rockoon rocket
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yes i live in the United States
A K730, for example, might get there if the rocket were small enough and the dry mass light enough. That's a 6 lb rocket. If you can make a nice carbon fiber launch tower, you might be able to keep the balloon's suspended mass under 10 lbs. That's probably around 1/6 the minimum lifted mass you'd need for an N5800.
If I ever do a space shot, it will be optimized to find out what is the smallest, cheapest rocket that can do the job. A camera will be the only payload other than GPS and altimeters. And I'm not sure about the camera.
There is no need for hardware if it cannot be launched.
Like with everything, the first step should be to do it on a smaller scale, like launching a rocket from a balloon at 50 feet, just to test the systems of wireless launch, tracking, dual deployment, stability of an unmounted launch tower, etc.
The weight of the gyroscope and counter rocket spin from the gyro are two major issues for a small rocket using this method. To raise money for these ventures, people demand to see video evidence that is clear and with little motion. Joe Barnard is currently testing a fin tab system using MEMS gyros and small servos that shows great promise for supersonic flights under 120,000 ft. Hot or cold gas reaction control motors are necessary for attitude control above 120,000 ft.Okay if stability is a problem for a small rocket at that altitude, what about installing a high-speed gyroscope? I pondered this myself and built one from a small DC motor and stuck it in the nose cone but never got a chance to use it
Okay if stability is a problem for a small rocket at that altitude, what about installing a high-speed gyroscope? I pondered this myself and built one from a small DC motor and stuck it in the nose cone but never got a chance to use it
Wouldn't it be possible to just borrow one from a model airplane or quad copter? I don't know how many gees they can handle, though I'd guess it's in the neighborhood of 10 or 20. One could use it with vectored thrust or one of the other tricks that people use for landing model rockets under power. Once the motor cut out, if the air was thin enough that fins didn't work, maybe it wouldn't matter if the rocket was going sideways.The weight of the gyroscope and counter rocket spin from the gyro are two major issues for a small rocket using this method. To raise money for these ventures, people demand to see video evidence that is clear and with little motion. Joe Barnard is currently testing a fin tab system using MEMS gyros and small servos that shows great promise for supersonic flights under 120,000 ft. Hot or cold gas reaction control motors are necessary for attitude control above 120,000 ft.
Which is why I mentioned guidance, though of course guidance is a can of worms too.I always say this.
The FAA will ask……
How are you keeping the rocket in the waivered area for the entire flight? Drift under balloon, off vertical launch, drift under parachute.
BALLS has the highest wavier the FAA can issue, 150 km. The radius (when I was doing it) was 17nm. Not so far adding up the possible drift.
Are you saying rocket scientists are not as smart as the people who develop electronics for quad copters and model airplanes? And not smart in a very particular way, since powered landings have been done by little rockets. Seems to me the latter is much more of a problem.Guidance in most cases is just a dream.
How will it be developed and tested under real conditions.
The current MEMS gyros require TVC, fin control, or a hot or cold gas thrusters to maintain attitude control. TVC only works during the motor operation and the coast phase of the flight could be 10-20 times longer than the thrust duration. Fins only work in the denser atmosphere, so we are left with hot or cold gas thrusters for space applications or spin stabilization without video. I do not know of any amateurs working on hot gas micro thrusters. I have worked on CO2 cold gas thrusters with some success.Wouldn't it be possible to just borrow one from a model airplane or quad copter? I don't know how many gees they can handle, though I'd guess it's in the neighborhood of 10 or 20. One could use it with vectored thrust or one of the other tricks that people use for landing model rockets under power. Once the motor cut out, if the air was thin enough that fins didn't work, maybe it wouldn't matter if the rocket was going sideways.
Unless we are talking about really tiny rockets, I don't think 3 grams would be all that much of a problem, though obviously vectored thrust would add more weight.
https://www.spektrumrc.com/product/as3000-as3x-flight-stabilization-module/SPMAS3000.html
I don't know what it would do to the legality, but one might also set up the guidance so the rocket slants back toward the original launch point as it goes up, and have it plunge straight back down until reaching a reasonable altitude. This ought to reduce the recovery radius.
The following may contain errors. I don't do these calculations much.
The following site says that latex balloons can get above 130,000 feet! Let's be pessimistic and assume 120,000 feet. At that height, air density should be only about half a percent of that at sea level.
https://www.stratoballooning.org/faqs
https://www.digitaldutch.com/atmoscalc/
Neglecting air resistance, and also neglecting the slight reduction of g with increasing height, a 5 lb rocket, or let's say a 2.3 kg rocket, of which 1,8 kg was fuel, I think you'd need something like 3,100 N-s to get to 330,000 feet from 120,000. I'm not so sure about the following, but I think that might imply a required specific impulse of something like 215. So MAYBE an amateur could achieve that. Of course, the empty motor, instruments, airframe, etc. would all have to weigh 0.8kg. Or one could go to a two stager. We should remember that a lighter airframe may be possible, since, if I'm not mistaken, max q will be less and fins will not be required or useful. A barometric altimeter might not be much use, either.
Those who make quadcopters and model airplanes can test at operating altitude.Are you saying rocket scientists are not as smart as the people who develop electronics for quad copters and model airplanes? And not smart in a very particular way, since powered landings have been done by little rockets. Seems to me the latter is much more of a problem.
So the air can be thin enough that fins won't work, but thick enough to create significant drag? That seems counter-intuitive. I am not familiar with TVC mechanisms. Could one make a motor with a long end burning section, like a slightly overpowered delay charge, to allow TVC most of the way to apogee?The current MEMS gyros require TVC, fin control, or a hot or cold gas thrusters to maintain attitude control. TVC only works during the motor operation and the coast phase of the flight could be 10-20 times longer than the thrust duration. Fins only work in the denser atmosphere, so we are left with hot or cold gas thrusters for space applications or spin stabilization without video. I do not know of any amateurs working on hot gas micro thrusters. I have worked on CO2 cold gas thrusters with some success.
It does matter if a rocket starts to tumble. Kip Daugirdas's rocket missed 100km space by 10 km due to his rocket tumbling above 200,000 feet. The old Viking #6 only reached 40 miles due to it losing a fin after burnout.
The success rate for rockoons is not 100%. The IGY rockoons were around 64% and Project Farside was 67%.
Doesn't TVC work about the same when the air gets thinner? If you have to do something before you do it, there may be a problem. Maybe work up to it in stages? Hasn't NASA already solved these problems?Those who make quadcopters and model airplanes can test at operating altitude.
A rocket to be launched at 100k plus it is difficult to test under those conditions.
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