 Hello, whoa, hello. I got your attention. Right, great. Cool, well, we're eight minutes behind schedule, so as I start my next two minutes, we should be fine. You can't see any of these slides, I guess, so I'm going to do my absolute best to narrate them amusingly. Some of them hopefully have video which will have loud, bassy sounds, so you'll be able to hear that and just imagine the rest of it. Right, cool. So, hi everyone, thank you for coming to this talk. I'm broadly talking about high altitude balloons. There's this really beautiful photo on the screen that we took from one of our high altitude balloons. It's about 35 kilometres above the surface of the Earth and you can see this curvature, it's really pretty. There's the gentle transition from the Earth, this thick blue atmosphere out to the black of space and by the edge of a photo it's just black in that space. And this is this classic photo that we get on most of our flights and you really can't see any of it. So, just close your eyes and dream of NASA satellite photos of Earth and you'll get the gist. Okay, great. So, outline of this talk for some handy bullet points. I'm going to start off with some stuff that isn't high altitude ballooning but is fast exciting rockets that are almost as high altitude because that gets the best videos. And then dig into the high altitude ballooning itself. There's a brief overview, what is high altitude ballooning and why do we do it and how does it work. And then a little bit of chat about the electronics we build and these payload systems we've made. Some talk about the software systems. We've got this really great community where lots of people can get involved and feel like they're actively participating while sitting at home in their hand radio shack. So, that's exciting. Then a kind of history trip through some exciting launches we've had in the past and more recently and my guesses at the future. I actually gave this talk two years ago at the last EMF and had this great slide of things that might happen in the next two years and they all happened so I've got some new ideas this time and we'll see how that goes. And then some quick details on how you can get involved yourself and finally details of how high altitude balloon launch we'll be doing at EMF hopefully. Okay, this is the slide with a photo of me and some details. I'm Adam Gregg. I'm an engineering student and for the last few years I've been a member of Cambridge University Space Flight which is a student society. We do high altitude balloons and rockets and other things that kind of excite us. And I'm also nominally a member of something called the UK High Altitude Society which is a very loose collective of people who are interested in these ballooning stuff and kind of come together to work on, I don't know, interesting balloon stuff. Yeah. Okay, on with the videos. Don't know if this is going to play or what because I exported it from PowerPoint in the car on the way here. Give me a sec. There's no sound and you can't see the video so just skip right past this. Never mind. High altitude ballooning. Okay, there's another beautiful photo. You can just see the outline of the airfare but you probably can't. On to the overview. High altitude balloons, these really big balloons, they're really made of latex, some people have been experimenting with different materials more recently and they're actually manufactured for meteorological radio sonde balloons. These are the things the Met Office launches twice a day from ten places across the country and they go up and they pop and they come down and the Met Office looks at where they went on the way up to work out where the winds are blowing and therefore predicts the weather. We fill them with helium or sometimes hydrogen which is more flammable but cheaper and attach our own payloads to them and usually the payloads are doing a similar kind of thing to these Met Office balloons. They have a GPS unit on them and most GPSs will work just fine at that kind of altitude. They get their position and relay it down over a radio and there are a few options for the radio system. I'll talk about those in a bit. Then on the ground you receive where your payload is hopefully figure out where it's going to come down and go pick it up and maybe you've put some cameras on the payload to get your beautiful photos. It's really the high altitude ballooning thing in a nutshell. A lot of people are into it because they like the photos. Some people like making the custom electronics. There's a lot of scope for doing interesting, exciting things on the electronics. Then the things are coming down off the radio. Someone's got to receive these signals. Usually you receive the radio signals yourself but because the protocol is open anyone across the country or across the world can pick them up if they've got a good radio and an antenna. We've built this whole system where anyone who wants to can download the software, listen to these balloons and report back on where they are. There's some great slides with photos of that too. This is where having my speaker notes on the screen would have been fantastic. I guess I'll talk about the electronics first. A classic kind of payload is an Arduino, a GPS unit that spits GPS data out over a serial. If you've ever used a GPS you know exactly what that looks like. Formats the message, slightly sends it back over the radio. Radio modules vary. You can buy a thing off a shelf but you stick into your Arduino and it needs nothing else. You just chat to it by toggling the pin high and low and your job is done. All the way through to building the radio entirely yourself from scratch with PLLs since a huge FAF and it does not work the first time. On the screen are some pretty photos of various electronics people have made. The radio telemetry, for people who know about radio we use usually something called RTTY which is where you have these two frequencies that's kind of frequency modulation and use it to send binary data. So if you have one frequency that's a zero and the other frequency that's a one and you just send out serial data. If it sounds kind of primitive it is. It predates pretty much every other form of technology. This is the stuff people used to have with the actual mechanical teletype printers over the radio. But it works well enough for us. How well is well enough? So these payloads are transmitting with 10 milliwatts of power which is about as much as your car key fob to unlock your car. The balloons are something like 30 kilometres up and say 500 kilometres away from you and we still get telemetry just great. So it's like 5 or 600 kilometres distance. Same power as your car key fob and you pick up this telemetry. The secret is it's really, really slow. It's like 50 board data. So you're staring there and you can see that each character come in slower than you could type it. It's awful. On the screen now is a map of a system we've built. I can see it kind of. There's a map of the UK and you can see these little radio masks where everyone who's running the software we've written has shown where they are and they're picking up signals from these balloons. Yeah. Cool. Let's move on to the more interesting parts because you really can't see much of these slides. We launched a cuddly dinosaur into space. It was a photo of a cuddly dinosaur in space. We launched from teddy bears into space. This was quite good fun. We went to a local primary school. Had a big outreach event. Got two different classes of kids to build spacesuits for their teddy bears so they could keep them warm up in space. The kids got to learn about insulation and building stuff and they got to be a bit crafty. They stuck some names on the teddy bears, some little flags. They look really sweet, right? I don't know. Can anyone see anything on the screen? I mean... Great. I'm loath to touch it. It's kind of big and heavy. Anyway, there are these teddy bears and we put firmest couples temperature sensors deep inside the teddy bears and sent them all up into space. The kids are all excited, waiting to see how warm the teddy bears stay. At ground they're maybe 12, 13 degrees C a healthy body temperature for teddy bear. By the time they got into space they were just 40. So they didn't survive that trip. But it's okay. The kids learnt a lot. There's a photo of some really rusty electronics now. Often you don't get these things back. Especially in the early days of a hobby back when people didn't really know what they were doing and we had much less sophisticated tools for predicting where the bloom would go. It was kind of a potluck. You launch your thing and it comes down somewhere and you really hope for the best. It's somewhere easy to get to. And we thought that was the end of it. Till four months later it's washed up on the coast somewhere covered in rust. Someone's found it walking their dog on the beach. Gave us a phone call. Pulled the SD card out. Everything was beautiful. Still got the photos. No trouble. Yeah. Cool. More exciting than just sending up cameras and getting photos. One of the projects Cambridge University Space Flight did was a collaboration with the European Space Agency. So if you're a space agency and you're looking to land things on Mars which you do because Mars is great you need parachutes for the very, very scary couple of minutes between orbit and on the ground. And if your parachutes don't work you will be on the ground in more pieces than one and you'll have a sad day. So you need to do these parachutes right. The problem is in Mars the atmosphere is really thin. You're de-orbiting so you're going to be supersonic. Supersonic parachutes are a whole load of black magic. If you want to test your parachutes in the right conditions you even need a huge wind tunnel of which there is one in the world and it is very expensive. Or you try and be a bit cleverer which is what we tried to do here. So the theory is Marsian atmosphere is quite thin and Earth atmosphere is quite thin at 20km altitude. So you take your parachute up to 25km or so and release it. Let it fall down until it's hit its terminal velocity which in this case is supersonic and then really, really hope the parachute deploys because otherwise whoever is underneath is 12kg supersonic lump of fiberglass and metal is going to have such a bad day. This will go straight through an engine block. So like the level of very, very careful planning you go to to make sure this thing has like it splits into three parts. Each part has two different parachutes. Each parachute has two different pieces of electronics which can fire the parachute. So we're really, really sure the parachutes will work. So yeah we take this thing up to 25km let it go. It accelerates until it's going really fast. Parachute comes out. We collect loads of great data. The European Space Agency gives us tons of money. Everyone is very happy. There's some pretty diagrams we made on how it would work but you can't see them. There's a great video where we paid someone to take this up in a helicopter to test it at a low-ish altitude just to make sure the parachute is deployed but you don't have sound or video. So if you imagine a helicopter kind of hovering I don't know 100m above ground and suddenly there's quite large orange fiberglass contraption. It looks a lot like a missile quite bulky but it's pointing down which is the wrong way. Suddenly it drops. It starts falling. There's an intake of breath from whoever's holding the camera. Beautiful parachute unfolds and someone goes Yes! Then it hits the ground gently. So that's that video. There are some still photos of it that you also... Can you maybe see a kind of missile-shaped orange blur? Yeah this is it under the parachute. It's great. Okay and then we eventually did the real test in space and it was a great video with this parachute being deployed in space. Cool. Never mind. We sent an android phone into space so a lot of people have been playing with easier electronics. If you don't really feel like programming your own thing or soldering up an Arduino for apps or you can write an app for your phone. Phones have a GPS phones have cameras, phones even have their own radios built in so it can just text you where it is. It works quite well. That was fun. More recently people have been doing some more exciting things. Traditionally we sent positions back down over the radio and you had to go and find your payload and really hope it survived and so forth to get the photos off a memory card. So obviously why not send the photos down over the radio. Sounds great but at 300 board it's still several minutes for a tiny, tiny thumbnail. People have been working on this slowly and we're now at the point where you get kind of good images. There's like I don't know I should take this to the glitch art tent really because this is all the photos of space corrupted by radio noise. It's another beautiful photo of the earth's atmosphere and the gentle curvature of the earth against the backdrop of space. This one transmitted live from one of these high altitude balloons. And then finally the other really obvious thing to talk about in terms of exciting hub flights. Sometime between last EMF and this EMF someone called Leo Bodner decided oh this looks like a fun hobby and in the last I don't know year has launched something like 70 balloons. So he's refined this payload thing down to a fine art. I mean 70 is a lot of these balloons. You probably can't see it here but it looks like a really cool tiny satellite. It's got little solar panels. It's about the size of a stick of gum. It weighs 11 grams and it goes up on a balloon. His very first flight kind of launched from wherever he lives and came down a few miles away and it was by all accounts fairly pedestrian. The next flight drifted out into the North Sea which is not uncommon. The next flight hit France which happens on a very rare day maybe people started to pay attention. The next flight went even further into the North Sea. We're now up to flight 10 and it's drifted over France into Germany down past Lithuania almost hit Ukraine and landed in Turkey which is a bit more exciting. He continued flying, launching a couple every day for a long while. This one goes into Germany up past I don't know parts of Scandinavia and ends up landing in Ukraine. The next one goes even further past Finland and lands in Russia. We're up to flight number 40 and it's gone past the Arctic Circle. Flight 44 lands in Syria. 45 and you're really starting to see what he's going for here. Drifts all the way past North Africa and ends up landing at the corner of this map but maybe you can see South of Russia past Afghanistan. Flight 47 and last heard from just over Japan. At this point no one really knows where it landed but it probably had a sad time in the sea. Flight 52 and we've done a big circle all around Southern Europe past Turkey and back again into Ukraine. At which point people are starting to think what is his secret and it turns out the secret in this case is trying 52 times. It works great. It turns out you can get this thing down to a fine art. These payloads are every bit as perfect and precise as they need to be. They weigh as little as possible. The solar panels mean they can run for as long as they need to go on. The balloons start getting more and more special. Now we're on to flight. Oh, well yeah. There's been a thing running for a few years where people are like what would be really great really really great is if you could get a balloon all the way across the Atlantic Ocean because it's a really long distance and transatlantic has always been this big thing in aviation. Everyone's always wanted to go transatlantic and for a long time people would try and they'd come up with such fantastically complicated systems. You had these balloons with loads of mechanical contraptions and valves and satellite modems and all sorts and they kept not working and it kept being very upsetting. Really difficult from the UK because the jet stream always blows you east instead of west. So you pretty much have to launch from America or get really lucky. That was the status quo until some group in California launched a bog-standard balloon and by freak chance it went all the way into Mediterranean and everyone was like well let's forget about that. Everyone was kind of hoping maybe one of these balloons would float across the Atlantic and eventually one did the long way. So in fact this balloon was launched when all the way out over Russia, over Alaska all across continental America then did the transatlantic before finally coming back to where it was launched from and has since done the same thing again so it's now circumnavigated the globe twice. Did so over like 30 days and obviously he's not going to stand still and not launch anything for 30 days so a day after this one goes up another one is launched and it's done the same thing one circumnavigation is great but what would be really fun is skipping directly across the north pole so in fact comes within 10km of a north pole going straight up and down the other side of the earth and there's a top down view that you probably can't really make out but it is in fact going all the way around which is great and then there was a third one of course and the third one has also gone round the earth twice so he's kind of blown all the records out of the water these things are still in the air they're still transmitting maybe one will drift over EMF while we're here in any event they keep going round when they come over you can pick them up and listen to them and they drift on their merry way I think it's like 35-40 days of continuous flight now which is crazy and there's no end in sight so those have been some very exciting launches there's another map of all of them so last time I said what might happen, what are people going to do in the future what are interesting directions to go in and there were things like maybe people should start using these radios for stuff like actual photos and people have done that which is great and there was this idea of these Pico launches where instead of taking a huge latex balloon you take a very small kind of foil balloon or plastic balloon and people have been doing loads of that in fact all of these long duration floats have been these special balloons he makes them by hand now they're made out of the same plastic that you get in microwave food containers long duration floats and then finally I was like maybe someone will finally do the transatlantic and that's happened so exciting things to play with in the future now especially if you wanted to get into things and kind of push the boundary a little through these new radios the Laura radios which have built in error correction they're actually really fast they'll probably work a lot better than everything we've used so far plus they're about £5 on eBay which is a quarter of the price that's an expensive amateur rig to receive them so probably that will become really popular TurboHab which is mapped in the corner over here invented same radios as before but with actual error correction and it's kind of nice and binary and efficient and if you're an engineer it kind of pleases you because the old format was about as inefficient as you could get if you tried and the new format is about as efficient as you can get if you tried on the other side of the spectrum probably all heard of Raspberry Pi which is this small cheap computer Pi in the sky is a thing that sticks on to it and turns it into a hab payload so now all you need to do is buy the thing and stick it on and you have a computer on a balloon and you can do clever things with that computer maybe and then finally there's this new networking idea coming about which we're playing with a TMF in fact called UK Hasnet which is where we say instead of always people manually tuning radios and pointing them up balloons and trying to get data down wouldn't it be great if it was all automatic you have a thing in your garden and it can chat to other things all over your house and people nearby and if a balloon comes overhead it just chats to it automatically and they relay messages and maybe the balloon lets your house network connect with your friends house network on the other side of a country and all the while it's connected to the internet and everyone can see where all the balloons are and it's starting to happen and it looks like it will actually work and if those radios here at TMF someone elsewhere in England might be trying to launch a balloon to go over us and see if the whole talking to everything automatically will work which will be great great, so the getting involved slide if you too want your own pretty photos of earth but you can't see on this projector but I assure you are beautiful it's very easy to get involved there's a friendly UK high altitude society there's a great IRC channel called hash high altitude on three nodes there's a website which has everything you need to know and it's UKHS.org.uk and it's on the screen but you can't see it so yeah and there's a great wiki it's got loads of examples it's good fun more excitingly launching from EMF time is to be confirmed because I only arrived half an hour ago location is Haftville which I don't know where that is but it's straight to this tent right down the far corner apparently is it near A2 it's near A2 and so this time two years ago we did the same thing we had this 100g latex balloon we bought two of them at the time it's about this big and we attached a payload called Joey which was this fun little experimental thing we just made and we let go we duct taped it into a jiffy bag and we said if found please return because we figured we're not going to go out chasing it now and up it went and we all had some fun and we tracked it and then somehow the duct tape failed the payload fell out of a jiffy bag and hit something like 60 metres a second which is 150mph going down and then crash landed in central London so as successful flights go this wasn't the best we got a lot of really angry emails my favourite was the one calling out for me to be banned from all future uses of a distributed tracking system which I felt was a bit harsh given as I wrote half of it anyway we're doing exactly the same thing this time we've got a new batch of joeys none of them have been made since for catastrophe two years ago but I found the PCBs so we sold it up six more we've got the twin 100g balloon it's the same one as the two we bought two years ago and it's been kept in a bag ever since it's probably fine twice as much duct tape twice as much duct tape is pretty much for plan maybe we'll put a little power shoot on it but I don't know if we have any power shoots no no power shoots so twice as much duct tape there's one tool I should mention which is this predictor we have and it uses this high altitude wind data to predict where your balloon will go and it's great if you know some properties like it will burst at this altitude and you can avoid central London you can avoid airports you can avoid military bases you can avoid all these things we've hit in the past and had really awkward phone calls about and we used the predictor two years ago and it said it would be fine and then the balloon kept on going twice as high as we expected and hence central London so this time we don't know really it will probably be good fun so we'll probably put it on schedule we'll send out an email to the schedule people I suppose come along to a hab village if I'm going up it looks quite cool we'll track it on our radio and we'll see where it is and we'll cross our fingers but it lands in a field and yeah great thank you very much for listening that's it and we have time for questions if anyone has questions oh we have a microphone for people with questions that's great can you put up the slides on the schedule for the talks so we can look at them offline yes good idea I'll put the slides up and then you can see the pretty photos yourself that will be great when is the balloon going up? I don't know when I'll put that on the schedule have any ideas when? it's looking like Sunday apparently so how much does it cost to set up your own reg to be launching your own balloons but what's the sort of entry level for this 200lb gets you everything you need to get a balloon in the air and track it and so forth possibly cheaper these days if you go through a much smaller balloons and very small payloads but like it'd be safe within a few hundred pounds and that includes cameras and helium and so forth just curious what's the do you have to seek permission like the flying thing? I should probably mention that so if you want to launch a big balloon you have to ask the CAA and they take a little bit of chasing and it's usually about a month and you can say we'd like to launch this day and maybe this day and they say ok but as long as it doesn't go too near this airport and you have to get the permission back before you launch otherwise it is illegal and you're a bad person if your balloon is quite small less than two metres in total in closing diameter for the duration of a flight then you don't need any permission at all and you can just let it go however we have in fact secured permission for a large balloon from this site over the weekend but I don't know if we have any large balloons to launch oh we do, so we might be launching some large balloons as well there's one other detail which is if you're a hobbyist and you just want to launch a balloon and you don't want to try and get your own permission there are two sites around the country both in Cambridgeshire where we have this kind of rolling 24-7 permission all year long so if people want to rock up we can usually arrange to let them launch their balloon what does the guy who did the what's it called the 70 launches, what did he use for tracking so he used a combination of things, we've got cleverer and cleverer as time goes by primarily there's the built-in system which we use over the UK and that works great in the UK and there are more and more people running that software in Europe and a couple in America and it works quite well but for most of the world people aren't going to be running the software or listening out for your balloon so there's a different thing called APRS the amateur packet radio system which if you're an amateur radio operator you'll know all about and you can't use it in the UK it would be illegal because we're not allowed to use our amateur radio licences airborne but if you're outside of the UK and you don't look too closely at the fine print on the reciprocal licence you can probably maybe use your licence airborne and so he's been doing that and occasionally Eratam's whined at him on Twitter and he ignores them so like there are ways around it you can get say I have an extra American licence now because I'm launching a rocket with a radio in America and then I can use that anywhere that's not the UK and that also lets me operate airborne probably but yeah APRS works really well for this kind of thing if you're allowed to use it so the balloons which have been sort of gone all the way around the earth yep how long will it take them to just deflate entirely it's a really good question and no one's quite sure the theoretical rate at which we're leaking helium is really low because this plastic film is very impermeable and so far they haven't changed altitude which you'd expect them to do if they were leaking helium so it seems like more likely the UV degradation will cause the plastic to weaken and then the plastic will just pop because it won't be able to take pressure but we're not really sure yet how much protection against the cold and other environmental factors up there does the hardware need this is a thing a lot of people kind of trip up on I've seen so many times you know the kind of powder hand warmer things little sachets, you've got the mini gloves to keep your hand warm people go oh it's very cold up there my electronics will get cold we'll put one of these in two problems they need oxygen to work which you don't have and secondly there's actually so little air that the electronics can't keep cool you don't get convection cooling and the electronics are generating heat so usually they end up quite warm by themselves just because they can't cool down so most people fly fairly exposed payloads and it works just great people will tell you that lipos don't work at minus 20 and maybe they're right but it looks like they're not actually right because they work just great how does the leakage rate change between helium and hydrogen so I'm not entirely qualified to answer you'd think maybe hydrogen is a much smaller molecule than helium because it's only got one or two gobbins instead of four gobbins but actually hydrogen exists as two so it's much bigger so in fact helium leaks much quicker is the short answer can you tell us a bit about the guy that's doing around the world balloons you said it's only weighs 13 grams and you're comparing things with raspberry pies and things which are a lot heavier has he built it all himself or is he using something commercial or what so he's built it all himself I don't know I think it would be fair to describe him as somewhat media shy his website is a little sparse and he occasionally winds about people trying to talk to him on these other ISE channels he's built all the electronics himself which is a fairly normal thing to do and he's worked on getting it as light as he reasonably can so it's a very small PCB it's got a few small surface mount components and nothing unnecessary he does this for his day job as well he assembles electronic systems and things for F1 cars and things I don't know very many details about his real day job but he knows his electronics inside out so he's built it all himself and pretty much he just came in looked at what everyone else was doing and went this is nice well the results speak for themselves I suppose could you tell us about the predictor software that you use yeah I'd be happy to the predictor software is this great web tool it's available online you go to predict.hub.org and you can type in where you're launching from and it will show you where the balloon goes by downloading a whole load of wind data for every point on the surface of the earth for every time for the next two weeks which is a heck of a lot of data and it gets this from the American nowhere web agency people who run a big supercomputer model to work out where the wind is blowing and then it runs some clever integration methods to say your balloon is here and we know it's going to ascend at this descent rate based on how much helium you've put in and so forth and it will burst at this altitude because that's when the balloon gets so big it pops and then it will descend at this rate we hope because that's how thick the atmosphere is and it's got this parachute say and then it lands and the software has kind of changed a lot about how people can do ballooning it means you can launch and be confident you're avoiding airports and cities and jet fighters who are training that was really awkward like cutting down a tree was no problem but the later CIA investigation was so it's a good tool it gets used like 2,000 times a day by people all over the world there's a really great photo that I probably can't show you of every place anyone's requested to launch from and it's basically a population density map of the earth anywhere there are people we've got people requesting these predictions and also the new version of the predictor because rewriting everything from scratch is always the best idea is being deployed in a couple weeks and it's even cleverer you can do fancy things like say I'm going to launch sometime in the next two weeks show me where all the possible landing locations are and I'm going to launch and I can change how much helium I can put in to avoid going in the sea so also it's in python and mad fast it's faster than the sea version it's fantastic, it's like 2 milliseconds per prediction so it's cool what do you think about Facebook and Google and their Wi-Fi balloons do you think that's realistic? yeah, there was a UK house conference like two weeks ago and we had one of the guys who's consulting for Google Loon give us a talk about Google Loon and it seems like it's working really well and Google Loon stay up for like a couple months and they're launching they've got launching down we saw a video of them kicking off these balloons and it's like they just throw them out every hour or so and they mesh perfectly and they provide Wi-Fi so it seems to be working great they claim they can control where the balloons go by making them go up and down which is entirely believable whether it becomes a feasible commercial project I'm not sure, it seems really expensive but the technology definitely all works could you tell us about some of the worst flights where things have either exploded or run into things or something like that some of them which ones I quite like there's a military base called RAF Fetford and we came down while they were doing some helicopter training of Chinooks and they were most displeased and it landed in this really tall tree and we were like, oh no, our thing's in the tall tree and this is the one where they were like, oh yeah, we'll cut that down for you no problem and got out like a huge chainsaw cut into a tree, army jeep and then set the CIA on to us there's this big investigation where they're like, should we have done something differently are we liable, what would have happened if we hit a helicopter would that have been really bad answer, yes and eventually they concluded that really we were probably doing everything legally and fine and the guy running the investigation was like, also this looks really cool can I see some of the photos you took so that was a happy ending are there any other I think the one that landed in central London was pretty bad, it actually landed in Pineham Park and Richmond Park and we knew someone who was out walking in Richmond Park that afternoon so we picked it up for us which was great UK House 1 I'm getting a shaking head I probably shouldn't mention that one there were children and make sure they're fairly soft and well padded and nothing too bad all one happened to someone else, I can definitely talk about this landed on a power line and they had to shut down power to an entire village for an afternoon to get the thing off again which was a huge chunk on a certain media company's insurance claim that must have been really awful that I think later landed in the middle of a train track and you suddenly understand why they put all those emergency numbers on the bridges to phone the train companies and have them stop for trains any suggestions oh yeah we had another fun one where we came down and looked for a very long time like we'd land on a major motorway which would have been so awful turns out fun fact 1% of the surface area of England is major roads which means you launch 100 balloons you expect one of them to land on a major road hasn't happened yet this balloon was drifting straight over a major road and it really really looked like it would land on it and cause a surge of trouble then at the last moment it veered off to the side and the construction worker on top of the building the best part is the videos cameras were still running so we had this great video of it swinging by not quite hitting him and the guy goes oh what's this, picks it up we've written harmless scientific experiment on the side he goes harmless less fortunately he then proceeds to open up a box doesn't contain the video cameras and rummaging around for freebies as he calls it he goes oh batteries takes the batteries out, realises it's a GPS tracker puts it back in the box still has included what the other box is a video tracker so we've got this great video of him then carrying it to his boss and he's like what shall I do with this and the boss is like oh yeah and then they realise it's got a phone number and they debate whether they should call us they decide we'll probably some stuck up and don't call us and then we turn off at their office a few minutes later and we're like how could we have our balloon back please it's inside your office so I later edited that into a video compilation on YouTube where we blurred out the guy's faces so I think that's probably enough bad launch stories but like maybe if you find me late at night in the bar I can tell you were the one about the children hi, hello, hi I was curious about what you were saying before about if everyone put their own balloons up and then you could share your connection with other people and connect to your home network on the other side of the world could you expand on? I think that's probably enough bad launch stories so the basic idea UKHast.net is the thing that's been set up for it and you run these radio modules RFM 169B they've got some part number and they automatically form a kind of network but anyone of them transmits anyone else but here's it receives it and we have a simple protocol that lets them repeat anything they hear so the actors kind of repeat the stations was a time to live in the packet time to live I suppose so packets only get repeated so many times and then the balloons are just another note and the idea is you have one in your garden that sends back logs temperature or humidity or something roaring and you have one in your house that's plugged into your computer over USB and that's enough to get anything it receives sent up to the internet and then the internet has a map and you can see everything and even be perceived and the really key idea is if a balloon goes overhead it should have line of sight with your network on the ground and the balloons they could all see each other and send packets between them and it's not clear how useful it would be but it would be really cool and so people are pursuing it and as I understand it there are or will be several of these nodes around the site here and maybe we'll get the badges doing it as well maybe okay are we all questioned out that's great because it's now 1446 so we are one minute over time thank you all very much