Ask Derek Deville About High-Altitude Amateur Rocketry 148
A few days ago, we posted about Derek Deville's mind-blowing high-altitude rocket-launch in the Nevada desert. His 14-foot, GPS-equipped (four GPS units, actually) home-made rocket ("Qu8k") managed to hit 121,000 feet, an effort that took more than a trip to the store for more Estes "D" engines. Derek has graciously agreed to answer questions about Qu8k and other rocketry projects. Please confine your questions to one per post, but ask as many as you'd like.
ATF? (Score:4, Interesting)
How has the relationship with the ATF and other government agencies affected amateur rocketry since 9/11?
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How has the relationship with the ATF and other government agencies affected amateur rocketry since 9/11?
Thats pretty well documented, with them F-ing around for about a decade until the courts told them to cut it out just a year or two ago. Much better now.
I'd be interested in his personal experiences with the BATFE.
Second Try: ATF? (Score:2)
You're right -- the story at the national level is well-known. I was trying to give him a forum to share his personal experiences, but I didn't want to bias the question by assuming he had any, and ended up not asking the question I really wanted to ask. Self-editing never works.
Let me try again:
How have the BATF (now the BATFE) and other government agencies affected your enjoyment of amateur rocketry since 9/11?
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My guess is that relationship went south quite a bit earlier - around the time a New Zealand hobbyist was offering the schematics for a DIY cruise missile that could be built by any geek with a basic toolset and $5k spare change. That episode... ...freaked out more than a few governments, as I recall. It may not have used rockets, but that's immaterial. The guidance system is the only technically difficult part of this sort of project and is the chief reason the US and USSR were in the space race to begin w
GPS (Score:2)
Civilan GPS has limits in speed and or altitude both of which you exceded. How did you measure altitude and speed? Air pressure?
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Those limits are voluntary and vary from manufacturer to manufacturer, and many devices ignore those artificial limitations. Even if the restrictions are honored by a given device, the firmware can often be modified to remove those restrictions, and it is still perfectly legal for domestic use; it just can't be exported without an export permit since it is then regarded as munitions (much like high-grade encryption back in the day). Lastly, the export restriction applies only to devices to devices when spe
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Also from talking to balloon guys, the speed limit would not be applicable on the way down, and the altitude at which they "cut back in" is high enough that long distance reception is still pretty easy (its not like they cut out at 1000 feet AGL). I have not heard of any GPS engine/module that required power cycling when limits were exceeded, soft fail...
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It's suborbital, not orbital, and it never leaves US airspace, so no.
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At which height does US airspace end?
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I would imagine it would be the FAI definition of 100km being the recognized boundary of the atmosphere and space, even though the atmosphere doesn't truly end until past 10,000km.
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The US grants Astronaut wings for a flight to 50 miles or around 80KM by international law probably 100km.
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I worked for a GPS company in the early 1990's. Due to the first Gulf War, some of our civilian marine GPS systems were strapped into fast jets and worked perfectly well within the performance envelope of a Tornado fighter/bomber....
Today, even if limits have been put into the sets, its probably not a difficult matter to look in the code for the appropriate constants and change the firmware.
Ours ran on an 8MHz 68000, I'm sure your average GPS phone nowadays has a much more capable CPU.
Obvious Question (Score:1)
It can go 36 kilometers up or further sideways (Score:1)
Did you take precautions in case the rocket turned sideways or were you just hoping it wouldn't? Big rockets always have remote controlled self-destruct. Yours too?
So... (Score:2)
When people ask what you do in your spare time. How do you answer them without their eyes glazing over? Or worse listening to you intently then asking you join their Militia or just reporting you to the FBI?
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When people ask what you do in your spare time. How do you answer them without their eyes glazing over? Or worse listening to you intently then asking you join their Militia or just reporting you to the FBI?
Closely related, you must work with the BATF at these levels; I know that personally from my much smaller work decades ago back when a "G" size engine was a big deal... Anyway, the BATF is famous for trying to run an undercover op of gun smuggling that is so big that they "took over" the entire market such that all illegal gun traffic came from the BATF itself. The reason for bringing this up, is I wonder if the BATF guys ever tried to entrap you or lure you into a conspiracy WRT to storage and use of rock
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Public support? (Score:5, Interesting)
Back in the 1950s and 1960s in the US, model rocketry was promoted as a way to interest youth in science and technology and, therefore, strengthen and defend the nation. However, amateur and, to a lesser extent, model rocketry are today seen by much of the public as a dangerous technology that should be suppressed, to keep it out of the hands of dangerous terrorists. How can the rocketry community regain public support?
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What are you on about? Frigging Walmart sells model rockets and engines.
Yeah well I wouldn't use what Willing ALlah's MARTyrs sells as an example of something safe!
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What are you on about?
Just one example [space-rockets.com] of the FUD the industry has had to deal with.
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Mostly by the model rocketry industry as a way to bandwagon on the public's brief infatuation with space travel.
That's what the tinfoil
Recovery Tracking (Score:2)
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The pictures on his web site show an APRS transmitter.
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The pictures on his web site show an APRS transmitter.
That means somewhere out there is a findu.com link to lookat it... assuming at altitude he was within range of an igate, which even at altitude might be a challenge in the middle of nowhere. Anyone have the link at findu.com?
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On the balloon I helped send up a couple weeks ago, we used APRS transmitting location from a Garmin GPS18.
Oldest and newest flight technologies. (Score:5, Interesting)
Balloons seem like an excellent and flexible launch element which could offer a ton of altitude and avoidance of at least some friction. Have you heard of or considered this?
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Not to answer his question for him, but if you are interested in this, on the AR list there are a handful actively pursuing this ( including JP Aerospace which you referenced ). For the Carmack Prize, this would not have helped. It would have had to achieve 100k ft from the point in which is launched from the balloon, which is at such thin atmosphere actually hurts rather than helps in this case.
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Spin baby, spin!
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"Balloons seem like an excellent and flexible launch element..."
Have you any idea how big those balloons would need to be for that weight?
Did you check the helium prices lately? It would cost a fortune!
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Also if you intend to have the landing within 3 miles, like this guy did, the balloons would have to climb darn near supersonic to get up there before they drift sideways too far.
Also the gyrostabilizers or whatever to launch it when its pointed perfectly up are going to be very complicated / heavy / expensive.
Finally you have to limit the rocket design to tolerate / survive getting tangled in balloon lines.
balloon launching just kinda sucks as an engineering design, when its so much simpler to just make a
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Would it be possible to use a balloon to get to 30+km, then turn it around and use it as a rocket platform, launching a rocket to, say, the moon? It wouldn't have to be a very powerful rocket (and thus steerable like in the game Asteroids).
I'm probably being naive here...
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Rockets are actually pretty old as far as flight goes. Probably predate ballons :)
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The problem with balloon launches is the same problem with mothership launches like the SpaceShipOne. Once you get up to altitude, and modest speed, so what? The White Knight gets you to around 15km and 200m/s. Balloons get you to around 30km and 0m/s. Meanwhile, LEO starts around 150km and 8000m/s, which at that altitude is only good for a couple days before you re-enter. They can get you a decent chunk of the altitude, but are nowhere near the velocity requirements. Remember, fuel and launch mass va
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Balloons aren't very useful if you're aiming for orbit, but for amateur rocketry where we're just trying to get something crazy-high and take a few pictures before a ballistic/chute reentry, it's likely a viable technique. This rocket achieved 37km from the ground. How high would it have gone if they'd launched from 30km and boosted the whole way with much lower air resistance? The balloon might limit you to a smaller rocket, but I'm certainly interested to find out what's possible!
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White Knight gets you most
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Launch flexibility is the only thing air-launch systems have going for them. Systems like Pegasus can launch from anywhere in the world, at any time, in nearly any conditions. Their low cost per-launch means a lot of smaller projects can afford to be the primary payload on a launch, and get priority orbit selection, rather than get stuck on whatever orbit inclination someone else wants to use. That said, it is one of the most costly launches per unit mass in existence, and as you stated, balloons lose ma
Towards Orbital Rocketry (Score:2, Interesting)
Are there plans or even a roadmap you could lay out towards orbital rocketry by serious amateur groups?
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what are the laws about this (Score:2, Informative)
What rules & laws do you have to follow launching a rocket like this? With so many aircraft in the air im sure there must be
Fuel (Score:2)
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There are many many formulations but mostly it comes down an oxidizer, fuel and a binder.
Lots of engine builders use a variation on the formula for the shuttle solid rocket boosters (SRB's) and some use the exact same formula.
See the Wikipedia article about Solid Fuel Rockets [wikipedia.org] for mor information.
Attitude Control (Score:2)
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The vast majority of amateur rockets are passively stabilized.
Center of gravity above center of pressure.
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Center of gravity above center of pressure.
This works perfectly in theory, but maintaining this is hard. Most amateur rockets have a 'good enough' approach to stabilisation. The bigger the rocket gets, the more variation in CoM inline with thrust and the harder the problem gets. See the Scandinavian amateur rocket a few months ago that ended up pitching by something like 70 from vertical.
Qu8k Construction Materials (Score:4, Interesting)
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Also what did you use for the shade over the video camera that apparently melted during the boost phase?
Says in one of the videos it was made of "plastic."
flight control (Score:2)
Re:flight control (Score:5, Informative)
All of the big high altitude rockets have on-board computers and most have video cameras etc. On launch they go off a rail since there are no active flight controls. The accelerate at well over 10g so they are up to speed very very quickly. Once they clear the rail they can drift but at the speeds they are going up at not so very much. Almost all the drift occurs before apogee as it is coasting or at apogee as the rocket noses over and start the trip back down. Additionally for those kind of launches you wait for the least amount wind possible.
Most of these types of rockets transmit telemetry on HAM frequencies. The operator can watch real time events from the on-board computer for altitude, speed, chute deployment, location ( from the on-board GPS ), ascent stage separation, sustain stage ignition signal, sustain stage burning and all sorts of things.
As the computer detects altitude decreasing and sufficient speed has been attained the computer deploys a drogue parachute which has just enough drag to keep the nose pointed straight down so the rocket accelerates to terminal velocity very quickly.
At a preset altitude either the main chute is deployed or another larger drogue to decelerate the rocket to a speed where the main recovery chute will then deploy without either shredding or tearing the rocket to bits.
Most model rocket engines ( like an estes ) have a small charge at the top of the motor which has a time delay fuse that is lit when the motor ignites. The charge is then ignited which has just enough pressure to cause the two halves of the rocket to separate and deploy the recovery parachute at or just passed apogee so if you have any amount of wind aloft your rocket will ride the wind as it descends at from 2000 or so feet if you have a slow descent it could drift quite a ways.
Rockets like the one in question are very expensive to build and the cost can push up to $5K to $10K depending on how exotic the materials are. Launching those can easily hit $500.00 per launch or more depending on who your motor builder is and other factors.
Hurdles (Score:3)
What were some of the hardest hurdles you had to overcome to get this working?
GPS.... (Score:2)
.... what's the solution? You had 4 GPS receivers and none of them tracked your rocket at altitude. Obviously rocket grade GPS exists but with military export controls on them. Is this a spot where DIY's could hack together a GPS module that handles the vibration and acceleration?
Time and Materials cost (Score:1)
Machinery (Score:4, Interesting)
I looked at your website pictures; clean shop (cleaner than mine, anyway); Curious what type of equipment you used to build it... I see a bridgeport-style knee milling machine, a large unidentifiable lathe with a quick change toolpost. Chinese or classic American heavy iron? Nice smoke off the carbide (carbide, unlike HSS, can be pushed hard enough to make the cutting oil burn without wearing the cutting edge) Looks like all manual machines, no CNC? TIG welding the aluminum or ? Did you CAD it all up or build as you get parts? Is something like this rocket light enough to manhandle around the shop or are their engine cranes involved, or a custom cradle of sorts?
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I'm hot for a 3d printer because I want to print foundry patterns. They are a PITA to make by hand, its agonizing when one breaks while ramming the sand around it, getting the sprue placement, draft allowance, and shrinkage factor correct is a struggle, and the only way to share foundry patterns involves UPS and shipping costs. On the other hand, if I could just print up some internet dude's perfectly optimized pattern... Doesn't help with cores, and things like shake mean the ideal shared pattern is pro
Costs and resources. (Score:2)
I'd really like to get a sense of the resources (time, machinery, and dollars) went into the project. Obviously your biggest non-monetary cost was labor, but what did you pay out of pocket? How many resources were donated (i.e. specialized machinery)?
Plans for a multi-stage version? (Score:3)
Payload and G-force (Score:2)
What was the weight of the payload? (i.e. the combined weight of the video cameras). Can we include a small mouse astronaut on the next flight, if we substitute the 2 video cameras with one smaller one?
Would it be possible to mount a second stage on top of the exisiting rocket, say a small Estes model, and launch that from 120,000 feet?
Those socketed PLCCs on the controller board (Score:2)
Tripoli or NAR (Score:2)
Tripoli or NAR for YOUR sanctioning / certfication body, and in comparison you'd recommend to a noob to start with Tripoli or NAR? Or is the experience with both groups so similar its kinda like miller lite vs bud lite (gotta look at the label to tell them apart)
In Soviet Russia (Score:1)
Amateurs rocket YOU!
Design software (Score:2)
Did you use integrated all in one design software, or a buncha spreadsheets, or a buncha equations in octave/matlab/mathematica, or paper -n- pencil?
In light of above answer, complete this sentence: My project would have been easier for me if the computer/technical/nerdy guys on /. "did this" ...
Inappropriate answer would be "DDOS the BATF" or "launch cowboy neal" I guess I'm expecting software development ideas.
Testing (Score:2)
How did you test this stuff? both mechanically, electrically, etc? Big homemade wind tunnel, or did you freeze the electronics in dry ice to see what happens, or ?
What got you in? (Score:1)
Those are some pretty massive rockets, ever work on stuff like model helicopters and RV cars? To get to that level where did you have to start? Did you go to wal-mart and purchase a kit and go from there, or get a blow torch and start creating rocket fins?
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Make friends with a college chemistry professor. Manufacturing the parts is difficult, but with a bit of mechanical skill, and some initial oversight to teach you proper safety procedures around heavy machinery, most people could get by. The design is "rocket science", but to be honest, it's really just a bit of math and a lot of experience. Pick up some books on rocket propulsion and fluid mechanics, read them, and then read them a couple more times.
The hard part is the manufacturing of the fuel, and by
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The best thing to do is to become a member of NAR or Tripoli (the two hobby/amateur rocket associations) and pick up some magazines on design and finishing from their resources. For a cheaper route, go read a bunch of the back articles at The Rocketry Forum or Rocketry Planet (which may not be around long) or the other rocket places on the net (Ye Olde Rocketry Forum is another, I think). For an old reference, pick up the book by Tim Milligan (Apogee, Inc. - he's online).
Then, start building a couple of l
Have you ever said to yourself (Score:2)
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Accuracy and difficulty (Score:2)
UFO (Score:1)
Have you any humorous stories where people mistook your rocket for something else?
A UFO, government spyplane, terrorist weapon, etc?
Have you ever considered building something mischievious deliberately intended to make people think of one of the above?
Spinning (Score:1)
Breaking the 100,000 foot Limit .... (Score:2)
Passive vs active stabilizing (Score:2)
For low-altitude rocketry, passive stabilizing is just fine. When you start getting to the heights your rocket is reaching, it's hard to imagine that this is still the case, yet your diagrams on your website show no active mechanism for keeping the rocket upright, the base fins for stability and that's about it. (Actually, given the wind sheer, it would be almost as bad to be blown horizontally yet remain vertical. To fix that, you'd need full-blown guidance.) To be fair, though, the diagram is hellishly cr
Where is (Score:2)
The frickin laser beam..
Just kidding, really a great piece of work.
My question is:
Did you mix the solid fuel yourself or was that made for you.
Theory vs Practical Experience (Score:2)
Rocket Assists (Score:2)
There are a lot of projects that aim to give rockets an assist at the start. NASA has experimented with ski ramps (and is back to them again) but has also played with turbine-assisted ramjets and variants thereof. ScaledX opted for a hybrid liquid/solid fuel motor, to get the controllability of liquid fuels with the oomph and reduced weight of solid. Have you considered any non-standard design or are you more in the "keep it simple" camp?
controlled airspace? (Score:2)
As for a question, what, if any, notifications, waivers, etc. were required to penetrate controlled airspace in the launch area? At the very least, you would have penetrated Class A airspace (between 18,000MSL and 60,000MSL over the entire contiguous 48 states), so I presume you had to have FAA approval?
next launch? (Score:2)
(Well in fact it's too far away for me, but I'd love to ;-) )
Limits on GPS for Civilian Use (Score:2)
How do you get around the restrictions on civilian GPS. Whilst I'm sure this was taken into account, civilian GPS receivers are limited to speeds quite a bit below the speed achieved, and altitudes of around half of the achieved altitude:
http://en.wikipedia.org/wiki/Global_Positioning_System#Restrictions_on_civilian_use [wikipedia.org]
"The U.S. Government controls the export of some civilian receivers. All GPS receivers capable of functioning above 18 kilometres (11 mi) altitude and 515 metres per second (1,001 kn) are cla
Developing intérêts in rocketry (Score:2)
Thoughts on N-Prize, doable? (Score:1)
Say, Derek, any chance.... (Score:2)
Balancing work, family, and play (Score:2)
In all seriousness, how do you (appropriately) balance work, family, and play time? In looking at your website, you seem to do at least two of those (family + play time) very well.
Potential range (Score:2)
23 miles is a great feat, congratulations!
I'm a layman but having read about the stroke victim in Antarctica I got curious about the application of aerospace technology to emergency transport, rescue, communications, observations, and whether focus on these issues could help attract funding to civilian engineering teams.
For example, it is apparently 5430km from Wellington, NZ to the Amundsen-Scott South Pole Station, and more like 6000km from Australia.
What would it take (team, cost, time, technology) to bu
Education (Score:1)
Temperature/Pressue (Score:1)
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It says "Ask Derek Deville About High-Altitude Amateur Rocketry" not "Troll Derek Deville With Incredibly Stupid Questions"
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by saying: "Do you want to see my rocket? It has a lot of fuel!!"
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You are tragically confused. Marriage and having kids does not get in the way of being a man; quite often, it's part of the path to being a man. You seem to think that having a family means you're henpecked and emasculated, but that's very clearly not true. You're only focusing on the pathological cases, and ignor
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Did your wife make you write that?
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Most everyone I know does this just for the fun of it. You can sometimes get some funding fro universities and even high schools. Students build instrument packages and you fly the package for them. The money they give you will usually cover the cost of the motor and a bit extra but that is about it.
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Is your rocket safe for the environment?
Was the rocket outside the environment when the front fell off?