water powered lifting body rocket glider

Pat contacted me after looking at my web site and eyeball scaling one of my lifting body profiles from the dimensions and applying it to use coroplast corrugated plastic sheet and a water rocket, he has timer that flips the elevons up, one about 1/8" and the other about 1/4". For a second flight, it looks pretty neat, I like his pilot as well. You scan see the screw stops for the elevons, I've asked him for more details on his timer/release mechansim. He said this was at 100psi.


[video=youtube;-9bbWu57oCU]https://www.youtube.com/watch?v=-9bbWu57oCU[/video]

Very cool. If it's typical water rocket stuff, it might be a mechanical "Tomy' timer. Or it could be one of the next gen electronic servo timers. It would be interesting to know.

I confirmed it is a tomy timer...I don't know anything about them.

What, the Major is too important to risk a test flight? Sgt. Storm gets all the hazardous duty.

burkefj said:

I confirmed it is a tomy timer...I don't know anything about them.

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I would have thought you might have heard of them as the one commercial source makes them for RC hobbyists. Not that they are common these days (?) but at least historical. These are better units that the typical ones that I have heard about. The ones commonly used by water rocket folks come from little wind-up toys. Some work better than others. You take it out of the toy, modify the shaft to accept a wire pull pin, and mount it to your rocket. You mount a rubber band with a twine leader to a pull pin that, when taut, holds your chute bay closed (in this case the elevons down). Insert the peg and twist the timer, the number of twists controls your timing. You jam the timer with another pin, oriented to it can pull out when the rocket is launched. It winds down and when the pull pin on the timer shaft is free, it lets the rubber band loose. Whew, simple and low tech, but harder to explain.

US Water rockets and AirCommand have electronic timers that drive small servos to release a band. These (IIRC) include a barometric sensor vs. a simple timer.

Super cool. Thank you for posting these, Frank.

[video]https://youtube.com/watch?v=rWMJAoXus6U[/video]
More flights after trimming

I noticed that he has a video showing his timer setup.

Jim Johnson pinged me the other day after seeing my kits online, he wanted to do a water rocket glider based on my Ikarus kit. I helped him with dimensions and CG calculations and some construction ideas. Here is his result, about 15 ounces rtf, using 90psi presurization test(not sure what he will launch at), this is RC, uses 3mm coroplast for the wings. He just completed glide tests. Arund 22" wingspan and 40" length.

I'd love to see a vid of this.


Richard

Very cool.

Here are some pictures from Jim's first flights, he's getting about 160' with a 15 degree launch angle, he can't put in much boost trim because the boost/thrust phase of the water rocket is so fast and he's still working on transitioning to glide before putting in glide trim, in this flight he pitches on his back and just completes the loop before glide instead of pushing over, but pics are good and it's neat to see the water droplets from the rear and the X on the runway.

This is really cool! I amazed that it can be done. I would think that weight and power would be a major issue. It looks like the altitude is not very high.

Any info on the launcher and the pressure he used?

I believe he quoted 90 to 100 psi, fuel is spent in something like .3 seconds, he is getting 160-200 feet altitude, weight is around 13 oz glide weight.

rstaff3 said:

Any info on the launcher and the pressure he used?

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Brilliant! :wink: