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Solar-powered aircraft flown for nearly three weeks without landing

eandt.theiet.org

121–130 of 220 posts

Re: Solar-powered aircraft flown for nearly three weeks without landing

#121
post #117

Earlier quoted context omitted.

I've always been kinda fascinated by this solar yacht concept. I wonder now with post-covid remote working options and starlink if you could actually make it work. I do wonder though if sailing the ship is basically a full-time job in itself (navigation channels? Docking at foreign countries? Getting food etc?).

I have a 38' steel sloop with 400w of solar + a wind generator on-board. I'm not a full-time liveaboard, but I have been on-board for the last couple of months and you can definitely make it work. Sailing is labor intensive, but not in the ways you imagine. Navigation, docking and provisioning are all straightforward. Where it can sometimes feel like a full-time job is maintenance. Everything on a boat wants to break…

I learned a few years ago about barnacles, which by virtue of being unaerodynamic and super heavy if you let them form huge colonies on the bottom of your ship, can decrease fuel efficiency severely. I saw how much work maintanence was, I said 'nope!' I guess a house is similar in some ways. Shingles don't last forever, pipes get corroded. The salty sea though, it's a bit more unkind to things, aye?

Re: Solar-powered aircraft flown for nearly three weeks without landing

#122
post #113

This is great and points to how solar in some cases already can facilitate continuous operation without the need for refueling of planes, boats, cars, you name it. Expect this to grow as battery and solar cell tech develops further. My favorites atm are the yachts that are capable of sailing just about anywhere in the world without a drop of fuel. The price is prohibitive, but considering that you might not need a ho…

You know, sailing catamarans are a thing, right? Wind is more consistent than sunshine.

Sure, I know sailing catamarans well (via Youtube vids mostly admittedly). But I switched drooling focus when these things started appearing- I suspect they will eventually displace many if not most other boat types (albeit not in my lifetime), possibly using hydrogen (not battery packs) as energy storage. Sunshine is not required if I understand it correctly. No wear and tear on the sails, not dependent on winds to go from point a to b, more like driving than sailing, except no pollution, no noise.

Re: Solar-powered aircraft flown for nearly three weeks without landing

#123
post #23

Probably/unfortunately not really a Starlink competitor, right? They don't specify the "cruising" altitude, but I assume it's ~10 kilometers at most, probably less? Airbus would need quite a few of these in order to build a global internet connectivity service then. Edit: https://en.wikipedia.org/wiki/Airbus_Zephyr says ~20 km. Starlink sats (will) operate at ~540-570 km: https://spaceflightnow.com/2021/04/29/spacex-…

You wouldn't need that many. The line of sight area has 300 km radius. There's even a precedent. https://en.wikipedia.org/wiki/Stratovision

Re: Solar-powered aircraft flown for nearly three weeks without landing

#124
post #34

This is great and points to how solar in some cases already can facilitate continuous operation without the need for refueling of planes, boats, cars, you name it. Expect this to grow as battery and solar cell tech develops further. My favorites atm are the yachts that are capable of sailing just about anywhere in the world without a drop of fuel. The price is prohibitive, but considering that you might not need a ho…

Why wouldn't you use the wind energy also? It's a lot of fun, readily available and a lot cheaper…

The second link of the parent comment describes a optional automatic parasail tug.

Re: Solar-powered aircraft flown for nearly three weeks without landing

#125
post #117

Earlier quoted context omitted.

I have a 38' steel sloop with 400w of solar + a wind generator on-board. I'm not a full-time liveaboard, but I have been on-board for the last couple of months and you can definitely make it work. Sailing is labor intensive, but not in the ways you imagine. Navigation, docking and provisioning are all straightforward. Where it can sometimes feel like a full-time job is maintenance. Everything on a boat wants to break…

I learned a few years ago about barnacles, which by virtue of being unaerodynamic and super heavy if you let them form huge colonies on the bottom of your ship, can decrease fuel efficiency severely. I saw how much work maintanence was, I said 'nope!' I guess a house is similar in some ways. Shingles don't last forever, pipes get corroded. The salty sea though, it's a bit more unkind to things, aye?

At least with a house the timeline is long and it's easy to hire someone to do it for you. Even galvanized pipes last 40-50 years without much problem, and newer pex pipes may last indefinitely. Roofs are 25+ years.

Re: Solar-powered aircraft flown for nearly three weeks without landing

#126

Earlier quoted context omitted.

> I thought starlink didnt work for mobile connections? It will not work either far away from the shore.

Again I have to believe this is only a temporary restriction.

SpaceX are launching satellites with ("frickin") lasers now. So, if you are in the middle of the ocean, your packets step between satellites on the same orbit, forward or back, until they get in range of a node. First actual use is for polar service.

On certain routes, packets will be artificially delayed so that high-speed traders can pay big bucks to get their packets through first, ahead of fiber. And, maybe pay even bigger bucks to prevent their competitors from getting their packets through as fast. Imagine tiered pricing, where each millisecond ahead of the rest of the pack is ten times the price.

So, for example, orbits inclined near 70 degrees pass near New York and London/Frankfurt. Packets going by satellite laser links can get there many milliseconds ahead of those poking along on subsea fiber. Somebody in London who finds out 10 ms before everyone else about a price change in New York gets to make a killing trading on the exclusive information.

Re: Solar-powered aircraft flown for nearly three weeks without landing

#127
“ It is a sustainable, solar-powered, ISR and network-extending solution that can provide vital future connectivity and earth observation to where it is needed”

This military-industrial style of English always sounds very odd and is ubiquitous with these companies. Is it because they’re selling to Military buyers?

Re: Solar-powered aircraft flown for nearly three weeks without landing

#128

Earlier quoted context omitted.

I learned a few years ago about barnacles, which by virtue of being unaerodynamic and super heavy if you let them form huge colonies on the bottom of your ship, can decrease fuel efficiency severely. I saw how much work maintanence was, I said 'nope!' I guess a house is similar in some ways. Shingles don't last forever, pipes get corroded. The salty sea though, it's a bit more unkind to things, aye?

At least with a house the timeline is long and it's easy to hire someone to do it for you. Even galvanized pipes last 40-50 years without much problem, and newer pex pipes may last indefinitely. Roofs are 25+ years.

Not soaking your house in salt water really helps with longevity I've found

Re: Solar-powered aircraft flown for nearly three weeks without landing

#129
post #126

Earlier quoted context omitted.

Again I have to believe this is only a temporary restriction.

SpaceX are launching satellites with ("frickin") lasers now. So, if you are in the middle of the ocean, your packets step between satellites on the same orbit, forward or back, until they get in range of a node. First actual use is for polar service. On certain routes, packets will be artificially delayed so that high-speed traders can pay big bucks to get their packets through first, ahead of fiber. And, maybe pay e…

There is a whole world there I do not know and don't really want to. What a strange world we live in.

Re: Solar-powered aircraft flown for nearly three weeks without landing

#130
post #90
post #74

Earlier quoted context omitted.

…cause a boat to tilt to the side… This is a net positive. The alternative is to roll back and forth with the waves. It’s much nicer with the sail up and ata bit of a heel. Also, just to throw this in, one of the world cruising sailing couples which wrote for the magazines switched to a diesel powered boat as they aged and found that they spent less of fuel than they had on new sails. Sails are consumables if you car…

The alternative is a catamaran. Your point on the diesels still stands. Properly designed cats are unsinkable and don't readily capsize, but not weathering a storm is worth every penny invested in diesels. Besides one needs them in marinas anyway.

Electrical engines are more and more becoming a thing, especially for sail boats, where they server more for harbor and anchoring than covering distances.
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