# RC helicopter video **URL:** \ **Category:** Factual Questions\ **Created:** [March 26, 2004, 9:52pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642 "2004-03-26T21:52:38Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![El\_Kabong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/el_kabong/32/496_2.png) [@El\_Kabong](https://boards.straightdope.com/u/El_Kabong)\ **Post date:** [March 27, 2004, 5:36am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/21 "2004-03-27T05:36:31Z")
Yeah, that video’s pretty spectacular. > [@](#): > > But reverse pitch and fly upside down? Maybe an RC chopper can do this. But as I mentioned, the dynamics of flight for a chopper would be so screwed up I doubt it could be done. I’ve seen loops by helis but never extended inverted flight. A fixture at the Paris Air Show during the '90s was a demonstration by an Aerospatiale (now Eurocopter) Panther that featured multiple loops. I witnessed this myself at two different shows. The loops were… strange, as they were far tighter than anything I’d seen done by a fixed-wing aircraft; more like backflips than loops, really. My understanding is that the heli must have a rigid, rather than rocking hub for such maneuvers to be practical. If anyone is interested, here’s some further discussion from the Skunk Works Digest on aerobatic maneuvers, among other things, by helis. [http://www.netwrx1.com/skunk-works/v05.n281](http://www.netwrx1.com/skunk-works/v05.n281) ---
**Author:** ![RotorHead](https://avatars.discourse-cdn.com/v4/letter/r/85e7bf/32.png) [@RotorHead](https://boards.straightdope.com/u/RotorHead)\ **Post date:** [March 27, 2004, 5:36am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/22 "2004-03-27T05:36:53Z")
> [@scr4](#): > > …looked like it was generating lift while at a 45-degree angle. Was it just illusion? How far off from vertical (relative to the chassis) can the net thrust be? Plenty farther than 45 degrees. As long as the vertical component of lift equals or exceeds the load, then the helicopter will not descend. I’ve had helicopters in banks as steep as 75 degrees and maintained level. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [March 27, 2004, 5:54am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/23 "2004-03-27T05:54:36Z")
> [@RotorHead](#): > > Plenty farther than 45 degrees. As long as the vertical component of lift equals or exceeds the load, then the helicopter will not descend. It may not descend but it would zoom off horizontally at 1-G acceleration, wouldn’t it? You can’t actually _hover_. But I guess the heli in the video clip _was_ moving sideways - hard to tell. ---
**Author:** ![RotorHead](https://avatars.discourse-cdn.com/v4/letter/r/85e7bf/32.png) [@RotorHead](https://boards.straightdope.com/u/RotorHead)\ **Post date:** [March 27, 2004, 6:09am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/24 "2004-03-27T06:09:21Z")
Horizontal acceleration is going to be dependent on how much the horizontal component of lift exceeds centrifugal force. But you are right, it won’t be capable of hovering in one spot if the main rotor disc is banked. (eliminating the wind factor). I only viewed the video once, and I was too busy being amazed at the talent that guy has, to spend much time analyzing the flight. There were times that the camera perspective made it difficult to see exactly what position the helo was in. I suspect they didn’t break any laws of physics during the flight though. 😉 ---
**Author:** ![Tokyo\_Mann](https://avatars.discourse-cdn.com/v4/letter/t/e480ec/32.png) [@Tokyo\_Mann](https://boards.straightdope.com/u/Tokyo_Mann)\ **Post date:** [March 27, 2004, 7:27am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/25 "2004-03-27T07:27:39Z")
> [@moriah](#): > > And how does the camera never lose sight of the helicopter no matter how fast it jerks around? If real, the camera operator is as great a virtuoso as the helicopter operator. If you notice, the action is pretty much contained within a given range, and although there are quick movements, they don’t go forever. The camera operator is good, and could well be familiar with the helicopter operator’s moves, but not to take anything away from the camera operator, I don’t think they are comparable. I’m with \*\*Starguard \*\* wondering “how many choppers did he go thru (crash) before he learned to fly like that?” I’ve got a little indoor RC helicopter I just got and just getting it up in the air has cost me a number of rotors. Do they sell this in the States? It’s a little 100 gram RC helicoptor. The site is in japanese, but if you “Windows MediaPlayer” you can see a demo. [http://www.keyence.co.jp/hobby/heli/index.html](http://www.keyence.co.jp/hobby/heli/index.html) ---
**Author:** ![flight](https://avatars.discourse-cdn.com/v4/letter/f/bbce88/32.png) [@flight](https://boards.straightdope.com/u/flight)\ **Post date:** [March 27, 2004, 8:33am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/26 "2004-03-27T08:33:20Z")
> [@RotorHead](#): > > Flying upside down is not entirely uncommon for some military helicopters. There are plenty of videos to be found on that, and you will surely see some of that if you watch the Discovery Wings channel for a while. I would be very interested in seeing anything like this. I am in the last month of my doctorate in aerospace eng. working on helicopters, have friends working at NASA Langley, NASA Ames, Boeing, etc, etc, and have a friend who currently flys Apaches in Kosovo, but I have never heard of a manned helicopter maintaining inverted flight. Sure, loops are fine, but the rotor is still producing positive lift (as noted by the “backflip” comment in earlier posts). If you try inverted flight your base coning angle will be close to chopping off your bloody tail boom. Do you know which helicopters have done this? ---
**Author:** ![flight](https://avatars.discourse-cdn.com/v4/letter/f/bbce88/32.png) [@flight](https://boards.straightdope.com/u/flight)\ **Post date:** [March 27, 2004, 9:11am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/27 "2004-03-27T09:11:22Z")
OK, I have googled this quite a bit, and found nothing, though with all the R/C stuff I had to sort through I might have missed something. Any links about a real helicopter being inverted tend to be like the following: “…the helicopter inverted and crashed, killing the pilot.” “…helicopter’s tail and the main-rotor system sustained catastrophic damage, rendering the helicopter uncontrollable. The helicopter pitched inverted and plunged…” “The helicopter inverted and crashed into the river…” In fact, I couldn’t find anything about a real helicopter flying inverrted without “crash” appearing later in the sentence. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [March 27, 2004, 11:57am UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/28 "2004-03-27T11:57:37Z")
> [@RotorHead](#): > > …Flying upside down is not entirely uncommon for some military helicopters. There are plenty of videos to be found on that, and you will surely see some of that if you watch the Discovery Wings channel for a while… I watch _Discovery Wings_ a lot, and I’ve never seen amy sustained inverted flight on it. Looping and rolling yes, but nott horizontal flight or hovering. I don’t believe it’s possible, but IANA engineer. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [March 27, 2004, 1:41pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/29 "2004-03-27T13:41:09Z")
> [@Tokyo\_Mann](#): > > I’ve got a little indoor RC helicopter I just got and just getting it up in the air has cost me a number of rotors. > Do they sell this in the States? It’s a little 100 gram RC helicoptor. The site is in japanese, but if you “Windows MediaPlayer” you can see a demo. > > [http://www.keyence.co.jp/hobby/heli/index.html](http://www.keyence.co.jp/hobby/heli/index.html) Those little helicopters are just starting to show up in stores and catalogues for order here in the States. ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [March 27, 2004, 2:05pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/30 "2004-03-27T14:05:37Z")
Thanks **flight** and **Boyo Jim** I still don’t believe that helicopters can fly inverted. Loop, sure. Fly upside down for any length of time? Eh, I’m gonna need evidence. I can’t get the video to play, but I sure would like to see this RC stuff. ---
**Author:** ![Mr.Blue\_Sky](https://avatars.discourse-cdn.com/v4/letter/m/d26b3c/32.png) [@Mr.Blue\_Sky](https://boards.straightdope.com/u/Mr.Blue_Sky)\ **Post date:** [March 27, 2004, 2:12pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/31 "2004-03-27T14:12:51Z")
> [@enipla](#): > > Thanks **flight** and **Boyo Jim** > > I still don’t believe that helicopters can fly inverted. Loop, sure. Fly upside down for any length of time? Eh, I’m gonna need evidence. > > I can’t get the video to play, but I sure would like to see this RC stuff. If you can get access to the DIY channel, there’s a show called “Radio Controlled Hobbies”. I’ve seen these helicopters on there and what is shown in the video IS possible. ---
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [March 27, 2004, 2:18pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/32 "2004-03-27T14:18:36Z")
> [@](#): > > If you can get access to the DIY channel, there’s a show called “Radio Controlled Hobbies”. I’ve seen these helicopters on there and what is shown in the video IS possible. Thanks Blue Sky. I may have to order some more channels. And just to clarify, I never said what was done in the video was impossible, heck I haven’t even seen it. I just doubt that ANY full size helicopter can fly inverted. ---
**Author:** ![Mr.Blue\_Sky](https://avatars.discourse-cdn.com/v4/letter/m/d26b3c/32.png) [@Mr.Blue\_Sky](https://boards.straightdope.com/u/Mr.Blue_Sky)\ **Post date:** [March 27, 2004, 2:24pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/33 "2004-03-27T14:24:38Z")
> [@enipla](#): > > Thanks Blue Sky. I may have to order some more channels. > > And just to clarify, I never said what was done in the video was impossible, heck I haven’t even seen it. > > I just doubt that ANY full size helicopter can fly inverted. Sorry, I misunderstood. A real helicopter would likely to torn to shreds. if it even tried to invert. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [March 27, 2004, 6:21pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/34 "2004-03-27T18:21:56Z")
I must say, it looked entirely real to me (and awesome- the chopper looked EXACTLY like a dragonfly in terms of its movement at some points) _except_ the part where is simply hovers upside down an inch above the ground. Watch the rotor blades very carefully- they are revolving only about once a second. At that speed, they can’t be generating much more force than a ceiling fan. ---
**Author:** ![pilot141](https://avatars.discourse-cdn.com/v4/letter/p/e0b2c6/32.png) [@pilot141](https://boards.straightdope.com/u/pilot141)\ **Post date:** [March 27, 2004, 6:38pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/35 "2004-03-27T18:38:10Z")
**RNATB** that’s an illusion created by the “shutter speed” of the camera and the blade rotation speed. Digital video cameras have this problem more than old analog ones. I’ve seen video of airplanes in flight where the prop appeared to be making slow, lazy rotations that could never maintain flight. Someone more familiar with video cameras could explain it better, but it’s really just an illusion. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [March 27, 2004, 7:46pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/36 "2004-03-27T19:46:44Z")
You can see the same apparent slow rotation effect on car wheels, at night under some typrd of artificial lighting conditions, without a camera involved. In that case, the affect is produced by the interaction of “blink rate” of the lighting, flashing in and out of phase with the rotation rate of the wheel. At certain speeds, the wheel (most often the hubcap) appears to be at a dead stop as the car races down the road. It’s commonly called the strobe effect. ---
**Author:** ![GreyWanderer](https://avatars.discourse-cdn.com/v4/letter/g/7cd45c/32.png) [@GreyWanderer](https://boards.straightdope.com/u/GreyWanderer)\ **Post date:** [March 27, 2004, 8:01pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/37 "2004-03-27T20:01:16Z")
The effect can also be seen in racing games, such as F-Zero on the Nintendo 64. The railings at the sides of the road is often a small pattern that repeats. When you reach high speeds the railing will repeat one or more times between each frame. ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [March 27, 2004, 10:26pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/38 "2004-03-27T22:26:47Z")
For the record, the Raptor 60 has a rotor speed that ranges from [1750 to 1850 rpm](http://www.raptortechnique.com/troubleshooting.htm), or 30 rotations per second, and video is capture at 30 frames per second. This accounts for the strobe effect which gives the appearance of one rotation per second. ---
**Author:** ![Sam\_Stone](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@Sam\_Stone](https://boards.straightdope.com/u/Sam_Stone)\ **Post date:** [March 27, 2004, 10:49pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/39 "2004-03-27T22:49:55Z")
> [@](#): > > **Originally Posted by moriah** > And how does the camera never lose sight of the helicopter no matter how fast it jerks around? If real, the camera operator is as great a virtuoso as the helicopter operator. One answer may be post-production. If your video camera has a resolution of, say, 1024 x 768, and you are producing a web video of 320 x 200, then when you are editing the video you can Pan and Scan a 320 x 200 window to keep the helicopter in view at all times. If you saw the raw video, it would look like it was maybe 4x bigger, and the helicopter would be a small dot in the frame. You can use the same technique to get rid of jitter and unsteady camera work. In fact, that’s how electronic image stabilization in video cameras works - the actual number of pixels of the CCD is bigger than the final image, and the camera moves the image window around to compensate for camera shake. The higher the resolution of the original footage, the better job you can do in editing. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 27, 2004, 11:15pm UTC](https://boards.straightdope.com/t/rc-helicopter-video/236642/40 "2004-03-27T23:15:41Z")
I’m almost certain that the video must have been cropped to keep the copter central where possible - in cases where the camera is panning rapidly, there is no overshoot at all when the machine suddenly banks and there’s none of that oscillation that is almost inevitable when tracking a fast moving object. [Previous page](https://boards.straightdope.com/t/rc-helicopter-video/236642.md?page=1) [Next page](https://boards.straightdope.com/t/rc-helicopter-video/236642.md?page=3)