your ebike also needs much less amps than the OpenPPG.
Care to share some details as to which brand and model of 20700 you used ?
Sure, 40 cells sanyo ncr20700b (4250 mah). It is actually a speedbike but discharge rate is indeed, with less than 1C, much lower than openppg. I noticed that the new pack provides much more power when draining as the original pack already notacibly dropped power after 15 minutes. I guess battery tech also has improved in the 4 years that I used the original pack.
Airborne finally! First flight this morning went really well. This was my first flight on the openppg, first flight on a paramotor, first flight in electric aircraft. I had paramotor friend help out, I’ve also been paragliding for 8 years and have 2000 hrs in small aircraft as commercial pilot just FYI.
My wife took some footage on the ground here’s short clip. But will be recording with chase cam on next flights.
As for the battery it performed really well. I flew for 20 min doing few circuits. The bms was only thing that got warm, wondering if I should put computer fan on it. It was around 50-56°c the entire flight unless I go off of power and glide temp dropped to 40’s. The battery temps were just fine no warmer then 33°c. Oat was 15°c. Starting voltage was 57.7, I ended flight early as I lost connection with bms to phone for the battery stats but after landing checked voltage and it was at 49.9v. The battery screen lost connection only few min before landing and was indicating voltage of 47.7v at 155amps. So only thing I need to worry about is the bms temp, if it gets to 60° I have it so it will shut off power. Doing some calculations if I fly this battery to 35v I might get 60 min flight times.
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Nice. Good job on the landing. Couldn’t get the video link to work but found your Vimeo channel
we have the same brand of wing. Nova.
Is it the Ion?
I am still flying my first wing, the Nova Prion 3 - EN/LTF A rated.
Awesome! Yeah I really like nova wings. I fly ion 4.
One thing my wife noted is that the openppg is extremely loud. I’m flying this off an acreage beside neighbors so not ideal if I get up at 7am to go fly and wake them all up on weekends hmm. We definitely need to find quieter propellers. Most people think of electric as quiet machines…
@Pdwhite have you guys found or are you trying to find a solution for this? It sounds like we might need different standoffs for carbon props as they don’t stay in place with just the one shaft locking bolt.
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Another successful 2nd flight! Flew 24 min tonight, start voltage 57.7 end 47.4v. Didn’t want to piss off neighbors and fly any longer. Feeling more confident in the battery and system will push more and more every flight to see max endurance. This is in calm conditions no lift. Loving the openPPG System!! Will start logging stats on every flight to keep track and share.
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Congrats!
I remember how it feels when you fly that thing the first time. no vibrations, no idle running combustion engine on the ground… awesome.
My wife actually said the opposite, but she was not where I launched, but I flew over our house later.
The reason for this difference is actually very simple: my combustion engine that I have produces a much deeper sound, the openPPG has a much higher pitched sound.
when further away, the openPPG will feel quieter than a combustion engine - that’s because high pitched noises don’t travel that far (due to physics).
The problem with the loud, high pitched noise is actually due to the design of the openPPG.
A large propeller with a larger pitch can spin much much slower
than four small propellers with a smaller pitch/angle of attack
to produce the same amount of thrust.
Our small props 22x10 need to spin at a very high speed - and when that speed even is close to or even above the sound barrier, it is indeed very very loud.
only much larger props with higher angles of attack can solve the issue.
Hey Thanks! Yeah it’s quite a ride as you said, no vibrations or idle. I love just cutting throttle and soaring on low or no power. Looking forward to thermal flying with this. Although I have never flown a gas paramotor so I can’t really compare sounds, vibrations etc. But my wife says it’s very loud on the ground.
I realize larger prop is quieter or deeper sound and less annoying but there are advancements even in small props, if you look at the dji mavic, I had the first and now second version, and with the new swooped tips on the props it is way less noisy, also sounds different, not as winey. I’m certain that we can find a prop at least 30% quieter and different pitched vs these. We need to work directly with a company to come up with a solution, I haven’t been able to find any off the shelf props that will do what we need because they are all designed for either large single prop rc aircraft or large multi rotors with way too much pitch. We need a custom design for this system to get the most efficiency and quietest results. People tend to think electric is quiet, so it’s a shame it’s so loud and will definitely deter people from buying the openppg.
It would be great if @Pdwhite would chime in on the subject so we know if they are working on finding a solution or if it’s up to us to come up with something better.
I would love some advanced props with swooped tips that are quieter. As for saying it’s loud that’s all relative… the motors don’t add to the noise like ICE do. Yes it’s loud but you haven’t flown ICE so in comparison they are quiet. The higher pitch noise tends to be more annoying and that makes it seem louder too. You could get a single prop electric but then you would have torque to deal with.
I would love to experiment with different props but that can get quite pricey fast.
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Hey Paul, for sure I realize I can’t compare it to gas, but I have friend who flies gas and as you said it’s a lower pitch, not as annoying. That’s mainly what I’m getting at. I think the designers of openppg should really be focusing on this issue. This paramotor should have the most efficient props possible as well as swooped tips for sound dampening. They could offer two options, the wood ones or for few hundred extra the more efficient quieter longer lasting props. Even the article in cross country said how annoying the prop noise is. To me it’s the weakest link with openppg and should be top priority to have a prop designed specifically for our use. It sounds like I’m not alone in this thinking 
.
If we could find out where that factory is, maybe they can do the job,
Ya it’s sort of the nature of smaller props. Even though the sound decibel reading is about the same higher pitch is more annoying. I’m sure we could find/design some props that drop the sound down a bit. I’m always looking for options if you guys see anything you think would do the job. Designing one would be a bit of a pain.
Thanks Paul for response.
I’m going to try these electric multi rotor props in 22x10. 5 weeks for delivery. They have nicer profile with swooped tips.
Hey @dzubot,
I already have the ones from XOAR in 22x10!
No difference in noise!
I broke my props, and the XOAR ones were the only ones available for immediate delivery within Germany (3 days) so I decided to buy those instead of waiting for cheaper ones from China.
The shape isn’t much different than the original props, and so does the sound not make a difference.
Just to let you know.
here you can see them in my “prop repair” thread: Wooden prop repair - #3 by etienne
Thanks Etienne good to know just cancelled my order on them since no difference.
I guess only thing left to try is carbon fibre Xoar but there seems to be no way to attach them without having them spin free
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I really want to try something like this. But they would require a custom mount and they aren’t rated to handle the thrust we output. I love the idea of a winglet for both efficiency and sound.
The advantage with T-Motor is, that they not only make the motors, but also Props.
one option is to possibly buy both from them, and have something custom made for our needs.
But that would be up to @Pdwhite and @zjwhitehead to negotiate something with them.
I believe the amount of OpenPPGs that go through their hands with each batch, any manufacturer would be willing to make something custom.
Especially when props do get damaged, and people will buy more throughout the life time of the OpenPPG.
May as well be true for props only.
Unless we are like really 20 to 40 people or so, willing to buy a set of four props, we will not succeed in something custom made.
any chance, @Pdwhite and @zjwhitehead that you would be willing to approach either a only prop manufacturer, or even T-Motor, who make both?
It would be beneficial for future batches, and probably some of us owning earlier batches would love to upgrade to something more efficient and quite.
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Now those are interesting props!