Tag Archives: jet

H29 Jet Flight

The H-29 Pushprop Jet by chara is a small park jet with a mid-mounted motor and taileron configuration. It uses only two servos and three channels. The thrust pushes directly through the tail, being slightly diverted by the elevons; giving this model superb performance similar to other, more complex, thrust-vectoring models. Last time I wrote about this plane I had flown it with a 7×5 APC prop and didn’t like the performance.

So I finally tested two other propellers with the 28-26 1360kv motor. Previously I had chosen a seven-inch propeller because I thought if I went up to the recommended eight-inch it would strike the wood dowels on the twin booms but later noticed there was plenty of clearance, so I got a GWS 8×6 and an APC 8×8 today and went out to test which would give me better performance. On the bench test, the GWS 8×6 seemed to give me much more thrust but I found out otherwise at the field.

APC propellers are built for speed. Once they reach enough RPMs, they produce efficient thrust. GWS propellers, in the other hand, are built for general-purpose and scale flight. They produce max thrust almost immediately but are slightly less efficient at higher RPMs.

Watch the video and enjoy.

Wondering how I shot the video and flew at the same time? Here’s the rig:

Don’t forget to follow me on Twitter @killerwin.

h29_1

H29 Foamie Jet First Trials

I built Chara’s H29 Jet last week. I wanted a fast-to-build, simple, fun jet to fly at the park. I used Elmer’s Foam Board, wood dowels, and Gorilla glue. I knew it would end up heavy, but I wanted the added weight for stability in the wind. I went with an Exceed RC Alpha 370 brushless motor, 1360 kv with a 7×5 prop.

It few well but nowhere as fast as I want. I had the rates set at 100% for high and 50% low but that was way too much. I have to try 50% high and 35% low next time. I read up on people using 8×7 props with this motor so I’ll go with one of those next flight.

http://twitpic.com/44zqyc http://twitpic.com/46kc1q http://twitpic.com/45pma7

Park Jet Sneak Peek

The foamie jet is coming along nicely. I’ve finished gluing the wing and fuselage. The vertical stabilizer is on and all that’s left is to cut the elevons before the electronics and parts arrive. I must say: it looks sexy! I can’t wait to see it in the air.

A bit of sad news: HobbyKing.com has announced a new “V2″ radio system to replace my radio so I think that system is canned. The receivers are out of stock and don’t seem to be coming back in. I think it’s time to invest in some kind of modular radio.

Mach-3 Foamy Build

I’m building the Mach-3 by chara. Its free plans are located in this RCGroups thread.

Tonight I got the 4mm foam from Dollar Tree and cut the pieces out. I glued the cockpit/fuselage together and the horizontal stab/elevator to the vertical stabs.

http://www.maydayrc.com/wp-content/uploads/2010/04/photo-0472.jpg

http://www.maydayrc.com/wp-content/uploads/2010/04/photo-0473.jpg

Things to-do this week or two:

  • Put in 3mm carbon-fiber rods (36 inches x 2) ┬áin main wing, vert stabs, elevator and down length.
  • Hinge all control-surfaces (ailerons and elevator – original version is elevon-mixed; something which I cannot do with my radio)
  • Cut-out canopy for battery access.
  • Glue back-half to front-half of plane.
  • Install servos and linkages
  • Build motor-mount
  • More…

Follow this build at RCG:
http://www.rcgroups.com/forums/showthread.php?t=1230656