PDA

View Full Version : V-1 Buzzbomb



burkefj
4th October 2011, 10:46 PM
I started a thread on rcgroups to show the progress on my V-1. I did a profile version that used an electric tractor in the pulsejet pod. However it was pretty large and that didn't lend itself to rocket boost.

So, I am doing a smaller version that fits onto a standard depron sheet, uses a cruciform structure like my X-15 and A4B.



I'm using a centerline motor setup, so had to modify tail somewhat to allow for some support for the motor mount, and moved the wings back slightly to allow an easier flight CG to be achieved.

Eric1
4th October 2011, 11:20 PM
Kewl!

Eric

burkefj
9th October 2011, 02:37 AM
Test flights were perfect, first test flight needed about 15 clicks of uptrim for post boost glide, second flight linked here, I programmed that into the flap switch so at appogee I just hit the switch and it goes from neutral trim to glide trim, very controllable, even with a good wind, boost was nice and easy, glide was not bad even in the wind.

Frank

burkefj
2nd October 2013, 11:33 PM
I updated the original design to keep the wing a single piece with the fuse, use only one spar, and use taileron controls only and it managed to save 1oz total from the design. Boost even in wind was very straight and very docile...roll control with the tailerons was very good. It's very simple, just a motor tube, two pieces of 1/8" carbon tube, a few 1/8" carbon flats, 5 6mm depron pieces. Two servos. i also switched to rail buttons.


The plans are now posted here: http://www.rcgroups.com/forums/showthread.php?t=979395#post11284823

Here is a video from this afternoons maiden flight, it's small but you get the idea.

http://youtu.be/AuRkoOghAwY

scsager
3rd October 2013, 12:02 AM
Frank - really enjoyed your article in Sport Rocketry.
That was a neat video - Long boost on that motor, one of the AT RC reloads I suspect. What kind of total flight time are you getting?

burkefj
3rd October 2013, 12:44 AM
Hi, thank you. The construction of this is very similar to the winged V-2 or the X-15....the reload is an aerotech E-6 with a burntime of around 7 seconds. It takes a special casing with a closure only on one end. Since these are flat plate wings and are meant to look more like real airplanes than to be efficient gliders, I only get around 45-75 second glide times normally depending on boost/wind/weight. They typically weight in the 8-12 oz realm. It's more just for fun than for long flight, and to be docile on boost/glide. I haven't tried using a true airfoiled wing on them because I was too lazy.


Frank - really enjoyed your article in Sport Rocketry.
That was a neat video - Long boost on that motor, one of the AT RC reloads I suspect. What kind of total flight time are you getting?

K'Tesh
3rd October 2013, 02:15 AM
Nice video...


http://www.youtube.com/watch?v=AuRkoOghAwY&feature=youtu.be


Looks like it was taken somewhere in the Willamette (pronounced "Will Am Met" for those of you who don't live on the Left coast) Valley.

burkefj
3rd October 2013, 03:54 AM
Yup, that's the fly-a-ways field, just south of highway 26 near North plains and the glider port. I did some demo flights for them and showed them the NAR/AMA rules and they gave me the ok to join. It's a nice field, quite open, with a nice conveyor belt matting runway and pit area, you just need to watch your altitude and airspace on wed/saturday when the full size gliders are flying, they make their downwind leg over the field.

Frank



Nice video...


Looks like it was taken somewhere in the Willamette (pronounced "Will Am Met" for those of you who don't live on the Left coast) Valley.

powderburner
3rd October 2013, 07:11 AM
I can't tell from the still pix or the video, but does your glider retain the motor case after burnout or do you eject it? And if it is kept onboard, was there any particular reason you chose to do it that way? (because it's heavier, and hurts your glide performance)

I am not sure that you need to worry about your airfoil being a flat plate for this. At the Rn range for your gliding flight, a flat plate probably works as well as a fancy airfoil would. I am more impressed that on a wing design like the V-1 (a relatively high AR) that your depron wing does not flutter and bend out of shape----pretty cool that it works!

Questn: for this class of rocket boosted gliders, I am curious if you have ever considered using rocketry-type body tube materials and the hollow-shell plastic nose cones to build a more realistic looking fuselage. This would also provide volume for a clean internal installation of servos and other gear. Whaddya think?

burkefj
3rd October 2013, 07:48 AM
Hi, the motor is retained in the rear, with a rear mounted motor, if you eject it you are making an already nose heavy glider even more so. I didn't want to chase two things around so chose not to eject a pod etc, and it makes the construction easier.

As for the fuse, cardboard tubes are much heavier than depron, I've built a Mach 10 upscale with cardboard bt101 and with rolled 3mm depron and the depron version was one ounce lighter. For many of these gliders, the reason they glide so slowly is that the fuse area of the cross section is doubling or tripling my lifting area, if you put a full fuse you loose much of the fuse flat plate lift. I have done full fuse when it was appropriate, a shuttle, buran or ALCM as below. For things will small wings, X-3, X-15 I like to get as much lifting surface as I can. You don't really notice the 2-dimensional aspect when it is in the air.




I can't tell from the still pix or the video, but does your glider retain the motor case after burnout or do you eject it? And if it is kept onboard, was there any particular reason you chose to do it that way? (because it's heavier, and hurts your glide performance)

I am not sure that you need to worry about your airfoil being a flat plate for this. At the Rn range for your gliding flight, a flat plate probably works as well as a fancy airfoil would. I am more impressed that on a wing design like the V-1 (a relatively high AR) that your depron wing does not flutter and bend out of shape----pretty cool that it works!

Questn: for this class of rocket boosted gliders, I am curious if you have ever considered using rocketry-type body tube materials and the hollow-shell plastic nose cones to build a more realistic looking fuselage. This would also provide volume for a clean internal installation of servos and other gear. Whaddya think?

iter
4th October 2013, 05:30 AM
Very nice work as usual, Frank! I like how your builds--and your flights--are drama free. As FAR might put it, "with the successful outcome of a procedure or a maneuver never seriously in doubt."

Thank you for sharing your work with us.

Ari.

burkefj
4th October 2013, 03:29 PM
Thank you, I really appreciate that. My drama filled flights are much less often than I probably deserve:)


Very nice work as usual, Frank! I like how your builds--and your flights--are drama free. As FAR might put it, "with the successful outcome of a procedure or a maneuver never seriously in doubt."

Thank you for sharing your work with us.

Ari.