GMAC Forum

General Category => General Discussion => Topic started by: Jim (Chairman) on 03/04/2015, 01:41:04 PM

Title: RadJet 800 Launch Catapult!
Post by: Jim (Chairman) on 03/04/2015, 01:41:04 PM
Behold the madness!

Inspried by Morgan and a need to have a way of launching a RadJet solo, without chopping all your fingers off.

I give you RadJet 800 Launch Catapult Mark I...

(http://www.eight33n.com/gallery2/d/2142-2/IMG_2664.JPG)

(http://www.eight33n.com/gallery2/d/2146-2/IMG_2667.JPG)

(http://www.eight33n.com/gallery2/d/2149-2/IMG_2668.JPG)

(http://www.eight33n.com/gallery2/d/2152-2/IMG_2669.JPG)

LiPo powered. Arduino ATtiny45 control. Mechanical power from woven nylon shock cord.

Obviously the RadJet would have some throttle set, probably about 50%, as I think 100% will make it launch vertically out of the carrier...

I have a YouTube video of testing also: http://youtu.be/jU2-lAZj8RE (http://youtu.be/jU2-lAZj8RE)

Embrace the madness...
Title: Re: RadJet 800 Launch Catapult!
Post by: Chairman on 09/04/2015, 08:40:20 PM
Wow! is all I can say Jim. Can you make sure someone get's a video when you first try it?

Title: Re: RadJet 800 Launch Catapult!
Post by: Jim (Chairman) on 10/04/2015, 11:32:54 AM
Chris,

Will get field video when I have a new Radjet to test with.

Got 2 controlled flights in over the weekend including reversals.

Control still very twitchy so dial in more expo. Problem was on third flight I basically had no (very little) up elevator so climb out resulted in messy wing-over followed by ground vertically under power.

No problem, Hobbyking have a listing for a Radjet at only £27 in the UK: https://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=31128 (https://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=31128)

I have all the other parts, so it won't take long to have a new one flying again...

Title: Re: RadJet 800 Launch Catapult!
Post by: ANDY MUCKLEY (Safety Officer) on 28/04/2015, 11:22:21 PM
Brilliant Jim just brilliant,