me out of curiosity, what grade of aluminium Parajet use, and what do you mean by an "acredited" welder?

Chris

[Guest]

Tis 7020 alloy I think..

I know that our welder has a ticket to weld Aircraft that's about it.

Please do call Markus for full info 08700 11 66 18

I though you would have mended Normans enough times to have sussed out the alloy LOL

SW

[Yarich]

Could someone tell me please an web site of any company who sells harness and cage with swingin arms for simonini mini2?

It would me nice, if you also help to find not expansive cage...

Thank you.

[Guest]

TP Propeller in Thailand made a frame and cage for someone I know for £270. They can also supply a harness as well. They will make the setup to your requirements.