Thread Tools
Apr 21, 2010, 11:39 AM
crash rc plane is my job....
bobby67's Avatar
Sorry Tracytown,

is it your center of gravity the same of the manual (90mm from leading edge) ?

Thanks
Sign up now
to remove ads between posts
Apr 27, 2010, 12:47 PM
It's electric Boogie woogie
bstussie's Avatar
anyone tried the fan jet launcher on some of the larger 90mm EDF's like the FlyFly F4 for example?
Apr 27, 2010, 02:13 PM
Registered User
Doug Bateman's Avatar
I have lauched a 9 lb Savex L-39 from a pvc constructed home made ramp. I only used about 24 lbs pull and never had a problem. I have a Dwg. of the design if needed. No mechanics involved and very economical.
Apr 27, 2010, 02:17 PM
It's electric Boogie woogie
bstussie's Avatar
Quote:
Originally Posted by Doug Bateman
I have lauched a 9 lb Savex L-39 from a pvc constructed home made ramp. I only used about 24 lbs pull and never had a problem. I have a Dwg. of the design if needed. No mechanics involved and very economical.
that would be great, can you post it here or should I just PM you my email?

where are some places to purchase the actual "bungee" material?
Apr 27, 2010, 02:42 PM
Registered User
Doug Bateman's Avatar
Quote:
Originally Posted by bstussie
that would be great, can you post it here or should I just PM you my email?

where are some places to purchase the actual "bungee" material?
Here is sketch. I had a write up about the bungee, the fasteners, the procedure etc. Let me see if i can find it. It was all on a bungee thread here somewhere. I used 1/2" dia. surgical tubing from "Reef Scuba" 1/8" thick wall by 30 ' long.
Apr 27, 2010, 05:36 PM
Big gov never Works
St. Martin's Avatar
Quote:
Originally Posted by bstussie
that would be great, can you post it here or should I just PM you my email?

where are some places to purchase the actual "bungee" material?
http://aerofoam.com/
May 08, 2010, 07:50 AM
Registered User
Thread OP
Quote:
Originally Posted by bobby67
Sorry Tracytown,

is it your center of gravity the same of the manual (90mm from leading edge) ?

Thanks
Yes, it's between 80mm-90mm
May 09, 2010, 09:54 AM
Registered User
SRush99's Avatar
My friend and I are building a launch frame like Doug Bateman's design. For the bungee line, do any of you attach a rag or chute to create drag so that the ring and jet seperate easily? A guy at out field uses one but I'm not sure it's needed.

-Stuart
May 12, 2010, 10:52 PM
AMA 884978/KK6NKY
hillbille's Avatar
Quote:
Originally Posted by Doug Bateman
Here is sketch. I had a write up about the bungee, the fasteners, the procedure etc. Let me see if i can find it. It was all on a bungee thread here somewhere. I used 1/2" dia. surgical tubing from "Reef Scuba" 1/8" thick wall by 30 ' long.
Using your plans I went to Home Depot and got all the parts necessary and built myself a launcher. Tested it today and it works excellently!! I'm a happy camper now!! Thanks a ton buddy!!


Hillbille
May 13, 2010, 02:43 AM
Registered User
STEVEAIR2's Avatar
Hi Doug
Nice launcher I built something very simular my self with one or two differences.
I covered mine with insulation so it does not mark the model.
Also my bungee is more of a commercial unit.I would advise rather than use a straight stake for the bungee cord mount you can get a stake that is metal and is corkscrew shaped.You can get them in pet shops as they are meant for dog leads. You screw them into the ground and tie you dog to it.
There was an incident in the UK where a guy was killed when the Bungee stake pulled out of the ground when the Bungee was loaded and hit him.
Cheers
Steve
May 13, 2010, 03:46 AM
My project: FAIREY DELTA 1
Erik v. Schaik's Avatar
I am willing to sell my ramp. 100USD.
Exellent design. Took me a week to construct.
My new OEM facility in china is near ready for production. This prototype may differ to the new production version. The proto version is well tested and revised. Estimated price will be approx 90USD ex S+H for the final version.
Send me a Pm for additional inquiries.

Best regards,
Erik
May 13, 2010, 06:01 AM
Registered User
STEVEAIR2's Avatar
Hi Erik
Great design
I am surprised you managed to get it finish in a week.It looks like it could have taken longer.LOL
cheers
Steve
Last edited by STEVEAIR2; May 13, 2010 at 03:52 PM.
May 13, 2010, 06:50 AM
Registered User
Doug Bateman's Avatar
Yes, i thought about the corkscrew type, but we had good success with the stake, provided you drive it in on an angle away from tension and deep in the ground. I had 30' of tubing with 25' of nylon masons cord tied to that. Small steel ring on cord that hooks to jet. On that ring i tied a ribbon to provide some drag. It's an excellent set up with no moving parts. I can't find my original post about the complete setup. It's on rcg somewhere.
May 23, 2010, 01:51 PM
"My grandma wants to fly jets"
heychas's Avatar

Reliability?


Can bungee launches approach 100% reliability?

I've got a "jetapult" made by fanjetusa which I like although the bungee seems a bit short (8-10' and 4' of string). I've recently been using it w/ my Sapac T-45 70mm edf (3lb 14oz AUW - 20 lbs of tension), and on the fourth flight the left wingtip caught the ground after it had flown about 10 to 15'... which caused a cart wheel It happened so fast I'm not sure exactly how it happened. I had extra "up" trim dialed in on the gear switch for launch but maybe I needed more. The plane was only about 6" off the ground when the wing dipped. I think I can repair the jet but I want a safe and reliable way to get the plane airborne.

I'm I doing something wrong or is this the risks of catapulting? If I have a 25% chance of losing a plane on the catapult (or even 10%) it seems like more risk than I can stomach.

Any thoughts?

Thanks,
Charlie
PS - Kevin C. - thanks for sharing about your club's carrier event... very cool! You did admirable despite the circumstances!


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
For Sale PRo Bungee Launch System Artsloper Aircraft - Electric - Jets (FS/W) 2 Jun 26, 2010 12:40 PM
Discussion Bungee launch height. mikey100 Australia 2 Nov 16, 2009 05:17 AM
For Sale Bungee launch dbcaster Aircraft - Electric - Jets (FS/W) 4 Oct 30, 2009 12:31 PM
Discussion Bungee Launch Hooks Leadfoot Pusher Prop Jet Models 0 Oct 23, 2009 11:29 AM