paramotor component choices for very high altitude

[bootstrap]

I'm trying to converge on the best choices of paramotor and components for high altitude flying.  I have drawn some inferences, but they may be way off.  So I hope others with more experience will chime in with suggestions.

Situation.  The location is the Atacama Andes high desert (northern Chile, southeast Bolivia and thereabouts).  The lower portions of the valleys between mountains is typically 4000 to 4500 meters altitude (13,000 to 15,000 feet) and the mountaintops are typically 5000 to 6200 meters altitude (16,500 to 20,000 feet).  Fortunately the general topography is not crazy-rugged mountains with not a square millimeter of flat.  Instead, most of the mountains are dormant volcanoes or similar shape with moderate slopes tapering off in all directions, and tons of flat to gently rolling topography in the generously wide valleys between mountains.  That's a bit of a simplified description, but fairly accurate.  In other words, one could lose engine almost anywhere and easily glide downward to endless easy landing sites (albeit often many tens to hundreds of kilometers from the nearest human being).

While I certainly intend to enjoy flying around for fun and lots of exploration, I also have a real reason and application besides moving to and living in such a place.  This area is the best place on earth for astronomical observatories. 350 days per year of clear skies, super dry air, super dark skies (no cities, towns or lights), and smooth gentle non-turbulent airflow (which ruins images for telescopes).  For this reason, most of the best and largest telescopes in the world live down in this area.  But they are not located on the very best sites because... no roads to the tops.  While some of the mountaintops are fairly rugged, many have small to moderate areas that are fairly smooth.  While those relatively smooth areas on a few mountaintops are large enough for a tiny very short takeoff airplane, most are not.  Which is where paramotors enter the picture.  It should be easy to land foot-launch and/or wheeled paramotors on most candidate mountains.  To test sites out only requires relatively small telescopes and instrumentation that can be disassembled into components that only weight 10kg to 20kg each.  And so, initial site inspection requires just me and paramotor (plus oxygen tank + mask) and detailed site testing of the best 3 to 5 sites only requires a few trips with 10kg to 20kg to deposit test equipment to perform detailed sky testing.  Finally, the goal is not to find locations for billion ton telescopes (like the biggest ones located down in these parts), but to find locations to locate much smaller specialized telescopes and instrumentation that can be operated remotely (anywhere in the world) via wireless internet connection.  Here too, each disassembled component can weight only 20kg to 30kg or so (or whatever is practical to haul up to 5000 to 6200 meters with a paramotor.

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Sorry that took so long, but now you know the situation.  The following are my naive inferences and questions:

paramotor:  whatever brand and model has the best combination of high power engine and minimal weight.  i assume foot-launch to save weight?

engine:  prefer 4-stroke for better fuel economy & wide range of altitudes, but... weight may rule out 4-strokes.  so my wild guess is the tornado280?

propeller:  my guess is some combination of large diameter + 3~4 blades + maybe greater tilt-angle on the blades (can't remember correct term)?

wing:  I have no idea, and need help on this.  Obviously it needs to be optimal for very high altitude, heavy weight, and probably nothing else.

other:  for my safety i should carry a compressed oxygen tank + mask for ~5000+ meters?.  maybe feed oxygen into the engine ~5000+ meters too?

other:  pull starter so i can definitely start engine when stranded somewhere.  would you trust batteries & starters at 6200 meters?  i assume not.

other:  my guess is no clutch, but that's just a guess.  maybe easier to pull-start with a clutch?

Fortunately the latitude is quite modest (minus 18 to 23 degrees), so either though it will obviously get very cold up that high (!at night!), it won't be insanely cold as further south (middle and southern Chile and Argentina).  Nonetheless, if there is anything I need to know about operation in very cold conditions... or just sitting all night long on top of the mountain while operating the site test equipment... let me know.  Obviously when I need to start the engine again after all night being cold... it needs to start.  Actually, having said that, perhaps that's not even true.  Assuming I can jog down a fairly steep slope (that just keeps getting steeper the further I go), maybe it would be possible to glide all the way down to the valley if the engine would not start.  Is that plausible, or the most insane idea you've ever heard?

Just a final note.  Without paramotor, this kind of opportunity exist.  Which is fairly cool, huh?  It would be insanely and definitely prohibitively expensive to fly people and equipment to examine and test out a whole bunch of potential sites like these with high altitude helicopters (which I assume exist, but don't even know for sure).

If you want to see what this area and topography looks like, maximize your browser to fullscreen, browse to the following page, and scroll down.  And yes, the Milky Way in those photos of the ALMA radio telescopes near the bottom really does look roughly like that with your naked eye... yup, so bright you can even see colors.  http://www.maxreason.com/south/south.html .

I welcome any suggestions... especially from anyone who has already been crazy enough to fly to such altitudes.  Bet you weren't at ground level when you flew at 6000 meters altitude! 

 

Edited February 12, 2018 by bootstrap

[alan_k]

Very interesting project bootstrap. You really need to speak to Gilo at Parajet as he was one of the pilots on the Everest paramotor challenge.

Best of luck with it.

[xNateX]

Hi bootstrap.

I'm waiting on the eos 4 stroke motor that's supposed to be released this year. While trying to find out whether that motor would have electric start or not (I personally prefer it), I received an answer from someone in the inner circle that it starts so easily it isn't necessary, but if the company has any extra time and/or funds to spend on the development, that efi would be a better area. Whether it gets efi or not I do not know. Perhaps at some later date. But it is worth monitoring the situation. Anyways, that's the motor I'm waiting on. It might possibly be a good fit for your situation also.

Good times to be living in. Old Rockefeller Senior with his $200 billion or so in today's currency couldn't do what we do regularly, not for any amount of money. Toss in so many other wonderful things (scuba diving, snowboarding, high mountain exploration where you're at) that this certainly is an incredible time to be living in.

Good luck in your endeavors and god speed!

[Mark Morgan]

Highest power out put would be the 250.. our Mac fly is 32kg so to my knowledge the lightest 250 on the market unless you stick a 250 in a miniplane or AC but there is not much in it. I get better fuel eco out of the 250 than i did from my 4 stroke..  Max power would be from the E props plug and fly 4 blade... 

[bootstrap]

Thanks for the feedback.

I will search for the "Everest Paramotor Challenge" and see what I can learn.

Yes, I've been waiting to see what comes of that engine on the Scout Paramotors.  I suspect that engine will be much lower power than the AirConception Tornado280 engine, but other advatages might make up that drawback... not that the existing Scout engines are wimps (they're not).

When you say "the 250" do you mean the Polini Thor 250 engine?

Polini Thor 250 == 36 HP @ 7500 RPM, 25kg weight, 85kg thrust (90kg with 3-blade prop) --- 2-stroke.
AC Nitro 200 == 26 HP @ 8100 RPM, 12kg weight, 72kg thrust --- 2-stroke.
AC Tornado 280 == 36 HP @ ???? RPM, 13kg weight, ??kg thrust --- 2-stroke.
Vittorazi Moster 185 == 25 HP @ 7800 RPM, 14kg weight, 75kg thrust --- 2-stroke.
Scout EOS 250 == ~25 HP @ ???? RPM, ~15kg weight, ??kg thrust --- 4-stroke.
Blackhawk Intruder 250 == ~35 HP @ ???? RPM, ~18kg weight, ??kg thrust --- 4-stroke.
AIE 225CS-40BHP = ~40 HP @ ???? RPM, ~10kg weight (possibly plus starter & muffler weights?), ??kg thrust --- 4-stroke wankel rotary.

The above is what I know about at the moment... actually, more like "what I think I know".

On the surface the AirConception Tornado 280 looks best (high power, low weight)... but is 2-stroke so who knows how it works at 20,000 feet altitude?

 

Edited February 12, 2018 by bootstrap

[paulg18]

Blackhawk make a 250cc four stroke with fuel injection, 35 hp and 18 kg called the Intruder. I have never heard any reviews on it so cannot comment on how good it really is. 

 

[bootstrap]

Thanks paulg18.  I'll add that to the above list by editing my post.

One more possibility (which I also added above).  If anyone knows much about rotary engines, please comment on the following:

http://www.aieuk.com/225cs-40bhp-wankel-rotary-engine ::: 225cc : 40HP : 10kg weight : liquid cooled : thrust == ??kg --- 4-stroke wankel rotary
http://www.aieuk.com/video ::: short video of above on test rig and some commentary

The full specifications are not available on the website.  I wrote to them via email and they require an NDA to get additional details... which I might do after I get opinions from here.  However, their email did provide me a couple other factoids, including a very high unit price (quantity == 1):  16,500 British Pounds EWX == $23,000 USD "including ancillaries" (though I don't know what EWX means).  I assume "including ancillaries" means "including starter, radiator exhaust pipe, muffler, air filter and housing, water, oil, and any other components needed to be a complete working system).  While that price is rather insanely high, it might be worth considering for my application if everything else works out.  But also, I suspect these engines are only made in small quantities in their prototype shop, so the price might come down if they had sufficient orders.  Or maybe they can sell them for such a high price because their main customer is probably the military-industrial-war-complex to power some of their drone airplanes that they kill innocent people with.  For those people, price is close to no object.  Nonetheless, I'd hope for a lower price in quantity.

Thanks for your help.

PS:  They quote torque at 27 lb/ft @ 8000 RPM... and show a nice flat torque versus RPM chart on that web-page (25~27 lb/ft from 5000 to 8000 RPM).  Does anyone know what trust that will produce with the largest 3-blade or 4-blade eprop (or similar from another propeller supplier)?

PS:  I also don't know how to interpret their "fuel economy" measure (0.54lb/bhp/hr).  Can anyone here compare this strange measure with any existing paramotor engines?  Does 0.54lb mean like 0.54 pounds of gasoline?  I hope that doesn't mean 2 liters per BHP per hour!  If we assume cruise (not climb) is only 10 BHP, that would translate into 20 liters per hour of cruise.  Does that sound high to you guys?  Sounds high to me, but I don't know.  If climbing at maximum power, that would work out to 80 liters per hour.  Yikes!  20 gallons per hour?  That's 150 pounds of fuel per hour!  Hopefully I calculate this radically wrong!  I am almost certain that somewhere it said fuel consumption is roughly the same as conventional 4-stroke internal combustion engines!  Maybe someone here can explain that measure.

Edited February 12, 2018 by bootstrap

[Ivan]

Good evening.

I have been to Chile precisely to the part of the country you are talking about and I have been flying at up to 17 000ft as well (not in Chile).

My main concern is that you are considering foot launch. At the altitude of 4000m. the density of the air will be quite low in comparison to the sea level and you may need to run with a speed beyond your physical ability...  Therefore I would personaly consider trike. 

With the engines for the trike there is a variety of choice from Rotax (but weight is there) to Polini 250 and others. I definitely would not be in favour of going after anything rarely used.

Polini should do the job I reckon. Ideally you will need the prop with adjustable pitch angle.

The wing choice is quite a complex discussion. I would think about something semi-reflex having a bit better climb rate then specialized reflex wings for paramotoring.

Your fuel calculation is wrong indeed, do not be worry, you will not spend more than 8 - 9 liters per hour.

 

 

[bootstrap]

Thanks for your comments Ivan.  My decision to default to foot-launch is largely to minimize weight.  Here is how I think about this issue:

CASE A:  Explore for fun and photos:
  - The only payload besides pilot is fuel and camera.
  - Can always find modest to moderate steep hills to run down to make takeoff easier.
  - Can stand or sit on seat in back of pickup and have assistant drive [into breeze] to speed required to take off.
    - Do you know if others have taken off this way before?

CASE B:  Circle and land on candidate mountaintops:
  - The only payload besides pilot is fuel and camera.
  - Can always find modest to moderate steep hills to run down to make takeoff easier.
  - Can stand or sit on seat in back of pickup and have assistant drive [into breeze] to speed required to take off.
  - Need to land on mountaintops, and some may be fine for foot landing but too rocky, rough or irregular for trike wheels to roll in a stable manner.

CASE C:  Haul test equipment to mountaintops:
  - The payload includes pilot, fuel, plus moderately heavy equipment (perhaps up to 50kg or more).
  - Can sit on equipment sled in back of pickup and have assistant drive [into breeze] to speed required to take off.
  - Presumably the equipment is mounted to a detachable "sled" mounted beneath the pilot and attached to paramotor frame.
    - Presumably the pilot "pulls a pin" when the sled is 1 foot or less above ground to make the sled falls off and slide to a rather quick stop.
  - Presumably the pilot would then fly a wide 360 turn and land next to the sled on foot.

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Other issues:

Landing Speed:  Your point that the required speed to land (and not stall first) at 6000 meters altitude may be faster than I can run... is a good one.  Here is the way I was planning to deal with that issue.  Before I land the first time on any given mountaintop I will drop [a tiny weather station device and] windsock next to what looks like the best landing spot.  After that I will always know the exact wind direction & velocity via wireless communication from the weather station device, plus the same information less precisely from the windsock.  Therefore, I can circle around and know exactly which way to land directly into the wind.  Whenever the wind velocity is much below the safe landing speed of the paramotor, I just won't land that approach, or that day.  If I want to land with heavy payload, then I will require an even higher smooth wind speed.

Foot Launch:  Why not fly a 4-wheel paramotor?  First, that's a lot of extra bulk, weight and cumbersomeness to drag around for no reason in cases A and B above.  Second, that would probably rule out some potentially good sites because they lack any large enough area that is also flat enough and smooth enough for wheels.  In a manner of speaking, I plan to design and build a framework that more-or-less converts a foot-launch paramotor into a 4-wheel paramotor... except without the 4 wheels.  Actually, I suppose I could design it so the "equipment sled" has 4 detachable wheels.  Then I could actually land the sucker like a 4-wheel paramotor... on those sites that have a smooth enough area of sufficient size on top.  I suppose this whole topic is worth thinking further about, but I really do hate the idea of paying for two whole paramotor systems... or always hauling around that big bulky 4-wheel blob wherever I go... with my apologies to everyone who prefers to fly on wheels.  Hey, every airplane I've ever flown has wheels... and I wouldn't want it any other way!  Hahaha.

Oh, perhaps the other issue is takeoff speed when time comes to leave a 6000 meter altitude mountaintop!  Hahaha.  Yup.  Well, I guess my answer is... being that I'm on a mountaintop... which drops off in every direction... hopefully being able to run [steep] downhill makes me appear more athletic!  Hahaha.  Needless to say, this is a case where aborted takeoffs might not be a very good option (or even possible in some cases), so definitely only start when the breeze is nice and smooth, and the wing is in perfect position & completely stable.

[bootstrap]

Oh, Ivan!  Since you flew to 17,000 feet, you must be able to give me advice about choosing the right wing.  I've been reading, reading, reading and trying to draw inferences from all I read, but... experience can't be beat.

From my reading, my best guess so far is the Ozone Spyder.  I also heard the latest Ozone Viper is super efficient, which might help, but I also get the impression it might be too "active", for lack of a better term.  I also assume I'd want a fairly big size, since I'll be hauling a lot of weight up to 20,000 feet once I choose the best site I can find.

Of course I welcome input on this question from anyone.  Thanks!