The project is HighFlyer at SourceForge. I put up the page a long time ago and then hit a snafu among the partners. That snafu is past now, so all I've got to do is remember how to post the code through CVS. 8)
One word of warning, though. The code in the simulator I have right now for dynamic lift is weak. Most of my work on that front has been with spreadsheets. I want it in the simulator, though. I also want to make it available for kibiitzing and/or help.
I have no desire to work under our vehicle if it is filled with hydrogen until we have much better safety procedures. The worst that can happen to me with helium is I have to walk away to where there is breathable oxygen. When my voice gets squeeky, it's time to walk away. 8)
We will use hydrogen is some capacity later. We intend to be flying fuel cells, so hydrogen will be very convenient in other ways.
I am the teams physicist if you have any direct questions. I won't answer everything because a competitor with more cash could displace us, but I do intend to open source the simulator I've built.
We've already tried a shotgun on the outer fabric. You have to be pretty close to get through. The envelope flexes and absorbs the impact if you are too far away.
What some of us are thinking of is taking a few of our orbital ascenders and rearranging them in a big torus once we have them up there. They wouldn't come back down anymore. Bring up some cabling for spokes and leave the old docking equipment in the center and we have.... 8)
The world would be a very different place if we hadn't dropped airship development. There is no doubt about that.
The shape of the airships is significant. Think of them as large flying wings. A cross section through the lift envelope would produce an outline shaped like an airfoil.
I have little doubt that the materials exist to do all this today. My only doubt is whether I can get access to engines with enough power to do the job within out budget. The ion engines we vaguely describe are our third level choice. We prefer one particular engine for first place but it's still classified as far as I know.
Re:No way. Unfortunately. Way too much drag
on
Blimps... In... Space...
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· Score: 2, Informative
Two gold stars for you!
We will be using dynamic lift. That is an absolute must. We will also be bringing the truss structures inside the envelope, so the drag coefficients should become more comparable to regular flying wings.
The heat loading issue on the way back down is no worse than it is on the way up. We can go into a high drag profile at a very high altitude and spread the loss of kinetic energy over a very long time frame. Skin heating is proportional to the power dissipation rate, so a long time frame keeps that number low.
Tension lines in the skin of the load bearing material are the solution we have in mind. For lower altitude vehicles we use rip-stop nylon for load bearing and mylar for gas containment. The mylar cell floats inside the nylon envelope.
The window we describe is both a permit and money issue.
1. It's not really fair to keep the air traffic control people on their toes for a big, lumbering airship working its way up through and back down through their airspace, so we have limited the flight window. 2. We will also have our crew on sight to fly this thing. Some of them are burning vacation days away from their day jobs and we are burning cash keeping them in motels and feeding them all. There is a limit to how long we can do this too.
The airship we intend to fly is one of the lower atmosphere varieties, so the concept of launch window like you would use for orbital rockets doesn't apply. Aircraft takeoffs and landings are more in line what what is going on.
The physics is a bit more complicated than some here realize. The airships are shaped like wings for a reason. We intend to use both buoyant and dynamic lift for each of the Ascenders.
And... yes... Drag is a significant issue. The power you need to increase the speed depends directly on the drag force. Obviously we must use dynamic lift as much as possible to fly high enough for our engines to be able to add the delta-vee we need. If we don't have enough power, it can't be done. If we do, it can be done. It's that simple.
Also, be aware that the ion engines we have in mind are the third place finishers for job. The first place engines are ones we can't talk about yet without spending time in jail. 8)
The hoops were never easy to jump through. The trick is to have someone on your side. That hasn't changed and probably won't until there is more credibility and success within our industry.
Do not treat the US Federal Government as a monolithic entity. Some parts are very enthusiastic about private sector launch capability. Other parts feel threatened. Like any other business, one must learn navigate the sea and avoid the shoals and sharks.
The difference in claims usually comes down to whether one can verify their flight or not and how they do it. I'm the one who fit the curve on the JP Aerospace flight that went to just above 72,000 feet. We got plenty of GPS data, so the curve had to fit a lot of 'reality.' We launched from a balloon at around 29,000 feet using a K-class motor with a moderately long burn.
H2O2 can be shipped in low concentrations and then distilled on site. The method for getting it to about 85% is very simple.
We don't use liquid fueled engines yet though. We just strike a bargain with the supplier to arrange picking up the fuel slug in a legal way and transporting it in a legal way.
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The project is HighFlyer at SourceForge. I put up the page a long time ago and then hit a snafu among the partners. That snafu is past now, so all I've got to do is remember how to post the code through CVS. 8)
One word of warning, though. The code in the simulator I have right now for dynamic lift is weak. Most of my work on that front has been with spreadsheets. I want it in the simulator, though. I also want to make it available for kibiitzing and/or help.
No Sputnik needed. Just buy t-shirts, hats, and so on. Volunteer to help if you can. Be patient otherwise because we won't stop.
Drop me an email and I'll send you a phone number. Try more than once in case my spam filter gobbles it.
bingo.
I have no desire to work under our vehicle if it is filled with hydrogen until we have much better safety procedures. The worst that can happen to me with helium is I have to walk away to where there is breathable oxygen. When my voice gets squeeky, it's time to walk away. 8)
We will use hydrogen is some capacity later. We intend to be flying fuel cells, so hydrogen will be very convenient in other ways.
There is something subtle they've missed.
I am the teams physicist if you have any direct questions. I won't answer everything because a competitor with more cash could displace us, but I do intend to open source the simulator I've built.
We've already tried a shotgun on the outer fabric. You have to be pretty close to get through. The envelope flexes and absorbs the impact if you are too far away.
What some of us are thinking of is taking a few of our orbital ascenders and rearranging them in a big torus once we have them up there. They wouldn't come back down anymore. Bring up some cabling for spokes and leave the old docking equipment in the center and we have.... 8)
Our pilots have already had kids... all except one.
Besides, the early flights are all unmanned.
The world would be a very different place if we hadn't dropped airship development. There is no doubt about that.
The shape of the airships is significant. Think of them as large flying wings. A cross section through the lift envelope would produce an outline shaped like an airfoil.
I have little doubt that the materials exist to do all this today. My only doubt is whether I can get access to engines with enough power to do the job within out budget. The ion engines we vaguely describe are our third level choice. We prefer one particular engine for first place but it's still classified as far as I know.
Two gold stars for you!
We will be using dynamic lift. That is an absolute must. We will also be bringing the truss structures inside the envelope, so the drag coefficients should become more comparable to regular flying wings.
The heat loading issue on the way back down is no worse than it is on the way up. We can go into a high drag profile at a very high altitude and spread the loss of kinetic energy over a very long time frame. Skin heating is proportional to the power dissipation rate, so a long time frame keeps that number low.
Tension lines in the skin of the load bearing material are the solution we have in mind. For lower altitude vehicles we use rip-stop nylon for load bearing and mylar for gas containment. The mylar cell floats inside the nylon envelope.
The window we describe is both a permit and money issue.
1. It's not really fair to keep the air traffic control people on their toes for a big, lumbering airship working its way up through and back down through their airspace, so we have limited the flight window.
2. We will also have our crew on sight to fly this thing. Some of them are burning vacation days away from their day jobs and we are burning cash keeping them in motels and feeding them all. There is a limit to how long we can do this too.
The airship we intend to fly is one of the lower atmosphere varieties, so the concept of launch window like you would use for orbital rockets doesn't apply. Aircraft takeoffs and landings are more in line what what is going on.
The physics is a bit more complicated than some here realize. The airships are shaped like wings for a reason. We intend to use both buoyant and dynamic lift for each of the Ascenders.
And... yes... Drag is a significant issue. The power you need to increase the speed depends directly on the drag force. Obviously we must use dynamic lift as much as possible to fly high enough for our engines to be able to add the delta-vee we need. If we don't have enough power, it can't be done. If we do, it can be done. It's that simple.
Also, be aware that the ion engines we have in mind are the third place finishers for job. The first place engines are ones we can't talk about yet without spending time in jail. 8)
We have all read it. I read it twice to make sure I learned the important lessons.
It will not stay at $2000/kilo or more for long now.
I doubt the Chinese will be concerned about the economics for a while though.
The hoops were never easy to jump through. The trick is to have someone on your side. That hasn't changed and probably won't until there is more credibility and success within our industry.
Do not treat the US Federal Government as a monolithic entity. Some parts are very enthusiastic about private sector launch capability. Other parts feel threatened. Like any other business, one must learn navigate the sea and avoid the shoals and sharks.
The difference in claims usually comes down to whether one can verify their flight or not and how they do it. I'm the one who fit the curve on the JP Aerospace flight that went to just above 72,000 feet. We got plenty of GPS data, so the curve had to fit a lot of 'reality.' We launched from a balloon at around 29,000 feet using a K-class motor with a moderately long burn.
H2O2 can be shipped in low concentrations and then distilled on site. The method for getting it to about 85% is very simple.
We don't use liquid fueled engines yet though. We just strike a bargain with the supplier to arrange picking up the fuel slug in a legal way and transporting it in a legal way.