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`Hi everyone. Newbie here in leicestershire already started ground training. What kit should i be looking for at getting me airbourne at 15 plus stone? Not got alot of money to throw at it but will stretch for the right kit.Have heard that you need to get it right or you will be constantly changing due to not enough power. gazz.

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Hi Gazz,

I'm learning too so not sure if I can advise on kit.

I would say that size of the prop is a factor in thrust, so don't forget to look into this aspect not just engine size.

The problem with starting out in this sport is that people won't lend you their kit so you can have a try on some differtn machines 'cos if you fall over and snap a prop or bend a cage it can be expensive.

Even schools like Airways, (which is probably the nearest school) where you fly their machines when you learn will charge you to replace a prop if you have a tumble.

Your best bet is to speak to as many dealers, pilots and instructers as you can, and you'll get a broad range of advice. It's not easy to get impartial advice, but there are lots of pilots in Leicestershire.

I'm in Leics too (Quorn), so get in touch if you fancy a ground handling session and/or a beer.

Cheers,

Mike

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:) `Hi Mike. Thanks for the reply.You are right in your reply on all fronts! Im being taught ground handling at the moment at our club site airstrip.Not finding it too difficult at the moment,although the wind is playing a big factor in when i can nip to airfield and have ago :x Keep in touch mate,and pop along to us sometime if you need a field im sure the guys will make you welcome when they are there and can get airbourne :roll: gazz.
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And smaller tri bladed props are less efficent, heavier and not welcome at some sites due to the noise they make from the engines over revving and from the props themselves.

A well balanced 125cm carbon fibre such as the Pulse prop ON THE CORRECT FINAL DRIVE is a good choice. On quality low hang point units with the correct offset there is no torque effect to counter act at all.

Felius ... -. .-.---

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And smaller tri bladed props are less efficent, heavier and not welcome at some sites due to the noise they make from the engines over revving and from the props themselves.

Felius ... -. .-.---

Odd you should say that as I have recently aquired a very accurate DB meter and will soon be producing a spread sheet with the exact noise levels in DB of each paramotor on tick over and during a take off run.

I already know your statment is incorrect from the little information I have already from 5 paramotors.

Sorry to be blunt but I have the proof and will display it in full when I have a few more paramotors to add to the list.

Whos sites have banned them? not a PMC site I hope?

SW :D

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This is a topic that fascinates me somewhat. Types of prop at different gearing, noise and efficiency, torque steer too. Like to participate if we get the chance. Certainly like to know what mines chucking out anyway, compared to the same motor that hasn't had ceramic fibre tape wrapped around the silencer. I can tell the note is deeper but would like to discover wether it's actually quieter.

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Ah a subject I know a little about!

Db meters have different weighting C or A most common. C looks at all frequencies and A looks at what our ears are more sensitive to.

Hi frequencies drop off faster with distance.

You will have to be exactley the same distance at each take off or unfair.

Not all paramotors need full revs for take off so how do you judge max rev noise?

Measure max revs on the ground?

Sound travels further in different temps, humidities and altitudes.

Noise travels further with the wind. Db meter should be placed in the same orientation to the take off and wind direction.

Walls and bulidings will refect sound making some frequencies louder and having a cancelling effect on others.

And finally sound is subjective. Each one of us finds different frequencies more offensive than others. Babies cry at a particular frequency not by chance!

Even though 2 paramotors may meter the same, the one with the higher pitch will appear to be more noisy. (back to the babies crying).

Still take it all with a pinch of salt and the tests will give us an idea.

Mikey

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Cheers Mike,

I have a type A good to 130db (hope it's enough LOL) and it says it's accurate to 0.05 of a db, but as you say, distance 'and I recon wind direction' is vital for this one.

If anyone would like their motor 'sound tested' please pop down with it so we can add it to the list.

SW :D

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This is a topic that fascinates me somewhat. Types of prop at different gearing, noise and efficiency, torque steer too. Like to participate if we get the chance. Certainly like to know what mines chucking out anyway, compared to the same motor that hasn't had ceramic fibre tape wrapped around the silencer. I can tell the note is deeper but would like to discover wether it's actually quieter.

The frequency of the sound can also be measured, so we can end up with db on tickover @ 2 meters and say 10 meters at 'cross wind' position for take off, and the frequency for each motor which should produce some interesting data.

Take a spin up when we nex have the weather for it Dave.

I will of course also take the meter to the fly-in.

SW :D

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just talking about props does anyone know if three or four blades produce more thrust? there is a lot of mixed answers so i am seeking the accurate one if possible

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just talking about props does anyone know if three or four blades produce more thrust? there is a lot of mixed answers so i am seeking the accurate one if possible

Yes, for the same diameter and profile, a two blade gives less thrust than a three blade and so on. The gearing/reduction must be changed though.

A huge two blade is the most efficient, if you can cope with a big cage etc.

I'm not clever enough to prove it. So happy to be shot down...

Cheers

Paul

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Cant argue with bathboy, :D

An interesting tool I came across while tuning the pink thruster.. http://personal.osi.hu/fuzesisz/strc_eng/index.htm

It dont account for pusher props.(is there any difference?) And you have to divide the revs by to take account of the reduction gear..Ie 4-1

But you can play with the figures till your hearts content....

I found the temperature settings explain a lot in the vast change of thrust, between cold morning and warm evening flights.

A good tool for figuring out the best prop for the power output of your engine :D

Colin B (2) (RAF) :roll:

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