How's this for an air start?

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adrian

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Rocket Launching Quadcopter - Flight Test

The copter looks stable enough as the rocket is launching and the stock Estes deflector plate seems to prevent it from being damaged as the rocket launches. The altitude of the copter is presumably limited by the length of the controller cable.
 
Looks like an Estes Amazon - I wonder if he bought the launch set and has a crossfire to test with too.

I would expect that there is enough battery power on the quadcopter to set the ignitor off remotely - I could be wrong though.
 
I would expect that there is enough battery power on the quadcopter to set the ignitor off remotely - I could be wrong though.
More than enough. They use ultra high current draw capable (low internal resistance) lithium polymer (LiPo) battery packs because that's what the high current brushless motors need.
 
Looks like an Estes Amazon - I wonder if he bought the launch set and has a crossfire to test with too.

I would expect that there is enough battery power on the quadcopter to set the ignitor off remotely - I could be wrong though.

You are correct, there is plenty of battery power available to fire the ingiter. I fly electric RC airplanes and fly at over 1000 watts on 5 and 6 cell powered airplanes.


Rob


Rob
 
Sweet!! So you are still igniting the motor with a standard controller?
 
I would presume in order to comply with the NARMRSC (if anybody cares about that) there would have to be some kind of attitude-sensing system which would disable ignition if the rocket is pointed more than 30 degrees from the vertical.

Just eyeballing from the flight videos it looks like the launch angle was fine in that regard but I dunno if a late gust of wind or something would kick it off kilter.

It looked as if the motor ignition on the blast deflector didn't have any appreciable destabilizing effect on how the quad was flying.
 
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I would presume in order to comply with the NARMRSC (if anybody cares about that) there would have to be some kind of attitude-sensing system which would disable ignition if the rocket is pointed more than 30 degrees from the vertical.

This should be legal to fly.

There is nothing in the safety codes requiring an attitude-sensing system for a launcher on the ground either. Wind has been known to blow over pads, with models on them, sometimes during the count-down. What keeps the rocket from being fired when it is laying on the ground when that happens? The human with eyeballs and a brain knowing not to press the button in that case, no need for an automated system.

One of the things I have done in the past is a twin Rocket Boosted Glider, a winged "mother ship" carrying a scaled up R/C SkyDart on its back. I flew the booster ship by R/C and flipped a switch to air-start (stage) the Skydart right about when the booster ship's engine burned out....with the SkyDart pointed "up" (A second pilot flew the Skydart). No rules required any system to prevent it from being accidentally fired at the wrong angle. And actually the rules would allow that to be fired horizontally, if it was gliding safely at a decent altitude. I never got around to trying that mode though.

The NAR has a safety code for R/C Rocket Boosted Gliders. While it is written for gliders, it does incorporate procedures for radio control airstarts. Only the most stick-in-the-mud RSO would not allow such a thing to fly because the codes do not expressly mention it…but definitely do not forbid it. There's many things that the safety codes do not mention, which have allowed the hobby to grow thru the years.

The following is the most useful part of the R/C RBG code, about air-starts:

https://www.nar.org/NARrcrbgsc.html

"Air-starts. During stable, gliding flight of the R/C RBG, an attached motor may be air-started to increase the model's altitude or airspeed without diving. This is permitted if:
*
a. The onboard R/C ignition system is designed to not to be triggered accidentally, possesses an arm/disarm system, and is not armed until the model is on the pad with the radio system turned on and verified.
b. The proposed airstart was reviewed and approved by the Range Safety Officer (if present) prior to launch.
c. The model heading is not toward spectators.
d. The model is at least 100 feet above the launch site.
e. The pilot gives a loud countdown for the air-start.
If the model descends below the minimum altitude for air-starts or the air-start fails, the model will be landed in a safe area, clear of people, and only the pilot or pilot's appointed helper will be allowed to approach the model until the ignition system has been disarmed".


In that case the issues with air-starting a glider is when the glider is gliding horizontally, and it would not be safe to try to ignite an onboard motor to reboost the glider if it is really low, due to the initial flight path being horizontal before pulling up towards vertical.

If I was an RSO at a launch and someone wanted to fly the kind of multicopter-pad in the video, I'd first ask them to do a test flight, no ignitor, with prepped rocket onboard, at a safe location not near any people or any significant objects. To demonstrate they had built a safe model-system, and were able to fly it safely under good control. I'd also review their arming and firing system with the transmitter. If the test flight went smoothly, then I'd let them fly it and launch the rocket... taking off from and staying near a safe location.

BTW - nearly all of the modern multicopters are using automated stabilization systems to kepe them pointed vertical. The "piloting" is more like the pilot commands the copter to tilt off-vertical a bit to move left-right, or fore-aft, but if they let go of the Tx sticks, to neutral, the copter rights itself automatically. I got to fly one, with no planning in advance because the owner wanted me to fly it with a GoPro onboard to get airborne footage of him flying another plane past it. It was easy to fly, because it was so automated and kept itself vertical except when I commanded it to tilt a little bit (there was about a 5 mph wind, so to keep it from drifting downwind I tilted it enough to fly at about 5 mph into the wind). I have tried flying "conventional" R/C copters, without automatic stabilization in R/C simulators and crash and crash and crash. The stabilization systems use in most multicopters are just incredible (some can even come right back and land where they took off from, all by themselves).

So, a "gust" would likely not be a problem in making the multicopter tilt over. Unless the design had a fatal flaw like the R/C TARDIS, where it was unable to keep itself pointed up after it flew too fast sideways (at too much of a tilt angle) and almost literally "lawn-darted". But the design of the copter-pad in the video seemed very stable, the TARDIS was an extreme.

- George Gassaway
 
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This should be legal to fly.

There is nothing in the safety codes requiring an attitude-sensing system for a launcher on the ground either.

- George Gassaway
Is there anything in the contest reles that specifically states that the rocket must be launched from a ground based launcher? If not, quick, set a bunch of altitude records by flying your launch pad to 400 feet before launching! :)
 
That video was shot out here in the Sonoran Desert. But as far as I know, I don't know who.
 
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