[HN Gopher] Solar-powered aircraft flown for nearly three weeks ... ___________________________________________________________________ Solar-powered aircraft flown for nearly three weeks without landing Author : OJFord Score : 233 points Date : 2021-10-11 15:49 UTC (7 hours ago) (HTM) web link (eandt.theiet.org) (TXT) w3m dump (eandt.theiet.org) | hellohntoday wrote: | I'm assuming the flights were achieved mid summer when they days | are longest and it can't yet operate outside this window. | | If this is the case, shame they don't just admit this up front | phnofive wrote: | Perhaps they are aware of eatrh's axis and will move operations | to the southern hemisphere? Or adjust the drone's speed to stay | in sunlight? | Arrath wrote: | > Or adjust the drone's speed to stay in sunlight? | | Depending on altitude, that would require an awfully fast | aircraft. | Johnny555 wrote: | They ran the 18 day flight test in September, so not the dead | of winter, but also not on the longest summer days: | | _A solar-powered aircraft has completed an 18-day test flight | offering hope it could be used to create internet access for | billions of unconnected people around the world...The test | flight touched down in Arizona on September 13._ | | https://www.thenationalnews.com/world/the-americas/2021/10/1... | | Phoenix has about 12.5 hours of daylight on Sept 13th. | (compared to ~14.5 hours on June 21st, ~10 hours on Dec 21st. | GhostVII wrote: | What's the benefit over something like a weather balloon? | | Pretty interesting thought, tape a few hundred micro SD cards to | it and you've got some impressive bandwidth. | brandmeyer wrote: | Google's Titan project was going to deliver internet service | (... _before it got strangled in the womb grumble grumble_ | ...). LTE from aircraft to client, and a dedicated point-to- | point radio from aircraft to backbone. | detritus wrote: | You can tell this where to go - weather balloons are utterly | beholden to the whim of wind patterns. | runarberg wrote: | I thought that you could somewhat control a balloon by using | different wind patterns in different elevations. | | https://www.youtube.com/watch?v=NvJ2Ei8K2DI | bentcorner wrote: | ?Por que no los dos? | | It looks like solar-powered zeppelins are a thing, although | with the brief googling I did it looks like nothing really | exists just yet. | GhostVII wrote: | Yea I guess I was more thinking of a kind of blimp, where it | still has some solar to allow it to maneuver around, but not | to actually stay up. | | If the aircraft needs to stay in one place maybe that would | be less efficient though, since it would be harder to fight | winds. | jcun4128 wrote: | The wing tips look wicked, not sure if necessary | laurent92 wrote: | Isn't taxi-takeoff-landing what consumes the most energy? It's | often 10% to 25% of the total flight consumption for supersonic | planes like the Concorde (but not for the SR-71, since they | refueled in-flight to fill the rest with inert gas | https://theaviationgeekclub.com/former-sr-71-driver-explains... | ), and still a lot for the other planes. | OJFord wrote: | Based on your percentages then, I think you mean most per unit | time? So then, given three weeks far exceeds normal flight time | (by more than 1/25%)... | elif wrote: | I like the optimism of the article but I can't help but believe | that the primary purchasers of this capability will be armies and | spies. | fredliu wrote: | Wasn't Facebook working on a similar project (Aquila)? | wanderingstan wrote: | Yes, it was cancelled in 2018: | https://techcrunch.com/2018/06/26/facebook-permanently-groun... | akozak wrote: | Doesn't appear to have a payload in the picture. That would add | weight & power draw. | nabla9 wrote: | First communications satellites were just passive reflectors. | They were just big inflated balloons made with reflective | material. | | Same idea could work with solar powered aircraft. | | https://en.wikipedia.org/wiki/PAGEOS | | https://en.wikipedia.org/wiki/Project_Echo | not-my-account wrote: | "Airbus ultimately believes that the aircraft could remain | airborne for "months at a time" and could provide internet to | both commercial and military customers." | | What sort of power requirements would this bring? I assume that | it would be more sophisticated than just dumping RF energy | indiscriminately across a huge area. | zarazas wrote: | But there is starlink for internet in rural areas | onychomys wrote: | Sure, but even if these planes managed to somehow cost as much | as a starlink satellite, it'd still be cheaper to do it this | way because having some dude toss it up into the air for | takeoff is basically free compared to even a fully reusable | Starship flight. | kbenson wrote: | They're hoping to get six months flight eventually out of a | propeller craft. I can't help but wonder what we could eventually | get out of a solid state craft.[1] They mention batteries in this | article when referencing that six months target, but I have to | assume servicing the propellers is important as well. | | 1: https://www.engineering.com/story/how-the-worlds-first- | solid... | Asmod4n wrote: | You got a small typo there. | kbenson wrote: | Lol, thanks. :) | bagels wrote: | To fly through the night, you need energy. I'm wondering if it's | more efficient to store it in the batteries, or as stored kinetic | energy by flying to a high altitude and descending through the | night. | teraflop wrote: | It's a good idea, in principle. But according to the sources I | could find, to get enough gravitational potential energy to | equal the electrical capacity of Zephyr's batteries, you'd have | to lift the entire craft by about 70km. | | https://www.aviationpros.com/engines-components/aircraft-air... | | https://en.wikipedia.org/wiki/Airbus_Zephyr | | I can imagine you'd want to take advantage of gravity to a | certain extent, but it seems a bit tricky to estimate how much. | Presumably there's a particular altitude at which the | aircraft's overall efficiency is at a maximum. Deviating from | this altitude allows you to store a bit of extra energy (which | means you can get away with a smaller battery) but you don't | want to deviate too far, or you'll lose more energy to various | inefficiencies than you're saving. And you probably need to | keep some electrical reserve power anyway, in order to be able | to actively navigate away from unfavorable winds. | kbenson wrote: | There's also the fact that this is optimizing for power usage | in the air, when really what we'll want to optimize for most | likely is power usage while _doing some specific task_ in the | air, and that task may necessitate specifics of what | altitudes it can function at. | Ph0X wrote: | Assuming you didn't care about the path, could you also take | some optimal path where you go east to west to prolong the | days, then go west to east to shorten the nights. Could | probably play with south/north too depending on the time of the | year to get longer days. Or maybe you can go far enough to the | pole where it's always day. | gusgordon wrote: | For those curious about the physics of these aircraft, here's an | analysis I did of the same concept. The goal is to determine the | smallest aircraft configuration that can indefinitely sustain | flight: https://github.com/gusgordon/atmospheric_satellite#readme | onychomys wrote: | Is there a reason you optimized the amount of starting energy | in the battery? I know basically nothing about how solar power | works, but surely you'd just fill the battery up to 100% with | an extension cord on the ground before launching it? | mkr-hn wrote: | Batteries are heavier when fully charged. Takeoff weight | matters. It's not much heavier, but it might be enough to | affect things at this scale. | | edit: remember the context. This is about an abstract | optimization to find the minimum viable aircraft. | rrss wrote: | what kind of batteries are meaningfully heavier when | charged? are you just talking about like E/c^2? | luma wrote: | Gas tanks :D | jermaustin1 wrote: | A water/gravity battery comes to mind. Definitely not the | answer you are looking for, but an answer none the less. | enchiridion wrote: | Depends on your definitions. Is the water pumped | considered part of the battery before it's elevated? | jermaustin1 wrote: | The pumping of the water would be "charging" the barrel | of water, I guess. | einpoklum wrote: | I'm sure this will work great for powering an aircraft, | too. You could just let it all hang from an anchor at the | highest point in the battery :-P | spijdar wrote: | I can't tell if this is satire or not, but taken in good | faith, how? | | A fully charged battery would necessarily have more mass | than a fully depleted battery, but the difference should be | so tiny as to be immeasurable. Or am I wrong? We're | essentially talking about the sum weight of a bunch of | electrons, which are extremely light. There's no other | exchange of matter going on when charging/discharging a | battery, just the creation/destruction of chemical bonds, | and associated movement of electrons. | btilly wrote: | A battery doesn't have a static charge. When it | discharges, electrons move from one side to the other, | then back through the batter, and you modify which atoms | have which elections. But it continues to have no static | charge. | | However it has less potential energy. And therefore you | change mass by the mass associated with that potential | energy. | [deleted] | luma wrote: | I can't tell if you're being serious. You are _technically_ | correct, but also incredibly wrong in suggesting that the | increased weight would be substantial enough to impact | anything measurable. Depending on the size and capacity of | the cell, you might see a difference due to general | relativity on the order of nanograms. | | see: | https://physics.stackexchange.com/questions/34421/does- | the-m... | p1mrx wrote: | A nanogram saved is a nanogram earned. | gusgordon wrote: | Good question. One requirement for the aircraft in this | optimization is that they must have more energy in the | battery than they did 24 hours prior. If the aircraft started | at full energy, they wouldn't ever be able to satisfy this | requirement, so that's why it's an independent variable. | | For example, an aircraft could "start" at 50% battery state | of charge, then charge to 95% over the course of the day, | then come back 24 hours later at 51%, and that would be | valid. There are other ways around this, but this is what I | came up with at the time. | | This is similar to why the starting altitude is allowed to | float. The gravitational potential energy of the aircraft can | be used as another "battery", but the aircraft is only a | valid solution if it's not losing altitude over the course of | 24 hours. | jcims wrote: | Maybe it helps surface how much charge is required to climb | to altitude vs how much charge is required to sustain it? | This may also help surface how much of a buffer you may have | in takeoff time in order to survive night. E.g. if you | require 100% charge then it's likely you have to take off at | a fairly specific time of day. | algo_trader wrote: | nice analysis | | Is it feasible to operate these at lower altitudes? | | e.g. can we have solar/air drones posted every 100 miles of | interstate highway?! | gusgordon wrote: | Yes it's a lot easier at lower altitudes since you can get | more lift, but you might run into some extra regulatory | issues with that :) | giantg2 wrote: | I would love a low cost electric ultralight. | jack_riminton wrote: | " 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? | marcodiego wrote: | Complete outsider doubt: Does this has the potential to replace | satellites? Or, why did google project loon failed? | elif wrote: | A craft like this is more likely to serve | predator/reaper/sentinel missions. Particularly ones in | locations you don't want the aesthetics of full state | surveilance but still want the same operational capacity. | Tade0 wrote: | Not mentioned in the article, but the li-ion batteries onboard | the aircraft have a silicon nanowire anode thus achieving amazing | energy density: | | https://www.amprius.com/2019/10/airbus-partners-with-amprius... | stavros wrote: | Do you know what sort of density and discharge rates they're | talking? | tehjoker wrote: | I wonder how the engine can keep operating for such long periods | of time without maintenance! | endymi0n wrote: | This stuff is pretty sturdy. The lifetime of brushless electric | motors used in this kind of dirtless environment is basically | the lifetime of the bearing used and can usually be measured in | years of nonstop operation without any modification already. | JCM9 wrote: | In 1958 two guys flew a Cessna 172 nonstop for 64 days without | landing. They refueled mid-air via a truck that drove under them | during a low pass. | hodgesrm wrote: | Good Lord, what an adventure! Thank you for posting!! I had no | idea about this flight. | | Here's an account that popped up on Google. | | https://www.aopa.org/news-and-media/all-news/2008/march/01/e... | markl42 wrote: | how did they um...."defuel" their bodies and such in the air? | philk10 wrote: | https://news.ycombinator.com/item?id=18158207 | spookthesunset wrote: | Summary: they pooped into plastic bags and tossed them | overboard. | orzig wrote: | Even more impressive, they did it before audiobooks! | njovin wrote: | I had never heard of this record until now. Cross-country | flying in small planes like this can be incredibly tedious and | the refueling sounds very dangerous. I can't imagine doing it | for this long. Apparently, neither can the guy who did it: | | > When asked by a reporter if he would ever replicate the | stunt, Cook replied: "Next time I feel in the mood to fly | endurance, I'm going to lock myself in a garbage can with the | vacuum cleaner running, and have Bob serve me T-bone steaks | chopped up in a thermos bottle. That is, until my psychiatrist | opens for business in the morning." | | Source: https://www.airspacemag.com/daily-planet/airborne- | for-64-day... | sokoloff wrote: | Related (in at least one dimension): | https://www.airspacemag.com/daily-planet/airborne-for-64-day... | | Cessna 172 flown for 64 days, 22 hours, 19 minutes and 5 seconds. | etaioinshrdlu wrote: | The linked article on that page is broken. I'm guessing he | somehow refueled in flight? | sokoloff wrote: | Yes. Also added oil. | ceejayoz wrote: | Yes. They flew low and slow over a long, straight road and | refueled from a truck that kept pace with them. | | https://www.aopa.org/news-and-media/all- | news/2008/march/pilo... | | > A Ford truck, donated by Cashman Auto in Las Vegas, was | outfitted with a fuel pump, tank, and other paraphernalia | required to support the aircraft in flight. When fuel was | required, a rendezvous would be arranged on a stretch of | straight road in the desert near Blythe, California. An | electric winch lowered a hook, the fuel pump hose was picked | up, and Timm or Cook inserted it into the belly tank. It took | a little more than three minutes to fill the belly tank. | | > The total fuel capacity of the airplane was 142 gallons. | Plans called for refueling twice daily. Sometimes weather or | the inevitable glitches upset the schedule, and a new | rendezvous was worked out by radio. This activity was | repeated more than 128 times. | | The whole article is worth a read; it was quite the hairy | sounding endeavour. Two months in a C-172 would kill me, I'm | quite certain. | belthesar wrote: | https://web.archive.org/web/20120429214314/http://www.airspa. | .. | | Haven't read it to find the answer to your question yet, but | bless the Internet Archive | sologoub wrote: | > When asked by a reporter if he would ever replicate the | stunt, Cook replied: "Next time I feel in the mood to fly | endurance, I'm going to lock myself in a garbage can with the | vacuum cleaner running, and have Bob serve me T-bone steaks | chopped up in a thermos bottle. That is, until my psychiatrist | opens for business in the morning." | | ROLF!!! | mr337 wrote: | I think he sums this up nicely. What a feat! | mistrial9 wrote: | https://en.wikipedia.org/wiki/Cessna_172 : | | "From December 4, 1958, to February 7, 1959, Robert Timm and | John Cook set the world record for (refueled) flight endurance | in a used Cessna 172, registration number N9172B. They took off | from McCarran Airfield in Las Vegas, Nevada, and landed back at | McCarran Airfield after 64 days, 22 hours, 19 minutes and 5 | seconds in flight. The flight was part of a fund-raising effort | for the Damon Runyon Cancer Fund.[14][15]" | j245 wrote: | Neat - but not interesting from a technological stand point. | andrepew wrote: | Over 1500 hours of continuous operation is quite a feat. | Components like magnetos have service schedules much shorter | than that. | | This also ignores all the unexpected issues that pop up in | aviation. My only experience with Cessna 172s are rentals | which are treated like crap - those planes need something | looked at like every 50 hours. | OJFord wrote: | Is it not? I don't imagine such sustained flight, continuous | operation of all the equipment and engine for so long, | would've been a design consideration. | | Presumably there's a number, I just doubt it's tens of days, | so isn't it _interesting_ that it was achieved? | j245 wrote: | This record was set ~3 months after someone else did it for | 50 days. | | From an engineering stand point, performance of components | or materials are always assumed to be much worse than | actual and the forces / conditions they are subject to | overestimated, with further factors of safety applied on | top. This is how it should be. It also means properly | designed things will carry on working better than you | expect (on average). | | It's not interesting (to me) from a technological stand | point compared to the solar UAV because flying up and down | the same road with a truck refuelling you is not useful, | and if others (e.g. Military, NASA) could be bothered to do | it - they would probably do a better job relatively easily. | | To me - It's the same as building the worlds longest domino | trail. You could beat the previous record by 1 million | dominos which is neat but.. what have you proven, and why | does it matter ? | OJFord wrote: | > This record was set ~3 months after someone else did it | for 50 days. | | Fair enough, I didn't know about that, I'd have been _as_ | interested to hear about either of them first, and like | you not so much the other second. (And I doubt the | commenter that shared it meant it as 'wow look 64 | compared to 50' either.) | cornellwright wrote: | You can see the aircraft used at the Las Vegas airport. It says | "Hacienda Hotel" on the side and I think it's hanging over | baggage claim. | tpmx wrote: | 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-launches-60-mor... | rlt wrote: | They would have the advantage of variable density based on | demand, i.e. more of them over population centers and none over | oceans, whereas LEO satellite constellations are pretty | uniformly distributed because they're orbiting. | | It's sort of in between a stationary cell tower and LEO | satellite constellation. | | But then you have to worry about them failing and hitting those | population centers, whereas satellites deorbit slowly and | usually burn up completely. | Ottolay wrote: | The U2 operated at over 20km, so maybe the altitude is higher. | | I suspect the greater issue is vehicle cost, lifetime, and | safety. A starlink satellite is much smaller (and as result | cheaper) and is rumored to have a 5+ year lifetime. Also, at | end of life it burns up in the atmosphere. No worry about | pushing the life on a component and having it crash and kill | someone as a result. | elif wrote: | Glide based efficiency crafts absolutely need thick | atmosphere. They don't have supersonic jets. | Ottolay wrote: | The U2 was subsonic. Also, un-powered gliders can get up to | impressive altitudes. | | https://www.airbus.com/newsroom/press- | releases/en/2018/09/ai... | JackFr wrote: | > The unmanned glider, which is powered by two small | propellers, | | I'm confused by the article and the above comment. Isn't | a glider by definition unpowered? | runarberg wrote: | I'm a bit puzzled by the economy here. Is creating, lunching | and orbiting a satellite really cheaper then flying an | airplane? Is it really cheaper to have a decommissioned | satellite totally burn up in the atmosphere then reusing | parts of an airplane to fix another, recycle unusable parts | and put the rest in a landfill? | | The economics here just seem wrong. | ethbr0 wrote: | USD2021$15M per Falcon 9 launch (re-used, assuming first | launch was paid for by a customer) [0] | | 60 Starlink satellites per Falcon 9 launch [1] | | = + USD2021$250,000 in launch costs per satellite (+ | manufacturing / ops costs) | | [0] https://www.elonx.net/how-much-does-it-cost-to-launch- | a-reus... | | [1] https://space4peace.org/starlink-gears-up-to-launch- | nearly-1... | Ottolay wrote: | As a reference a new Cessna 172 is $432,000 [1] and that | is not a high tech aircraft. | | [1] https://www.forbes.com/sites/erictegler/2021/04/28/pr | ices-fo... | runarberg wrote: | This feels like comparing potatoes and pineapples. | | A _new_ Cessna vs a _used_ Falcon 9 _launch_ hardly seems | like a fair comparison. The cost of the rocket is written | off as externalized. The actual satellites are not | factored in at all. Really what we are comparing here is | the cost of an operation vs the cost of an airplane. The | economics still seem dubious. | rlt wrote: | On top of this, if Starship is successful ("fully and | rapidly reusable") it could bring the launch cost down | another order of magnitude. | | And because Starlink is building thousands of satellites | it has economies of scale that no previous | satellite/spacecraft had. | tomxor wrote: | [EDIT] remove redundant info | | > Airbus would need quite a few of these in order to build a | global internet connectivity service then. | | Yes it would require more units, but with a much smaller cost | per unit for build, launch and maintenance. That's where it | will start to get interesting: Which will have the lowest cost | per GB, per user, per square km of coverage etc? | | I suspect even if it's cheaper it would still remain less | global, since having massive swarms of these would probably be | even more of a logistical nightmare than starlink. i.e they | would supplement other technology... which is pretty much what | Airbus is quoted suggesting in the article. | Gravityloss wrote: | 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 | Tepix wrote: | These planes can compete with Starlink in certain scenarios, | for example you can launch them in the event of floods that | knock out the regular telecommunications infrastructure. | tpmx wrote: | With Starlink soon having ~global coverage, why bother | transporting, launching and servicing these aircraft for a | one time thing? I don't see the benefit. Will also be really | hard to reach low prices for end user terminals with this | approach. | | Very high quality visual/signals surveillance seems like a | much more obvious market fit. | btilly wrote: | First, Starlink has limited bandwidth per square mile. | Therefore it cannot conceivably provide telecommunications | for densely populated areas. | | Second, all you have to do is make these aircraft | compatible with cell phones. So your target population | already has "end user terminals" literally in hand. | | Third, this is not a one-time need. Local disasters happen | fairly regularly, and sometimes can be predicted in | advance. (For example hurricanes.) There is real value to | an instant telecommunications network that can be deployed | on short notice. | | Now I don't claim that this is actually economically | viable. But it is not exactly crazy, either. | tpmx wrote: | Pretty good points. Starlink can't do 2G/3G/4G/5G with | mobile phones on the ground, ~550+ km away, of course. | | They should probably look into partnering with e.g. | Ericsson Response (https://www.ericsson.com/en/about- | us/sustainability-and-corp...). | kbenson wrote: | > Very high quality visual/signals surveillance seems like | a much more obvious market fit. | | Oh, yeah, there are already companies the provide complete | surveillance of cities or large areas of cities so that | even if a crime scene is discovered hours or days later, | they can just go back to that time and track vehicle | movement to and from the crime scene to wherever it ends up | as long as it's in the same (large) area. | | Reducing the cost of the equipment that does the recording | of the area will only make it more accessible to more | police departments, for better or worse. | stareatgoats wrote: | 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 house | anymore it is actually getting close to possible for a reasonably | senior tech employee. | | [full disclosure: no affiliation] | | https://www.azura-marine.com/aquanima-45/ | | https://www.silent-yachts.com/silent60/ | mattlondon wrote: | 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?). | zdragnar wrote: | I thought starlink didnt work for mobile connections? I.e. | that it had to be registered and operated at a fixed address. | | That said, unless you are able to drop anchors, I am guessing | that you would spend most of your working hours at a dock or | with a partner piloting instead. | noitpmeder wrote: | I believe this is only temporary and SpaceX has announced | plans to roll out different subscription plans (including | roaming) in the future. | baybal2 wrote: | > I thought starlink didnt work for mobile connections? | | It will not work either far away from the shore. | noitpmeder wrote: | Again I have to believe this is only a temporary | restriction. | ncmncm wrote: | 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. | dragonsky67 wrote: | There is a whole world there I do not know and don't | really want to. What a strange world we live in. | Stevvo wrote: | 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 all the | time. Doesn't matter if the vessel is brand new or 40 years | old; finding a balance between maintenance and life is | difficult. | goldenkey wrote: | 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? | rootusrootus wrote: | 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. | llbeansandrice wrote: | Not soaking your house in salt water really helps with | longevity I've found | Tepix wrote: | Why wouldn't you use the wind energy also? It's a lot of fun, | readily available and a lot cheaper... | oefnak wrote: | The second link of the parent comment describes a optional | automatic parasail tug. | jjcm wrote: | From the images on the site it looks like it deploys a | sailing kite in addition to the solar powered engines. | KineticLensman wrote: | Oh hi jjcim. Another cool research project from where I | used to work. [0] Back in the day, the development building | had a great view of the runway during the Farnborough air | show and my pals on the Zephyr project would give me a | shout if anything interesting was taking off. | | [0] https://en.wikipedia.org/wiki/Airbus_Zephyr | Retric wrote: | Sails have several major downsides, most notably they take up | a lot of deck space and cause a boat to tilt to the side. If | you're regularly sailing long distances it's much faster but | top speed isn't that big of a deal when your living on the | boat full time. | | Other options like kites and wind turbines can work well but | they all all significant upfront costs as well as ongoing | maintenance issues. Spending that same money on a bigger boat | gets you much more space, and of course a generator can give | you redundancy or higher top speeds. | jws wrote: | _...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 care about performance. | silisili wrote: | Interesting last point...curious why is that? Do they get | battered from weather and physically tear, or do they | just stretch/thin over time? | lstodd wrote: | 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. | _ph_ wrote: | Electrical engines are more and more becoming a thing, | especially for sail boats, where they server more for | harbor and anchoring than covering distances. | Fiahil wrote: | > Sails have several major downsides[..] | | Yes, but it makes less noise. | Jeff_Brown wrote: | Also less disturbing to the ecosystem below than a prop. | pbhjpbhj wrote: | >top speed isn't that big of a deal when your living on the | boat full time.// | | If you're living on your boat 365 then I imagine avoiding | severe weather becomes more important? | bumbada wrote: | This is the reason Weather reports and forecast are so | important for people on boats. | | Most people living in boats actually live on ports and | don't get very far from the coast most of the time. | Stevvo wrote: | You know, sailing catamarans are a thing, right? | | Wind is more consistent than sunshine. | stareatgoats wrote: | 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. | rektide wrote: | anyone else think it would be super damn fun building solar | floating homes like this? | pcardoso wrote: | A local company does this, but they are intended to be mostly | stationary. | | https://www.waterlilyboats.com | mariusseufzer wrote: | I'd be down haha - When do we start? | agustif wrote: | If sea levels keep rising a lot of coasting could be like | this. | | In the netherlands they have flaoting houses in the canals, | but stationary AFAIK | bserge wrote: | There's a couple living on a cheap ass floating tent/home | (it literally uses barrels to float) in Sweden I think. | Pretty cool. Also narrow boats in England are cheap and | rather nice. Could start there. | | https://youtu.be/jljkK9HMa44 | pjc50 wrote: | You definitely want to try an English narrowboat before you | start. I know people that have done this; it's romantic, | but at its least romantic you're living in a not very well | insulated damp trailer. | notahacker wrote: | I'm on board mine now! I guess the theoretical benefit of | the seagoing version is your roof space isn't constrained | by the size of English locks so you might actually be | able to fit enough solar to power the vessel. That and | find good weather... | kwertyoowiyop wrote: | It's so depressing to read that one proposed mission for this | plane is...monitoring oil spills. | pvarangot wrote: | I worked on a satellite imaging startup. For this kind of stuff | usually oil and gas and large scale agriculture are the first | ones to show interest. They don't need great resolution or | revisit times and their assets span over very big areas so | monitoring from the ground/sea or with small drones is really | expensive. | esel2k wrote: | Depends on the appplication. An NDVI analysis or determining | vast crop / growth problems yes but if you want to check for | disease this is often done by drones to have higher | resolution. I could imagine doing regular field visits with | these planes and avoid the high labor costs of drone | management/flying. | | Sources: I work in a big agtech company with satellite | imagery. PS: We should connect. | pythonaut_16 wrote: | Why is that depressing? Unless you have some silver bullet to | remove the need for oil or prevent any future oil spills it | seems like creating innovative technologies to detect them as | soon as possible is a good thing. | | It would be like if someone developed a cheap, non-invasive | technology that could detect cancer extremely early, and then | you complained because they hadn't cured cancer instead. ___________________________________________________________________ (page generated 2021-10-11 23:00 UTC)