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Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

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Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#121

Post by jthomaslm »

ok_dad wrote: post #87

So at the Nurburgring, when they have endurance races, they use aircraft as “satellites“ for sending data from cars, such as onboard video and telemetry. Most race tracks can just use regular signals but this track is huge and wraps around a mountain, so you’d need either thousands of repeaters or the aircraft they currently use. You guys should try and see if they could use your tech, it seems a perfect fit and migh…

Wow, very cool! I've watched plenty of races at the Nurburgring but never stopped to think about how I was receiving the video feeds! If you have any contacts there I'd love to speak to them.

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#122

Post by pierrekin »

crabbone wrote: post #115
pierrekin wrote: post #104

Earlier quoted context omitted.

I am possibly wrong about small details, and would appreciate corrections. So when I joined the project, the physical aircraft was based in the USA, but the software team for the autopilot was based in the UK. For some reason - I think it was the very high altitude capability - the USA considered the autopilot to be munitions. When I first joined the project, there was this bizzare situation where it turned out to be…

Re' sending an entire aircraft over the ocean vs. sending software over the internet: you'd be surprised, but it's still often the case. I worked for a storage company that made a long-distance replication product (i.e. a program that allows one to store their data both locally and far away in a reasonable time-frame). We were contacted at some point by a movie production company which had this problem of moving the…

In my home country, there was a stunt where a person used a carrier pidgeon with a usb drive to race a local ISP transferring a file.

It got me thinking about strange units. Like how for example a car's mileage can be thought of as a surface area (distance per volume), or in this case how for every pidgeon speed, drive capacity and length there is an equivalent bandwidth capacity * (distance / (distance / time)).

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#125

Post by cyrieln »

mNovak wrote: post #72

How much power and weight budget will you have for payloads? I work with a startup that's developing tech for very low power consumption RF beamforming; I think HALE applications seems like a natural fit. Feel free to DM if you want to chat.

Sounds awesome! Would love to chat, email in bio.

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#126

Post by jthomaslm »

loxias wrote: post #81

This is GREAT! I've been interested in this space for a long time, and a friend started a UAV company. I've got nothing much to say other than it feels GREAT to see someone else doing a project I've always wanted to do but likely never would have gotten around to, and doing it well. Now I don't feel a "responsibility" to do it. ;-) Do feel free to hit me up if you ever need programming or DSP help ;-) I'm curious: wh…

Love the enthusiasm - it's definitely a very fun project to be working on!

Discussed a few of your questions elsewhere in the comments, but here are some thoughts on scaling laws:

Over-simplifying a bit for the sake of brevity: In general, for larger aircraft structural mass scales up more quickly than wing area (check out “indoor free flight models”). By using a span-loaded structure (i.e. having weight distributed along the wing span to match the way lift is spread over the wing) you can avoid some of these constraints and have an approximately constant structural mass fraction.

The aircraft is actually very quiet - it needs to be very aerodynamically efficient so it doesn't require much thrust. You can’t really hear it in flight, but I’m no audio engineer - so I don't know how useful microphones would be. Genuinely curious about this so if you have any pointers let me know!

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#127

Post by TedDoesntTalk »

flaghacker wrote: post #101
mannyv wrote: post #74

Power companies on the West Coast might be a great market for this. The downside is that the plane might have to operate in poor weather. Not sure if imaging can make it through the clouds etc. This might also be great for coastal/fisheries monitoring. Not sure how that would work exactly or who the customer would be. Definitely coast guards for the third world, who are resource-constrained when it comes to coastal p…

Interesting, what could power companies use this for? Checking for overgrown power lines? Checking for roofs to place solar panels one?

He’s probably referring to the wildfires started in California by power lines. There was a very damaging one in the last several years.

EDIT: here’s one link https://www.cbsnews.com/news/pge-55-million-dollars-old-powe...

Imagine dying because the power company didn’t update old power lines. What a waste of life.

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#128

Post by KaiserPro »

pierrekin wrote: post #104
pierrekin wrote: post #80

Earlier quoted context omitted.

I worked on this at Facebook very briefly. I believe the project was called Aquila internally. I worked with a famous engineer who joined Facebook from a well known british aircraft manufacturer. He was an aerodynamics expert and was trying to solve the problems of flutter and other dynamic instability in the extremely large, high aspect ratio, lightweight composite wing. I wasn't officially told this, but I believe…

I am possibly wrong about small details, and would appreciate corrections. So when I joined the project, the physical aircraft was based in the USA, but the software team for the autopilot was based in the UK. For some reason - I think it was the very high altitude capability - the USA considered the autopilot to be munitions. When I first joined the project, there was this bizzare situation where it turned out to be…

> the USA considered the autopilot to be munitions.

I could be wrong but it might be related to the GPS. Most off the shelf GPS units have a height and speed limit to stop them being used in ballistic missiles.

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#129

Post by ok_dad »

jthomaslm wrote: post #121
ok_dad wrote: post #87

So at the Nurburgring, when they have endurance races, they use aircraft as “satellites“ for sending data from cars, such as onboard video and telemetry. Most race tracks can just use regular signals but this track is huge and wraps around a mountain, so you’d need either thousands of repeaters or the aircraft they currently use. You guys should try and see if they could use your tech, it seems a perfect fit and migh…

Wow, very cool! I've watched plenty of races at the Nurburgring but never stopped to think about how I was receiving the video feeds! If you have any contacts there I'd love to speak to them.

No sorry, I’m just a fan of the Nurburgring!

“One ring to rule them all”

I would love to see solar tech replace polluting aircraft, though, since racing itself is likely to not be “green” in the near term.

Re: Launch HN: Radical (YC W23) – Autonomous high-altitude solar aircraft

#130

Post by cyrieln »

Leherenn wrote: post #105

How do you deal with temperature (roughly -60°C/-70°F)? Do you heat the batteries? What about icing? It might be too cold for it at that altitude?

Yes, the stratosphere has some tough environmental challenges like these low temperatures. To retain enough battery capacity, heating elements are required. The same is true for other onboard electronics.

Interestingly, because the stratosphere’s air is so thin, heat generated by the aircraft isn’t lost as fast to the surrounding air as at sea-level.

As mentioned by th0mas88, humidity is pretty low and icing typically doesn’t occur at these altitudes.

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