Right from Scratch DIY

Finally found a solution:

With canopy it looks way different:

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@Bodewah

Becouse there is no cutawaysystem

And freefallingsequence with motor and equipment seems to be no good idea.

Iā€™m talking about bailing out, not cutting away. Again observing the first rule of flying: Always plan for the worst case. If I were to fly over water Iā€™d rather not use a paraglider. A trike with a good rigid wing is best for reliability sake.

  1. A simple bucket seat with a single point seatbelt release could be used to make it easier to bail out. Iā€™d use a static line for this. Bailing out would take seconds and deployment would be almost instantaneous.

  2. Rigid wings are far less susceptible to collapsing in turbulent conditions.

  3. The payload can be increased with a trike allowing for there to be way more batteries.

It would not be easy to prepare to fly over water but done properly I think itā€™s much safer than flying a small single engine aircraft over the same 20 mile stretch. Wired properly the unit could potentially fly on just 3 of the 4 motors in the event one went out.

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@ bodewah

Understand your ideas,

Just thought in any violent much g rotating situation it could be challanging to bail out without cutaway handleā€¦

I had the opinion that to throw a reserve in a way that it does not collide with the other stuff allone would be inough stress, but if you would manage to bail out in a save hight and get away far as possible from all other equipment would be a good joice.

And not be trained in skydiving people dont like to bail out or cutaway from any m2 of canopy, even with static line.

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love the audio selection on Gift wrapped tumbling. first song ā€œdo you really want to live for ever, forever youngā€ acro to slo mo fallā€¦ second song after reserve deploysā€¦ ā€œim bullet proof nothing to looseā€¦ I am titaniumā€

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@fredrick 00

Solution refuel in flight

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Haha, so epicā€¦ I was gonna post this in here today! :wink:
I was thinking you could totally do that with a battery packā€¦ but itā€™s a lot heavier, so I might want to actually hook it with a beaner on a short rope so my footā€™s only guiding it. Youā€™d probably need to gain altitude, then hook up the second battery, then flip the switch from one battery bank to the other, then you could come back and drop off the depleted battery pack (or fly with it, and you could flip the battery switch back to drain the last of itā€™s juice as needed)
Maybe thatā€™s the future of LiPo paraglidingā€¦ launch w/ 5 minutes of battery life, pick up another 2 hours/100lbs of batteries once youā€™re already in the air :wink:

Iā€™m a sailor and a dive instructor, and getting sucked under water by wrapped lines attached to your PPG or EPPG would be pretty terrifying, and quite dangerous. Iā€™ve had anchor lines go taught as the boat reaches the end of the line, and gotten dragged off by a high tension kink, and other similar situationsā€¦ anyone without training or extensive water experience/comfort would definitely wrap themselves up in the lines and drown if they start wrapped in lines, and arenā€™t free if they donā€™t have flotationā€¦ anyone with training would have a chance of a narrow escape. (Main reason training matters is staying calm and dealing with issues in an order that helpsā€¦ like free your straps before trying to swim awayā€¦ Iā€™ve had divers get a straight taught fishing line snagged on their tank, then proceed to roll it around themselves until they were trussed up and helpless) A high G entry where you couldnā€™t untangle yourself before hitting the water would be particularly devastating. (whip-lash, air knocked out of lungs, dazed, head possibly shoved back to hit something hardā€¦) If itā€™s just a power out landing, however, you could unstrap before hitting the water, and then the trick will be to keep your canopy from overshooting you when you land so that it doesnā€™t end up infront/across you dragging you down. If you get gift-wrapped in the water attached to a sinking motor, thatā€™d be itā€¦ but if youā€™re over water, you should really have flotation.
The concern about electric shock and fire is overrated, I believe. If the batteries burn up, theyā€™re still back there in the water, so the fire wouldnā€™t spread, and the flotation is in the front. (So the pilots not underwater) The batteries (in salt water) would short instantly which could create a very high volt/amp discharge, but would be fairly short followed by a minimal leaching discharge. In the ocean, that current will travel every direction, and your body would be no more grounded than anything else, so it wouldnā€™t be a focused jolt like if you touched a negative and positive wire.
Different people also have different resistances to electricity. (The more resistance you have, the more dangerous it is for you :wink: I, for example, have touched 110 numerous times, and 220, all while barefoot, the 220 while on a ladder, and I only ever experience a tingling effect. (Tinging on to numbing if I maintain contact) Iā€™m pretty quick about breaking the connection, and donā€™t tempt fateā€¦ but so far, in over half a dozen encounters with 110, itā€™s only mildly alarming for me. (Apply it closer to my heart or spine for a party though :wink:
I would be really interested to see some tests where they toss a high A/V LiPo pack into salt water, and measure the currentā€¦
If you water sealed your battery and the contacts (which it already is right?), and then wired that to a fuse before it feeds anything else, then a short would only occur momentarily, and would be virtually no risk to anyone. The builds which are used probably have that or an identical mechanism built in already I would imagine.

@frederick 00
Did you see the 3 videos from the link waterlanding what would happen?

I think you are right electric shock is not the problem but burning with a lot of toxic smoke when you are trying to breath to live is not ideal, also the filmed reactions of the damaged lithiumnatteries under water are very violent, if a very small battery can selfignight to a glassmelting fire in the wather i think big ones like the bonkas used here are not less dangerous if damaged and under water.

Yeahā€¦ pretty fun stuff! :wink: Hopefully if you have to do a water landing itā€™s because of something manageable like a motor outā€¦ if you have to do a water landing gift wrapped, then the dangers are pretty notable w/ or without motorā€¦ hopefully you land conscious and donā€™t die on impact!
The smoke would suck, but youā€™d either be above water breathing (which is good at that point), or the smokeā€™s the least of your worries. Coughing right before you get sucked under again would be regrettableā€¦ but if youā€™re not getting sucked under, hopefully you can untangle yourself and get free of the smoke. From the videos I found on lithium hazards, fire, and salt water discharge, the smoke/steam did not seem to even be a minor irritant on the small scale batteries they usedā€¦ makes me think itā€™s not a bad enough toxin that it would be much worse than any rubber fire or the like. (Short term anyway.) Good news is, the wind will probably take your canopy down-wind of you turning your paramotor so the smoke is also down-windā€¦ once you get free enough that your not right over it. Iā€™m curious as to which lithium fire video you watched / are referring to? Were they able to create a fire without severely sabotaging the battery packaging first?
WRT fire, Iā€™m looking at the openPPG, and the batteries are mounted a bit closer to your back than I had envisionedā€¦ but, they are on the other side of a good deal of fabric and frameā€¦ the frame should slow down the time it takes any fabric to catch, particularly in the water, and the water would help disperse the heat. I probably wouldnā€™t volunteer to be gift wrapped to that, but if youā€™re not strapped in, it wouldnā€™t be hard to create some spaceā€¦ and, the fire will only happen if the actual battery components are exposed to the water, or if a short manages to not burn the wire up firstā€¦ a fuse would eliminate the second risk, and well sealed batteries would notably reduce the first.
Iā€™d love to do some salt water crash tests to see how it all pans out, but probably out of the budget to do more than 1 accidentally :wink: $500 to throw a battery pack in salt water is probably more than Iā€™m willing to spend unless Iā€™m actually planning a water crossing with them. (By the time I plan to do a water crossing, I expect dual carbon batteries will be the new norm which will eliminate many of the safety hazards mentioned)ā€¦ but they do use LiPo in boats and subs with minimal protections in place, and Iā€™m not familiar with horror stories from that.

@ fredrick 00 [quote=ā€œfredrick00, post:50, topic:207ā€]
Were they able to create a fire without severely sabotaging the battery packaging first?
[/quote]

No

Here you see how batteries are build

Only if they get too hot at charge or discarge or if they have an internal short (which is also a fast discharge) they can catch fire.

As you see in the video of the factory or the waterexperiment the lithium layer is on a thin sheet.

As the batteries need cooling you can only protect them with a ventilated housing.

If you check the celltemperatur and watch out to not let them overheat nothing should ever happen as long as there is no shortage in the system or a mechanical damage at the pack.

If you would land at a resevecanoppy on a hard surface you could eventual damage a battery.

The soft packs are not used for rc buggies becouse there are always shocks and vibrations.

Solution could be a cutaway for the batteries which also have to disconnect the cables from the system and let go all batteries away.
maybe 2 stage release of the pack - first drop to 7 meter webbing hanging under you for safe landing as the military troopers use for landing theyr heavy gear under a canopy and 2. Stage if necessery releae coplete via handle or just cut the webbing and drop it comlete.

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Pretty sweet video, though it felt way longer than it was for some reason. When they layer the lithium on the aluminium, then roll it, I expect it removes the lithium surface area / opportunity for oxidization which creates the explosive reaction you see when exposed directly to water. They smash them between sheets of aluminium, then wrap it in aluminium and vacuum seal it. All of that will keep the chemical reaction from raging uninhibited.
When I was first searching for salt water LiPo, I was expecting to find some sort of freak accident. What I found instead was the proper ā€œsafeā€ disposal method for a LiPo battery. Youā€™re definitely not supposed to have it strapped to your back when you do it, and with as many cells as a paraglider is going to have, it would be more dramatic than represented in the videos I watchedā€¦ but you can still see that the process isnā€™t incredibly dramatic. If you spaced the batteries 1" off of the mounting plate, it would give enough space to reduce the heat damage and penetration of the backing plate to a manageable level I expectā€¦ particularly if you have a layer of heat resistant foam or other material as your back rest.

I agree redundant electrical motors sound more reliable than a single engine plane. I would want to have a whole second electrical system as well possiblyā€¦ you could have them separated by a (1 2 both off) electrical switch similar to how RV or boats manage battery banks. Then you could use all your power, while also having redundant power systems.
Even if you lost two motors, you should be able to max thrust your two remaining motors, and maintain altitude for quite a while. The efficiency at max speed is less overall, and youā€™d have to let it cool, but fixed wings tend to be pretty aerodynamic anyway, so if you allowed for the possibility, I think it might work out.