These changes seemed to have pushed the team’s drone further, as it achieved 393 mph (633 kph or 341 kts) in its first test run. Unfortunately, physics got the better of them, as antenna geometry, the Doppler effect, and signal overload caused the drone to lose connection from the controller at such a high speed. The two did not bother attempting to recover it, as they knew that it was lost for good at these speeds. Furthermore, even if the drone lost connection right in front of the controller, it would have traveled miles at its current speed before it would have crashed.
Thankfully, they still had another drone available for testing and another set of their updated propellers. So, they set out again the following day and continued their tests. It seemed that they only had enough batteries for two test runs, and adverse weather was quickly approaching, so they had to set up quickly and get to flying. It was also a windy day, so they made one downwind flight and one upwind flight, and they just averaged the speeds between the two to get a rather fair result.
It was on the downwind test flight that they achieved their record 453 mph, which is above the 441-mph record that they initially hoped for. However, when they accounted for the 34-mph tailwind, this meant that the drone only had an actual airspeed of 419 mph (674 kph or 364 kts). For their final test run, the duo achieved 397 mph (640 kph or 345 kts) against the wind. They averaged the two runs, getting a figure of 425 mph (685 kph or 369 kts) — this might be a bit short of the more than 434 mph (700 kph or 377 kts) they hoped to achieve, but it still beats the current world record.
If you want to make your own attempt at achieving the drone world speed record, you can actually get guidance through their Drone Pro Hub website. And while they use custom propeller blades made by a professional, you can actually 3D print the body and other components at home with one of the best 3D printers you can buy.
(Score: 5, Touché) by PiMuNu on Monday June 01, @02:30PM (3 children)
> the Doppler effect
speed of light is 3e8 metres per second. The drone was travelling at 2e2 metres per second. So the Doppler shift is about 1e-6. I am skeptical that a radio receiver is sensitive to that.
> The two did not bother attempting to recover it
That's just littering.
(Score: 3, Touché) by Username on Monday June 01, @04:47PM (2 children)
>> The two did not bother attempting to recover it
>That's just littering.
Yeah, if it really is a drone it should fly back or land itself. Who just fires and forgets an aircraft going 400mph?
(Score: 3, Touché) by Unixnut on Monday June 01, @08:56PM (1 child)
Agreed, anything traveling at 453MPH probably has enough kinetic energy to leave a (small) crater and/or cause serious damage if it hits something. After all they are approaching the speed of a cruise missile.
Seems very imprudent to me to fire something off like that then just let carry on flying at speed and out of control until it impacts something.
(Score: 2) by Freeman on Tuesday June 02, @02:45PM
It seems like they're testing it on a large piece of private land. At least that's what I intuited from having watched the video. Certainly letting something go cruising at 400mph+ with no regard for what it could run into would be a problem. However, they seem to be testing it on a rather empty tract of land. I doubt it left any sort of "crater" per se. They were quickly ripping out the essentially dead battery pack on the last run. As it was overheated and they didn't want the whole thing to go up in flames. I'm going to be giving them the benefit of the doubt on this one. It certainly would be ill-advised to be testing something like this anywhere that it could cause damage to a random passerby.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 3, Informative) by VLM on Monday June 01, @03:33PM (3 children)
Its not a "drone" its a radio controlled airplane.
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-107 [ecfr.gov]
107.51 Operating limitations for small unmanned aircraft.
"The groundspeed of the small unmanned aircraft may not exceed 87 knots (100 miles per hour)."
What they did is a felony in the USA although the FAA essentially never enforces RC airplane laws so they'll probably be OK.
My main annoyance is calling a perfectly normal "radio controlled airplane" a "drone" as if its something new and not something the WWII generation was playing with in the 60s. I was similarly annoyed a decade or two ago when "servo" magazine tried to redefine the word "robot" to mean radio controlled car with weapons attached. Pretty lame of them...
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-91/subpart-B/subject-group-ECFRe4c59b5f5506932/section-91.117 [ecfr.gov]
Also as per above the FAA gets really butthurt when people fly below flight level 100 above 250 knots. Low altitude is supposed to be slow enough for pilots and ATC to land and vector around things, so flooring it at low altitude is quite illegal. Part (d) of the regulation above is the military aircraft training work-around it would be illegal to buzz around for the sheer hell of it but for legit military training purposes the FAA doesn't really care. Although famously they will want to post NOTAMs about avoiding training areas, and the FAA will punish private pilots for not knowing a NOTAM was posted after they took off, which is a long standing sore spot. Basically if the FAA is pissed off at you they will find a way to "get" you.
(Score: 3, Informative) by JoeMerchant on Monday June 01, @03:44PM
It's really a promo for the 3D printer company, they sponsor cool projects like this one as low cost advertising.
🌻🌻🌻🌻 [google.com]
(Score: 2, Interesting) by JoeMerchant on Monday June 01, @03:57PM (1 child)
> calling a perfectly normal "radio controlled airplane" a "drone" as if its something new and not something the WWII generation was playing with in the 60s.
The whole term "drone" is pretty muddied in common usage. On the one hand, here on her 100th birthday we're getting recycled pictures of Marilyn Monroe assembling drones for WWII - and that's accurately what they were called, being small unmanned aircraft.
When quadcopters (and similar gyro-feedback stabilized multi-rotor aircraft) came out, everyone called them drones regardless of how much human was in the loop piloting them or not. It's less scary than calling them cruise missiles, though they can also function as those...
Small fixed wing self-piloting drones had a hard time getting recognized as drones with their single props and lifting wings, even though that's the configuration Marilyn is assembling in the old photos.
The 700kph condenders go for the multi-rotor layout, but their aerodynamics more resemble an artillery shell than a traditional hovering quadcopter or lifting wing RC/self piloting craft.
As for FAA involvement, (15 years ago) the first key seemed to be getting permission from the land owner/administrator and otherwise staying "under the radar" - although we rented an airfield one day and 5 minutes after taking off we got buzzed by a crop duster flying below our RC aircraft's altitude of about 120' AGL, the trees were about 50-60' tall - you could see his head snap around eyes locked on our plane as he passed. In a collision our battery is about the only thing that would matter to a plexiglass canopy at 200 knots closure, and hopefully that would bounce up and over - or, if the 2lb nearly fully charged LiPo got chopped by the prop that could be dramatic - the rest of the plane was mostly foam, circuit boards and little servos.
🌻🌻🌻🌻 [google.com]
(Score: 3, Informative) by VLM on Monday June 01, @04:52PM
https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F/part-91/subpart-B/subject-group-ECFRe4c59b5f5506932/section-91.119 [ecfr.gov]
Yeah crop dusters are the intersection of problems see 91.119 above at least in the USA.
Where I live the local RC airplane club is naturally out in farmville because the land is cheap. Which is where the crop dusters like to fly. They also have a really nice elaborate outdoor RC car track, again, land is cheap...
According to the FAA, human airplanes shouldn't fly below 500 feet AGL unless they have an unavoidably good reason, like takeoffs, landings... crop dusting... meanwhile radio controlled airplanes, again according to the FAA, should never be above 400 feet AGL or horizontally anywhere near an airport. So in theory there's never any conflict but IRL its an issue.
When I did ground school and met a lot of pilots, they seem much chiller about RC aircraft than the general public is. Probably a lifetime of the ATIS report always containing "birds in the vicinity of the airport" as a risk makes them ignore the risk; some dude flying a drone 10 miles from the airport is much more boring than the runway is covered with migrating Canadian geese, as happens every year. Very few pilots I met "know a guy" who hit a RC airplane but seemingly everyone "knows a guy who knows a guy" who hit a goose back in the day.
Geese, and birds in general, will do stupid things like land in front of vehicles, not just planes but also cars. Not all impacts are like "500 MPH explosive collisions" the goose ends up just as dead and maybe slightly damage the plane at only 20 mph. No one is going to ground loop a plane full of gasoline into a rain ditch because a goose lands in front of them, so they get whacked sometimes.
(Score: 4, Touché) by DadaDoofy on Monday June 01, @06:11PM
"antenna geometry, the Doppler effect, and signal overload caused the drone to lose connection from the controller"
So they just packed up and left, letting the pieces fall wherever they may? I hate to state the obvious, but you could put an eye out...