Mini thermal catchers - food for thoughts

[Voltair (Phil)]

The two Wasps weighed about 20lbs ready to go and the Bug (mine) 19.5lbs. True PG attachment points - no side canes/bars. They were great to thermal with. We could weigh-shift the way we paraglided.
I always wanted to have the same machine but electric.

Myself with a Wasp (sorry for the low res photos from the late 90’s:

I had shredded a windsock when I flew to close to it😆


Another prototype I designed at the time

This is the system I had designed to attach the motor, a Boxer engine.
The harness was custom made for me by SUPAIR and was based on an Acro model they had at the time. The motor was connected by 4 industrial velcro(s) and could be removed in 30 seconds from the harness, if you wanted to free-fly without the motor.

The takeoff technique was a bit different than what what standard PPG do. We had to recline a lot as soon as we could feel the thrust kicking in to bring the cage to a vertical angle and have a thrust parallel to the ground. It is kind of what standard PPG do but we had to lean back so much more. We had become used to it and was normal for us to run tilted so far back.
We were using small around 200cc Boxer engines.

I had all kinds of ideas at the time😄 and actually some people had the same ones years later and actually built PPG with cocoon harnesses.

I had posted this one before but here’s another lightweight proto I had built (under 20lbs without the SUPAIR PG harness. Note the dorsal reserve parachute with the orange handle to the right.

Sorry for the low video resolution. I actually flew with this proto Piccolo8PackTest2 iPhone - YouTube
Phil

[Bob27 (Austin)]

I have thought about building one of those with a DLE or 3W 170cc engine, but I never new that these where actually a thing.

[dannydanjal]

Hello I have made Mini 32" direct drive and I learnt to fly on that before I went on full size paramotor
Do you mind if I ask what make this 200cc boxer engine is, also does this work by firing both cylinder at same time or individually firing at every 180 degrees
I will share picture on my DLR170 once I find it

[NanoTrike (andres chapero)]

Why did all these amazing developements stop? These miniature paramotors were and are the future of sport aviation. Safe and cheap 15 minute pushers.

[bratwurst (Thomas)]

if the pilot is very light, you can fly safely with small systems. Yes that’s right. but as soon as the pilot weighs more than 75 kg you have to run the engine at full throttle in order to have a good climb. for this the motors, which are otherwise designed for rc models, need a lot of cooling air to last a long time. everything is possible if you want. you can also tune with race exhaust. but what always remains is an incredibly annoying sound and very high gasoline consumption. sometimes i still fly my dle 170 which has a specially tuned exhaust system and with auh with a pilot weight of 85 kilos brings it to a good height. but it’s just too loud and impractical for me. electro eppg for thermal has a thousand advantages.

the smaller the propeller with ppg or eppg, the worse the efficiency.

as an example (pilot 85 kilograms): with a 130 cm propeller you can fly around 800 meters high with 1.5 kilowatt hours of power or 1.5 liters of petrol. with an 85 cm propeller you can only cover about 400 meters with the same energy, gasoline or electricity.

the flight time is something like this. with 130 cm you can do 20 minutes. with 85 cm it is only 10 -12 minutes.

[NanoTrike (andres chapero)]

So the idea of a 10kg paramotor that will push a 85kg pilot for 15 minutes safely into the air is still decades away ? Lie to me… tell me it can be done today

[Bob27 (Austin)]

I don’t think the 10kg part is there yet, but a 14 or 15kg paramotor with say a 3w 275cc twin or maybe a 3w 342cc twin is totally possible for getting 85kg in the air.

[bratwurst (Thomas)]

yes the 275 he is a real monster. the thrust is enough. the decompression valves are very effective. but you need a reliable friend to start the engine on your back on the ground. a start in the air is impossible, not even with a retrofitted e-starter. there are rc model builders in germany who have already tried to retrofit it to e start for a large 35 kilogram rc-cessna. the engine has too much compression. a help would be to erode a deco hole afterwards, as the paramotors have in the exhaust duct.

[Voltair (Phil)]

Hi Danny,

Sorry, I will bombard you with photos from the past to show you what we could do with the Minis:

I actually flew the first prototype we made and it weighed 12lbs without the harness😆
The Boxer motors came from Poland and I honestly do not remember the brand.!
Sorry for the blurry picture.‘MiniNewTron2009|147x107
This photo shows a “standard” paramotor and my “BUG” next to it.

‘

Here’s a short with lousy resolution from the mid 90’s. - YouTube

We made three Minis and called them the APPS (Assisted Paragliding Propulsion System) , and used them many years. The three pilots respectively weights were (150lbs (me) flying the BUG , 160 and 170lbs for the WASP. The idea was never to launch from flat ground but cruise along to another thermal if we had lost the lift or catch ridge lift which I can do with the Paul’s X4.
I built many super light cages for my protos. Experimented a lot. It was fun to do.

With the net:

Building the jig for the assembly before the welding phase:

Another Mini I built fo4 paragliding:

Super light BUG bracket

The vertical bracket tubes were held in place via a zipping sleeve (one on each side) and a cover over it for a better look.

Sorry, in french, I had sketched various ideas - soft gas bladder - butt protector, etc…

My friend with his WASP (23lbs)

Soaring my bug (19lbs) for over an hour near sunset during the Summer (New Jersey). I was always punching the throttle and not letting go until I ran out of gas, then continued on thermals. Note the true paragliding connections - no side canes

My friend and his WASP launching - note the true PG connections as well. School training PG harness from SUPAIR

BUG warming up. I had a remote controlled gas throttle (no joke)

Taking off with the BUG

WASP

Thermaling with the BUG over a wheat field - again, no side canes/bars but true PG connections instead.

WASP THERMALING

WASP getting ready to launch

Here, you can see the real PG riser connections - no side canes because the motor was attached directly to the PG harness.

Nothing to do with PPG but here’s a winch I built with a gas Briggs and Straton motor to tow my students - it was loud, vibrating a lot and scared the cr.p out of me. I designed a few winches - now I use electric remote controlled ones.

My BUG:

From my view point with the BUG - WASP below.

[dannydanjal]

Hi Phil Thanks for sharing your experience Great work

You can check my first one I made with in Sup-Air harness/frame all in one piece on link below

Log into Facebook

For some reason many pics did not show but as broken file

What I am most interested in is boxer twin engines that each cylinder fires individually Your engine looks like it was the one that fires both cylinders same time by looking at single carburettor

What I was using Chinese DLE170cc

This was my test flight on DLE weight only 13KG including harness as you can see in Facebook link picked up by one hand

Feel free to ask any question or share any other topic of paramotor

Danny

[Voltair (Phil)]

Missing photos: perhaps it was because of the format. Some were .jpg and others .pic. Weird!
As for the Boxers they were firing at the same time. The vibration factor was low and the torque not an issue because of the way I rigged the motor onto the harness.
Before I came across Paul’s X4, this is what I had made for myself - The motor was from Germany

Phil

[Bob27 (Austin)]

The DLE170 also fires both cylinders at the same time. Here is a picture of the crankshaft to show you.

[dannydanjal]

Yes it is but not my favourite But then you use what is available

[Bob27 (Austin)]

Other than for ease of starting is there any reason why you would not want the cylinders firing at the same time?

[Voltair (Phil)]

They were firing at the same time, if I recall. It was such a long time ago. One carburetor system.

[dannydanjal]

To get the real benefit of twin engine is using smaller piston of half capacity compressing only half the volume at one time if the firing order is independent and spark happens every 180 degree like twice one cycle one cylinder produce power with other compress and cycle goes more smoothly unlike single cylinder power stroke send piston down from TDC to BDC much quicker than it goes up from BDC to TDC so there is non uniform cycle as every single cylinder and it makes no different if twin engine fires both cylinders together same thing happens as it is single cylinder engine
There are some twin boxers firing individually they are complex and expensive to produce because you need to have separate crank chambers and separate carb for each
I hope I made any sense

[Bob27 (Austin)]

All made sense. I just figured a typical 2 cylinder boxer would be better as it’s far more simple and you have next to no vibration (granted they would have more twisting vibration along the axis of the crank shaft at low throttle.)

[dannydanjal]

Twisting vibration will be same as single because it is compressing full volume once and fire once every cycle
People only look at crank and say this will be perfect balance when you look at but all other single cylinder also have well balanced crank
Crank is not a cause of balance