RC fighter model UAV build in Jet engine 360+mph [video](youtube.com)
youtube.com
RC fighter model UAV build in Jet engine 360+mph [video]
https://www.youtube.com/watch?v=Uz8SjWnVSBs
16 comments
I also noticed in the video that they had hearing protection but it was on the ground next to the fire extinguisher.
Reading the very nice detailed instruction manual[1]:
[1] http://www.jetcatusa.com/PDFFiles/Instruction%20manual%20V6....
Reading the very nice detailed instruction manual[1]:
To the avoid hearing damage, always use hearing protection when
you are near a running turbine engine!
A flying model with a turbine can reach higher flight speeds
than ducted fan-powered models, because the turbine’s thrust
degrades less with higher flight speeds. With attainable flight
speeds of over 250 MPH, you can quickly run out if flying room.
There is also a danger of developing control surface flutter
or mechanical overload, causing the model to fail in flight.
[1] http://www.jetcatusa.com/PDFFiles/Instruction%20manual%20V6....
If you saw a video of someone flying a full scale aircraft without incident, would you assume by default that they are being irresponsible? I don't think most people would say "that seems irresponsible since it's basically a huge flying missile that could kill dozens of people if it crashed," even if the full scale aircraft was flying in very low visibility conditions.
Someone else posted this further down the thread:
> In the U.S.A. the FAA heavily regulates flying of such aircraft to only approved AMA Academy of Model Aeronautics sites, in where certified turbine pilots may fly. Also, the AMA requires model aviation enthusiasts who wish to operate miniature gas turbine powered RC model aircraft, to be certified in the operation of the type of gas turbine engine, and all aspects of safety in operating such a turbine-powered model aircraft, that they need to know in flying their model.
https://en.wikipedia.org/wiki/Radio-controlled_aircraft#Jets
> In the U.S.A. the FAA heavily regulates flying of such aircraft to only approved AMA Academy of Model Aeronautics sites, in where certified turbine pilots may fly. Also, the AMA requires model aviation enthusiasts who wish to operate miniature gas turbine powered RC model aircraft, to be certified in the operation of the type of gas turbine engine, and all aspects of safety in operating such a turbine-powered model aircraft, that they need to know in flying their model.
https://en.wikipedia.org/wiki/Radio-controlled_aircraft#Jets
'lose' has only one 'o'.
This is an old video; the original is from over five years ago:
http://youtu.be/dTHWBSluUjU
http://www.rcuniverse.com/forum/rc-jets-120/9133201-fast-rc-...
Either it's a rip off or somehow "Jukin Media" got the rights to it... It never ceases to amaze me when old stuff goes viral like this. Maybe it's the keywords stuffed in the title, 'cause UAVs are a pretty hot topic these days, but this thing is not a UAV.
Either it's a rip off or somehow "Jukin Media" got the rights to it... It never ceases to amaze me when old stuff goes viral like this. Maybe it's the keywords stuffed in the title, 'cause UAVs are a pretty hot topic these days, but this thing is not a UAV.
Exactly my thoughts. This video is in my favorites for quite some time and was also surprised how it become "new stuff" without reference to the original upload or other resource.
It is still cool of course, but not UAV,just RC jet ;)
How is this not an unmanned aerial vehicle?
Because UAV has certain connotations in normal parlance. It's like saying that strange plane you haven't seen before is a UFO. A technically accurate but useless description if you want people to understand what you mean.
This appears to be the engine in question:
http://www.jetcatusa.com/p160.html
Executive summary appears to be: 36 lbs of thrust with a (dry?) weight of 3.1 lbs and a fuel consumption of about a pound per minute. Sounds shockingly good, so I have to wonder if the compressor is basically an ablative heat shield and this is good for only a few runs.
That said: doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible. This thing can easily kill someone, wreck a vehicle or puncture a roof if control is lost...
http://www.jetcatusa.com/p160.html
Executive summary appears to be: 36 lbs of thrust with a (dry?) weight of 3.1 lbs and a fuel consumption of about a pound per minute. Sounds shockingly good, so I have to wonder if the compressor is basically an ablative heat shield and this is good for only a few runs.
That said: doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible. This thing can easily kill someone, wreck a vehicle or puncture a roof if control is lost...
Replying at the top here given the conversation down below. Having done RC for many years, been licensed to do it, and having friends that flew helicopters AND jets with a very similar jet turbine in them, I can say with 99.9% confidence that this video was taken at an RC flying field. If this assumption is correct, this has several other assumptions tied to it: a) they are suppose to be there, b) the field is permitted for these types of flights, c) they are certified for these types of flights.
Also, the shot at 4:08 appears to show the runway. The shot at the end where it's landing clearly shows a boundary between longer grass and shorter grass meant for belly landings. We had all of these things at our flying field.
Given the equipment setup, launcher, gauges, fire extinguisher, etc., I'm going with the probability we're dealing with a couple of pros who are capable of conducting this flight in a safe manner at a designated location. You jumping in here making guesses about intent and outcome is a bit shortsighted, and the FUD you are hypothesizing with is simply there to elevate interest in your comment.
Also, the shot at 4:08 appears to show the runway. The shot at the end where it's landing clearly shows a boundary between longer grass and shorter grass meant for belly landings. We had all of these things at our flying field.
Given the equipment setup, launcher, gauges, fire extinguisher, etc., I'm going with the probability we're dealing with a couple of pros who are capable of conducting this flight in a safe manner at a designated location. You jumping in here making guesses about intent and outcome is a bit shortsighted, and the FUD you are hypothesizing with is simply there to elevate interest in your comment.
Sounds like a great reply. Clearly my worry was misinformed. Thanks; for the first two paragraphs anyway.
Y'know, there was a time on HN where making a supposition like that would be met with... an assumption that it was delivered out of genuine concern and not an attempt at "FUD" to "elevate interest" in the comment. Fuck you, basically.
This whole thread makes me sad. Your post is the most informative and valuable, and it's still just ad hominem flaming nonsense.
This site used to be better.
Y'know, there was a time on HN where making a supposition like that would be met with... an assumption that it was delivered out of genuine concern and not an attempt at "FUD" to "elevate interest" in the comment. Fuck you, basically.
This whole thread makes me sad. Your post is the most informative and valuable, and it's still just ad hominem flaming nonsense.
This site used to be better.
I hear you were worried about the setup and safety and I think that's worth considering when you observe things that are new and unfamiliar. I run into it all the time myself: Ebola for example. However, I do think we, as humans, use FUD to project our concerns onto others so they will share the feelings we have. It's an often times necessary habit we must practice in person that doesn't translate well to the Internet. An ad hominem argument is one that attacks a person (or thing) based on a casual connection (or sometimes no connecton/strawman). In a way, make up a story based on the fears is ad hominem because it is only loosely related to the subject matter.
I'm sorry this mad you sad. That was not my intent.
I'm sorry this mad you sad. That was not my intent.
> doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible.
Except you have no reason to think it was in a 'suburban park' other than for the reason you get to judge someone you don't know.
The footage clearly looks like a huge open field with no other people visible or vehicles or roofs around.
Except you have no reason to think it was in a 'suburban park' other than for the reason you get to judge someone you don't know.
The footage clearly looks like a huge open field with no other people visible or vehicles or roofs around.
> Sounds shockingly good, so I have to wonder if the compressor is basically an ablative heat shield and this is good for only a few runs.
The compressor isn't the part of the engine which gets really hot here; that would be the turbine. In these kinds of engines the turbine is typically made out of Inconel, which has no problems handling the ~800C exhaust gas temperature seen at maximum thrust. Preventing the EGT from exceeding a specified limit is the main job of the engine computer, so this is not a common failure mode.
The service interval on Jetcat turbines is 25 hours (some manufacturers specify 50-hour intervals, or even longer), for which the significant portion the work involved is a bearing replacement.
While the thrust-to-weight ratio does seem very good, keep in mind that the quoted weight of 3.1 lbs is likely to not include ancillaries (engine computer, battery and mounting hardware). Also, lubrication is provided by oil mixed in with the fuel rather than a closed-loop oiling system.
A thrust-to-weight ratio of 10:1 is impressive, but not out of line with what you'd expect to see from a full-sized turbojet. On the other hand, the thrust-specific fuel consumption for these engines is much worse than a full-sized engine due to the much lower pressure ratio.
The compressor isn't the part of the engine which gets really hot here; that would be the turbine. In these kinds of engines the turbine is typically made out of Inconel, which has no problems handling the ~800C exhaust gas temperature seen at maximum thrust. Preventing the EGT from exceeding a specified limit is the main job of the engine computer, so this is not a common failure mode.
The service interval on Jetcat turbines is 25 hours (some manufacturers specify 50-hour intervals, or even longer), for which the significant portion the work involved is a bearing replacement.
While the thrust-to-weight ratio does seem very good, keep in mind that the quoted weight of 3.1 lbs is likely to not include ancillaries (engine computer, battery and mounting hardware). Also, lubrication is provided by oil mixed in with the fuel rather than a closed-loop oiling system.
A thrust-to-weight ratio of 10:1 is impressive, but not out of line with what you'd expect to see from a full-sized turbojet. On the other hand, the thrust-specific fuel consumption for these engines is much worse than a full-sized engine due to the much lower pressure ratio.
> doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible.
It look like an R/C air park, actually. I live near the headquarters for two large hobby companies (Hobbico - makers of RealFlight, mentioned elsewhere, and Horizon Hobbies). One of the two (I don't remember which) built a similar air park specifically to provide a location for flying R/C jets.
The R/C club is out flying jets most warm weekend days. See it here: https://www.google.com/maps/@40.0591456,-88.5519564,366m/dat...
It look like an R/C air park, actually. I live near the headquarters for two large hobby companies (Hobbico - makers of RealFlight, mentioned elsewhere, and Horizon Hobbies). One of the two (I don't remember which) built a similar air park specifically to provide a location for flying R/C jets.
The R/C club is out flying jets most warm weekend days. See it here: https://www.google.com/maps/@40.0591456,-88.5519564,366m/dat...
This is where they are flying:
http://mvc-apollo68.nl/ https://goo.gl/maps/hYYQg
That's somewhat uninhabited for The Netherlands.
http://mvc-apollo68.nl/ https://goo.gl/maps/hYYQg
That's somewhat uninhabited for The Netherlands.
This. You can see what appears to be a dedicated dirt runway at 1:27.
>That said: doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible. This thing can easily kill someone, wreck a vehicle or puncture a roof if control is lost...
What makes you think that someone who can:
1: Build this plane
2: Demonstrably fly it very well, with clearly a significant amount of experience in flying RC planes, and probably other high speed RC planes
will overlook all safety precautions and take what is likely the highest powered plane they've flown, where something is comparatively likely to go wrong vs traditional RC planes, and go fly it in their local park with people/houses/etc. around?
What makes you think that someone who can:
1: Build this plane
2: Demonstrably fly it very well, with clearly a significant amount of experience in flying RC planes, and probably other high speed RC planes
will overlook all safety precautions and take what is likely the highest powered plane they've flown, where something is comparatively likely to go wrong vs traditional RC planes, and go fly it in their local park with people/houses/etc. around?
Some people with no experience in or awareness of the RC aircraft hobby seem to be terrified of it. It seems particularly common on HN, for some reason.
> I have to wonder if the compressor is basically an ablative heat shield
As an aerospace engineer, this is cringeworthy. How exactly would this compressor function as a heat shield? Is it experiencing hypersonic intake flow as part of an atmospheric reentry vehicle? Makes no sense.
As an aerospace engineer, this is cringeworthy. How exactly would this compressor function as a heat shield? Is it experiencing hypersonic intake flow as part of an atmospheric reentry vehicle? Makes no sense.
While the misnomer is cringeworthy, I also find it disappointing that you didn't extrapolate that he was wondering if parts of the engine ablate quickly. While the sample size is too small to be conclusive, it suggests that you are prioritizing zinging him over having a discussion.
Could weight be saved in a jet engine by making parts of it ablative? I should think this would play havoc with clearances, so it would only be applicable to parts where the exact dimensions aren't too critical, which I suspect would preclude everything near the compressor and turbine.
Also, ablative heat shielding wouldn't apply to anything not exposed to high heat, so this would only apply to the combustion chamber and everything downstream of that.
EDIT: This makes me curious about the pressures in jet engines. They range from ~pi for early WWII engines (Junkers Jumo 004) to almost 40:1 for modern ones! According to pv=nrt, modern jet engine compressors can get pretty hot, apparently. (Disclaimer, I am not an engineer!)
Could weight be saved in a jet engine by making parts of it ablative? I should think this would play havoc with clearances, so it would only be applicable to parts where the exact dimensions aren't too critical, which I suspect would preclude everything near the compressor and turbine.
Also, ablative heat shielding wouldn't apply to anything not exposed to high heat, so this would only apply to the combustion chamber and everything downstream of that.
EDIT: This makes me curious about the pressures in jet engines. They range from ~pi for early WWII engines (Junkers Jumo 004) to almost 40:1 for modern ones! According to pv=nrt, modern jet engine compressors can get pretty hot, apparently. (Disclaimer, I am not an engineer!)
What's the correct terminology? What do you think the major tradeoff in this cheap (?) engine is?
From the specifications:
Maintenance interval: 25 hours
Pretty amazing and I'd love to see the insides of this engine.
Maintenance interval: 25 hours
Pretty amazing and I'd love to see the insides of this engine.
I believe this, or a very similar, engine is shown in one of the "How it's made" episodes. You can see it on youtube: https://www.youtube.com/watch?v=I3jE-PXV-68
There appears to be a large aircraft hangar in the middle distance, you see it a couple of times as the camera sweeps across. I don't think you get many of those in suburban parks.
It could be. But if it is, you seem to be arguing that flying a 360 mph missile around in the airspace above an active airport is... safe?
I'm shocked at the nerve I seem to have hit here. I'm not trying to take your model rockets away here, but this is not a harmless device. I think many people here lack an intuition of how fast "360 mph" is or the kind of energies that are involved. This is getting into the speeds seen for muzzel velocities of handguns, and that engine weight a hell of a lot more than a bullet.
Dangers like that require more care than just "it looks safe to me". Where are the people guarding the range and warning off intruders? Where is the posted notification of the testing schedule?
I'm shocked at the nerve I seem to have hit here. I'm not trying to take your model rockets away here, but this is not a harmless device. I think many people here lack an intuition of how fast "360 mph" is or the kind of energies that are involved. This is getting into the speeds seen for muzzel velocities of handguns, and that engine weight a hell of a lot more than a bullet.
Dangers like that require more care than just "it looks safe to me". Where are the people guarding the range and warning off intruders? Where is the posted notification of the testing schedule?
First up, why the hell are you asking here? Ask the people in the video.
Second, you don't know that they don't have permission to do stuff at the airport for say an hour because its posted. Your whole argument amounts to fear uncertainty and danger.
> I'm not trying to take your model rockets away here...
But you'll spout off on an unrelated forum about dangers you don't even know are mitigated? Not to be too blunt, but grow up. These are professional rc modelers. They know the dangers better than you do. You don't design a launch system for a jet turbine rc model without keeping safety in mind.
Second, you don't know that they don't have permission to do stuff at the airport for say an hour because its posted. Your whole argument amounts to fear uncertainty and danger.
> I'm not trying to take your model rockets away here...
But you'll spout off on an unrelated forum about dangers you don't even know are mitigated? Not to be too blunt, but grow up. These are professional rc modelers. They know the dangers better than you do. You don't design a launch system for a jet turbine rc model without keeping safety in mind.
I spent some time hanging out at an RC club in rural Connecticut that was co-located with a small airport. If you think they just flew their RC machines willy-nilly, you are dead wrong. There was strict coordination with flight control, and real airplanes would take precedence. Traffic was low enough that this worked out well in practice.
And I did in fact witness a jet-powered RC plane being flown there one weekend, which was quite impressive. At no time was a real airplane in danger of some kind of collision.
The point is, RC clubs like this one do think about this stuff, and they do take appropriate precautions.
And I did in fact witness a jet-powered RC plane being flown there one weekend, which was quite impressive. At no time was a real airplane in danger of some kind of collision.
The point is, RC clubs like this one do think about this stuff, and they do take appropriate precautions.
> This is getting into the speeds seen for muzzel velocities of handguns, and that engine weight a hell of a lot more than a bullet.
No, actually; the average bullet travels at 2,500 feet per second (around 1,700 mph) [1].
Also, the pilot of a member of the Jets of Norway R/C club. These are probably some of the most experienced r/c jet pilots in the world. I'm sure they understand the risks involved better than any of us in this thread.
[1] http://www.mythbusterstheexhibition.com/science-content/dodg...
No, actually; the average bullet travels at 2,500 feet per second (around 1,700 mph) [1].
Also, the pilot of a member of the Jets of Norway R/C club. These are probably some of the most experienced r/c jet pilots in the world. I'm sure they understand the risks involved better than any of us in this thread.
[1] http://www.mythbusterstheexhibition.com/science-content/dodg...
Handguns are far slower than rifles. .45 ACP usually goes about 1000 f/s.
That jet, flying at half the speed of a .45 caliber bullet, weighs at least one hundred times as much. I think that's the point GP was trying to make.
The kinetic energy goes up by the velocity squared but then any damage done by the impact would be a function of the impulse and the cross sectional area of the impact. I certainly wouldn't like to get hit by this, but it is probably less lethal than those rubber rounds they use in crowd control.
edit - Boxer Rocky Marciano's punch was measured at 1028 joules, which is supposedly a greater kinetic energy than an armour piercing bullet. Direct kinetic energy comparisons are not as useful as you might think.
edit - Boxer Rocky Marciano's punch was measured at 1028 joules, which is supposedly a greater kinetic energy than an armour piercing bullet. Direct kinetic energy comparisons are not as useful as you might think.
> I'm not trying to take your model rockets away here, but this is not a harmless device.
You're preaching to the choir. The hobbyists in the video are probably more aware of that than anyone in this thread.
You're preaching to the choir. The hobbyists in the video are probably more aware of that than anyone in this thread.
I think you struck a nerve here because your entire argument is based on an assumption. Do you have any evidence he's endangering other people? Do you know something we don't, like there's a playground passed those trees, or he just pulled up in this public space and launched the jet without permission?
If not, then don't insult someone that appears to be extremely competent with years of experience, and call them irresponsible because you're jumping to conclusions.
If not, then don't insult someone that appears to be extremely competent with years of experience, and call them irresponsible because you're jumping to conclusions.
People fly 360 mph missiles around in the air above active airports all the time. Even more dangerously, they often sit in the missile while doing it. Something should be done.
edit - this looks like there is the edge of an airfield on the other side of some pylons. If it is near an active airfield, or if there is any controlled airspace in the vicinity, then I would be incredibly surprised if air traffic control was not kept informed as per the existing regulations.
edit - this looks like there is the edge of an airfield on the other side of some pylons. If it is near an active airfield, or if there is any controlled airspace in the vicinity, then I would be incredibly surprised if air traffic control was not kept informed as per the existing regulations.
They also look very similar to the engines used by Yves Rossy (aka Jetman) on his wing, although they seem to be a bit bigger and more powerful.
http://www.jetman.com/?page_id=242
> That said: doing this stunt in what looks like a suburban park strikes me as shockingly irresponsible. This thing can easily kill someone, wreck a vehicle or puncture a roof if control is lost...
I'd be more concerned with drunk or texting drivers than a R/C jet engine killing me.
I'd be more concerned with drunk or texting drivers than a R/C jet engine killing me.
I'm more concerned with drunk or texting drivers than getting eaten by a tiger. Does that mean I shouldn't be worried if someone lets a tiger loose in the park?
That depends. The tiger might get hit by a drunk driver, then eat them when they get out of the car, thus reducing your overall level of personal risk.
You prove exactly the point. People get all up in arms over silly things when there are much bigger concerns in the world.
Someone shows a video of a RC jet flying extremely fast and the assumption is this guy is endangering the public and has no regard for safety of others.
Lets just get congress to waste time implementing laws for both fast flying RC planes and another one to make it illegal for your tiger to eat a person.
Someone shows a video of a RC jet flying extremely fast and the assumption is this guy is endangering the public and has no regard for safety of others.
Lets just get congress to waste time implementing laws for both fast flying RC planes and another one to make it illegal for your tiger to eat a person.
What if there's a tiger with a team of professional large animal trainers abiding by all sensible guidelines?
except for letting loose the tiger in the first place.
The hypothetical situation I'm proposing is if the tiger is not let loose, but is being tended to by experienced people.
We should also calculate the risk if the tiger was being flown round the park on a jet powered drone, just to cover all bases.
On a probability basis, sure, bad driving is much more likely to kill you. That doesn't mean that jet RC flying like that isn't shockingly irresponsible.
You assume this person is shockingly irresponsible. Do you have proof? What's on the other side of those trees?
I assume that one does not simply dive into the RC world with a jet turbine. Instead this individual has probably had a lot of practice with slower planes, does not want to injury anyone, and is not doing this in Central Park NY
I assume that one does not simply dive into the RC world with a jet turbine. Instead this individual has probably had a lot of practice with slower planes, does not want to injury anyone, and is not doing this in Central Park NY
Interesting that you think the burden of proof should be on me that flying a couple litres of kerosene around the sky at 370mph is not obviously unsafe.
I have no doubt the pilot is experienced, and that the area in general is clear.
I have no doubt the pilot is experienced, and that the area in general is clear.
He doesn't have any burden of proof, especially not to random people on the internet.
He does have to make sure he flies safely, but that's his concern. Relax and enjoy the show. :-)
He does have to make sure he flies safely, but that's his concern. Relax and enjoy the show. :-)
The burden of proof should be on you, if you want to prove that the flying was irresponsible. That's how that works.
So, the actual argument I made was that just because more people were likely to die from drink driving (probability-wise), it didn't mean flying the RC wasn't shockingly irresponsible.
Note that I didn't agree with the claim that this specific flight was irresponsible, just that the fact that more people might die from drink driving is basically irrelevant.
So no, the burden of proof is not on me.
Note that I didn't agree with the claim that this specific flight was irresponsible, just that the fact that more people might die from drink driving is basically irrelevant.
So no, the burden of proof is not on me.
I carefully noted your original argument. That's why I said that the burden of proof should be on you, if you want to prove that the flying was irresponsible.
The RC jet flying that you see in this video requires an immense amount of knowledge, experience, preparation, and flying skill—far more than to fly a normal electric RC plane or multirotor, or even to drive an automobile. There is nothing I saw in this video that looks remotely irresponsible.
Most irresponsible behavior shown on youtube doesn't affect you personally.
It doesn't look like a suburban park at all.
How do you control that? It goes so fast a fraction of a second mistake could be fatal, and you can't see it half the time.
A good eye sight is several times better than the resolution of the video camera. You need a fast reaction time and good 3d orientation sense. You can train that with simulators & video games.
And, of course, a string of previous versions of this sort of rc plane. Without anything except that footage, I can say with 100% certainty that this is not the first rc plane that pilot has flown. I'd be quite surprised if his list of planes before this one didn't approach or exceed 100... (I'm nowhere near ready to fly something like that, and I could list 30 or 40 models I've built and flown).
I have been toying with the idea of trying to create a small Pulsejet[1] engine and stick it on a UAV frame. It's a very simple design and shouldn't be to hard to make with, i think.
[1]: http://en.wikipedia.org/wiki/Pulsejet
[1]: http://en.wikipedia.org/wiki/Pulsejet
Apparently these work OK: http://hobbyking.com/hobbyking/store/__37414__Hobbyking_Puls...
You should see this stuff. http://aardvark.co.nz/pjet/ Pretty crazy. He got some attention in the news a few years ago with his DIY cruise missile project.
Here's the pilot from the op flying a pulsejet ... sounds like a lawnmower:
http://www.youtube.com/watch?v=AJLWMZHlD90
Interesting discussion, clearly the size and speed crosses the 'scary' threshold. I wouldn't worry too much about that however as the risk is small, people invest a lot of time and effort into building models and that investment means that it is very very painful for them if they crash them. In many ways the modeller has more invested in the outcome than onlookers or the folks in the area.
That said, its an amazing to me this guy can keep his head 'in the plane' which is to say at that speed can fly the plane to its orientation rather than his own. When I've flown model planes there are always times where I'm turning the wrong way because I've mixed up the front back / left right controls given a particular plane attitude and direction. (and yes crashed a couple which made me feel horrible and so I stick to vehicles :-)
Next up I hope someone can build a FPOV version so they can fly it from the "cockpit". That would also make for a great video.
That said, its an amazing to me this guy can keep his head 'in the plane' which is to say at that speed can fly the plane to its orientation rather than his own. When I've flown model planes there are always times where I'm turning the wrong way because I've mixed up the front back / left right controls given a particular plane attitude and direction. (and yes crashed a couple which made me feel horrible and so I stick to vehicles :-)
Next up I hope someone can build a FPOV version so they can fly it from the "cockpit". That would also make for a great video.
> That said, its an amazing to me this guy can keep his head 'in the plane' which is to say at that speed can fly the plane to its orientation rather than his own.
If you think the orientation skills in this video are impressive, you should check out the professional 3D RC helicopter pilots!
https://www.youtube.com/watch?v=KuDptulCpK0#t=37
https://www.youtube.com/watch?v=PptMrBFAO-A#t=28
https://www.youtube.com/watch?v=QDxaJTjCFhE#t=16
If you think the orientation skills in this video are impressive, you should check out the professional 3D RC helicopter pilots!
https://www.youtube.com/watch?v=KuDptulCpK0#t=37
https://www.youtube.com/watch?v=PptMrBFAO-A#t=28
https://www.youtube.com/watch?v=QDxaJTjCFhE#t=16
You got that right. I tried RC heli flying for a little bit. Spent several hours flying in the sim and several more flying the real thing, and could never comfortably do a nose-in hover. Very humbling. These professional RC hell pilots are incredible.
Lag and latency would be an issue
https://www.youtube.com/watch?v=sa-TSNeTK-A
this one goes to 440mph ..
pretty impressive toys. How do you control this thing without FPV?
pretty impressive toys. How do you control this thing without FPV?
Almost as fast as the ones with no engines at all... How's a 498mph glider sound?
http://www.rcgroups.com/forums/showthread.php?t=1609281
With a big hill, the right wind, and an appropriate unpowered glider, it looks like this: https://www.youtube.com/watch?v=KjASRmgQWoo
http://www.rcgroups.com/forums/showthread.php?t=1609281
With a big hill, the right wind, and an appropriate unpowered glider, it looks like this: https://www.youtube.com/watch?v=KjASRmgQWoo
Possibly easier than piloting the real thing. No g-force, total vision, simple controls, and so on. With various fail-safes and controllers, its made much easier
Dont get me wrong, I've tried flying normal RC planes, and Im rubbish at it, it is still hard and skillfull. But, if you spend some time on YouTube looking at what people can do with these things, you'll end up wondering if they are bending physics.
Dont get me wrong, I've tried flying normal RC planes, and Im rubbish at it, it is still hard and skillfull. But, if you spend some time on YouTube looking at what people can do with these things, you'll end up wondering if they are bending physics.
I taught myself to fly RC planes using RealFlight[1] RC model simulator using the same transmitter / controller I used for the RC planes configured with progressive rate controls connected via USB interface.
10 hours on the sim using a high-wing trainer with lots of dihedral[2], learned how to land in a gusty cross wind, then out in to the park with my high-wing high-dihedral trainer. Took off, flew, and landed no problems - the RealFlight trainer was nearly spot on.
I then bought a model F4U Corsair, much different plane to fly, they go where you point them and don't self right or self level like a high-wing high-dihedral aircraft. More RealFlight training and then flew and landed it successfully first go to.
Lots of fun! The parks I had easy access to weren't in suburbia though.
1. http://www.realflight.com/ 2. http://en.wikipedia.org/wiki/Dihedral_(aeronautics)
10 hours on the sim using a high-wing trainer with lots of dihedral[2], learned how to land in a gusty cross wind, then out in to the park with my high-wing high-dihedral trainer. Took off, flew, and landed no problems - the RealFlight trainer was nearly spot on.
I then bought a model F4U Corsair, much different plane to fly, they go where you point them and don't self right or self level like a high-wing high-dihedral aircraft. More RealFlight training and then flew and landed it successfully first go to.
Lots of fun! The parks I had easy access to weren't in suburbia though.
1. http://www.realflight.com/ 2. http://en.wikipedia.org/wiki/Dihedral_(aeronautics)
Hey! Thanks for sharing these!
Anyone into this kind of thing may like to check out FPV racing: https://news.ycombinator.com/item?id=8510680
Not quite as fast, but just as much fun!
Not quite as fast, but just as much fun!
That's a turbine powered RC plane, and, technically, an unmanned aerial vehicle, but it doesn't seem to fly autonomously.
Exactly. It's just a radio-controlled model aircraft, which have been around for a long time.
Also, it's worth pointing out that it's not a model of a fighter jet, and that this video seems to be a repost of one that's been up for five years: https://www.youtube.com/watch?v=dTHWBSluUjU
Also, it's worth pointing out that it's not a model of a fighter jet, and that this video seems to be a repost of one that's been up for five years: https://www.youtube.com/watch?v=dTHWBSluUjU
Wow - just realized how slow most drones are.
Could something that small break the sound barrier?
Could something that small break the sound barrier?
I'm not sure what altitude they are at but they claim to be flying it faster than the sound barrier. Don't see anything to back that up.
Only if it were rocket powered. The aerodynamics simply don't scale well enough for something that small to become supersonic using any currently available small turbine engine.
What part doesn't scale? The only thing I can think of that might be a problem is the boundary layer thickness through the intake/diffuser.
Roughly speaking, the drag is proportional to cross-sectional area, whereas engine thrust required is proportional to mass, which in turn is proportional to volume. So, you end up running into a square-cube law situation: http://en.wikipedia.org/wiki/Square-cube_law
Also, the Reynolds number will be completely different for a model aircraft compared to a full-sized aircraft, so they will behave quite differently aerodynamically.
It's also worth pointing out that even the fastest full-size jet aircraft can only just break the sound barrier at sea level (the F-111 did Mach 1.2 at sea level) – going supersonic typically requires flying at a high altitude, which obviously isn't practical or legal for a radio-controlled model aircraft.
Also, the Reynolds number will be completely different for a model aircraft compared to a full-sized aircraft, so they will behave quite differently aerodynamically.
It's also worth pointing out that even the fastest full-size jet aircraft can only just break the sound barrier at sea level (the F-111 did Mach 1.2 at sea level) – going supersonic typically requires flying at a high altitude, which obviously isn't practical or legal for a radio-controlled model aircraft.
>Also, the Reynolds number will be completely different for a model aircraft compared to a full-sized aircraft, so they will behave quite differently aerodynamically.
For low speeds, maybe. For high speeds, you're well into the high Reynolds number turbulent regime. I've worked on R/C aircraft designs and I'm reasonably sure we got decent results with inviscid aerodynamics. At sea level, you're going to see Re in the millions.
Regarding the Square-Cube law, I'm not sure it's that relevant here. It's pretty clear you could put two of those engines in a AMA sized model, so not exceeding 55 lbf. That'd give you a thrust-to-weight ratio of greater than 1.0.
For low speeds, maybe. For high speeds, you're well into the high Reynolds number turbulent regime. I've worked on R/C aircraft designs and I'm reasonably sure we got decent results with inviscid aerodynamics. At sea level, you're going to see Re in the millions.
Regarding the Square-Cube law, I'm not sure it's that relevant here. It's pretty clear you could put two of those engines in a AMA sized model, so not exceeding 55 lbf. That'd give you a thrust-to-weight ratio of greater than 1.0.
> Regarding the Square-Cube law, I'm not sure it's that relevant here. It's pretty clear you could put two of those engines in a AMA sized model, so not exceeding 55 lbf. That'd give you a thrust-to-weight ratio of greater than 1.0.
Yes, a small turbine-powered RC aircraft can easily have a higher thrust-to-weight ratio than a full-sized aircraft, but it's not thrust-to-weight ratio that determines top speed; it's thrust-to-drag ratio.
This is where the square-cube law comes into it. If we take a full-sized delta-winged high performance aircraft like the Eurofighter Typhoon, we could very roughly approximate the difference in drag between that and the model to be proportional to the difference between the square of their wingspans.
I'm guessing the aircraft in the video has a wingspan of 1 m, and the Typhoon has a wingspan of 11 m, so the drag should be greater by something like a factor of 121.
However, the Typhoon's engines provide a combined 180 kN of thrust, which is greater than the 160 N thrust of the Jetcat P160 by a factor of 1125.
So, you can see that the thrust-to-drag ratio of a full-sized jet fighter is something like an order of magnitude larger than for a model aircraft like this, which is the main reason why model aircraft are unable to attain supersonic speeds.
Of course, supersonic flight for model aircraft would pose all the same problems it poses for full-sized aircraft; onset of compressibility affecting control surface response, engine inlet geometry and so on.
Yes, a small turbine-powered RC aircraft can easily have a higher thrust-to-weight ratio than a full-sized aircraft, but it's not thrust-to-weight ratio that determines top speed; it's thrust-to-drag ratio.
This is where the square-cube law comes into it. If we take a full-sized delta-winged high performance aircraft like the Eurofighter Typhoon, we could very roughly approximate the difference in drag between that and the model to be proportional to the difference between the square of their wingspans.
I'm guessing the aircraft in the video has a wingspan of 1 m, and the Typhoon has a wingspan of 11 m, so the drag should be greater by something like a factor of 121.
However, the Typhoon's engines provide a combined 180 kN of thrust, which is greater than the 160 N thrust of the Jetcat P160 by a factor of 1125.
So, you can see that the thrust-to-drag ratio of a full-sized jet fighter is something like an order of magnitude larger than for a model aircraft like this, which is the main reason why model aircraft are unable to attain supersonic speeds.
Of course, supersonic flight for model aircraft would pose all the same problems it poses for full-sized aircraft; onset of compressibility affecting control surface response, engine inlet geometry and so on.
>Yes, a small turbine-powered RC aircraft can easily have a higher thrust-to-weight ratio than a full-sized aircraft, but it's not thrust-to-weight ratio that determines top speed; it's thrust-to-drag ratio.
And parasitic drag dominates, right? Ok, so yeah, I was thinking in terms of induced drag. Thanks for the discussion. I enjoyed it and it was a good refresher.
And parasitic drag dominates, right? Ok, so yeah, I was thinking in terms of induced drag. Thanks for the discussion. I enjoyed it and it was a good refresher.
> Could something that small break the sound barrier?
Why not? Missiles and rockets of similar size do.
Why not? Missiles and rockets of similar size do.
I'M
Another one with 4 jet engine and onboard camera:
http://www.youtube.com/watch?v=ZeL3LhrmeME
Amazing, would love to see this advance to have a camera capable of relaying a camera feed to an Oculus Rift.
The engine is http://www.jetcatusa.com/p160.html. Only costs $4200, which is not too far out there in comparison to quad/hexa/octo setups.
Super cool, and I can't imagine how you could fly this. This is going to scare the hell out of the FAA and Homeland Security. I expect the FBI will start paying the turbine company a visit.
These have been around for many years. The FAA already regulates them.
http://en.wikipedia.org/wiki/Radio-controlled_aircraft#Jets
> In the U.S.A. the FAA heavily regulates flying of such aircraft to only approved AMA Academy of Model Aeronautics sites, in where certified turbine pilots may fly. Also, the AMA requires model aviation enthusiasts who wish to operate miniature gas turbine powered RC model aircraft, to be certified in the operation of the type of gas turbine engine, and all aspects of safety in operating such a turbine-powered model aircraft, that they need to know in flying their model.
http://en.wikipedia.org/wiki/Radio-controlled_aircraft#Jets
> In the U.S.A. the FAA heavily regulates flying of such aircraft to only approved AMA Academy of Model Aeronautics sites, in where certified turbine pilots may fly. Also, the AMA requires model aviation enthusiasts who wish to operate miniature gas turbine powered RC model aircraft, to be certified in the operation of the type of gas turbine engine, and all aspects of safety in operating such a turbine-powered model aircraft, that they need to know in flying their model.
that's old
I still wonder what are the best tech available to have a camera/screen on this thing, with what latency.
I still wonder what are the best tech available to have a camera/screen on this thing, with what latency.
So far as I can tell _nobody_ flies FPV (first person view) with anything except regular analog video cameras and radios.
I'm guessing that's at least partly for cost reasons, but mainly because you don't even need to ask the "what latency" question. Even though iPads/cellphones/OcculusRift have much better and higher resolution screens than most of the inexpensive hobby FPV gear around, the lag as you digitise/compress/decode real time video streams is both too long and too variable.
Remember John Carmak's rant about being able to get packets to London quicker than he can get them onto his screen? Imagine trying to control a ~400mph toy plane when you aren't sure if you've got 15 or 200ms of latency at any time? That'd represent "seeing where you are" something between ~10 and 200 feet behind where the plane is right now.
I'm guessing that's at least partly for cost reasons, but mainly because you don't even need to ask the "what latency" question. Even though iPads/cellphones/OcculusRift have much better and higher resolution screens than most of the inexpensive hobby FPV gear around, the lag as you digitise/compress/decode real time video streams is both too long and too variable.
Remember John Carmak's rant about being able to get packets to London quicker than he can get them onto his screen? Imagine trying to control a ~400mph toy plane when you aren't sure if you've got 15 or 200ms of latency at any time? That'd represent "seeing where you are" something between ~10 and 200 feet behind where the plane is right now.
Thanks for referencing the John Carmak "rant". I missed this.
anyone else interested.
http://superuser.com/questions/419070/transatlantic-ping-fas...
aren't there uncompressed low latency solutions ?
we need more women in the uav industry.
good careers to be had here.
good careers to be had here.
I wonder how this thing handles loosing contact with the controller?
It's no wonder the FCC in US is getting less and less RC friendly, besides the typical "home land security" drama stuff like this in a public park could be a real problem from noise pollution to safety of other people in the area.
All this said, must be quite a rush to play with something like that, I would love to fly it in an open field deep in the desert with a clear open sky.