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General control line discussion => Open Forum => Topic started by: Martin Quartim on March 04, 2015, 05:50:09 AM

Title: New Retractable Landing Gear System
Post by: Martin Quartim on March 04, 2015, 05:50:09 AM

I became friend with a new C/L flyer  and he has a lot of creativity. I have been helping him developing his new model and he wanted to make it with retractable landing gear.

He first thought about using the system from Jomar, but he did not like it so he made a new one and he asked to share this video of his system with you all:

https://www.youtube.com/watch?v=jiq_wqRVrNk

The system senses when the engine starts and stop with  rpm sensor with two magnets on the spinner. He said the total weight of the LG with battery and cables is about

He also told me that the "CPU" can be used to control a flap tab and rudder.

He plans to produce in quantity to sell and he would like your feedback to see what demand there is for a product like this.

Martin






Title: Re: New Retractable Landing Gear System
Post by: Allan Perret on March 04, 2015, 06:44:10 AM
The weight is missing.

What about cost ?
Title: Re: New Retractable Landing Gear System
Post by: Keith Miller on March 04, 2015, 07:20:10 AM
I think that's clever!
So, you're caught tweeking the needle valve longer than expected and the gear retracts while you're walking out to the handle.  I imagine there would have to be some way for the launcher/helper to trigger the system to ensure the gear doesn't retract for some time period after launch.  Or maybe an accelerometer that doesn't trigger the system until it sees >1G acceleration towards the outboard tip.

Title: Re: New Retractable Landing Gear System
Post by: Paul Smith on March 04, 2015, 08:24:16 AM
2.4 is the way to go.  100% off the shelf and it's all simple plugin stuff.
Title: Re: New Retractable Landing Gear System
Post by: Martin Quartim on March 04, 2015, 09:49:52 AM
Bob Thank you for your valuable input! I will pass on. I had no idea Radio Control was legal now.

Martin
Title: Re: New Retractable Landing Gear System
Post by: Martin Quartim on March 04, 2015, 09:54:21 AM
The weight is missing.

What about cost ?


Hi Allan,

He said the weight is about 5.4Oz for everything and the cost will be around $95.00

Martin
Title: Re: New Retractable Landing Gear System
Post by: Tim Wescott on March 04, 2015, 10:47:53 AM
4.5oz sounds right (or maybe a bit light) for gear, battery & all.  It's way too much for just the electronics.

The TUT could do this with an appropriate script, but if your quantities are high enough a purpose-built timer would cost less.
Title: Re: New Retractable Landing Gear System
Post by: Fred Cronenwett on March 04, 2015, 08:53:11 PM
We have been using electric retracts with the 2.4 Ghz system in CL scale since 2013 and I did a video showing how to setup retracts if you want P-51 gear doors.

For CL stunt lose the gear door sequencer, gear door servos and the gear doors and just plug the electric retracts into the receiver and you are ready to go. I also have other videos on my channel that show how to setup and use the 2.4 ghz systems. Get a small battery to keep the weight down

https://www.youtube.com/watch?v=SWBBAQH8MOY

this video shows the basics of 2.4 Ghz and some basics of the electric retracts.

https://www.youtube.com/watch?v=BWv1RIX1eWE

Fred
Title: Re: New Retractable Landing Gear System
Post by: Randy Cuberly on March 04, 2015, 10:07:57 PM
Hmmmm.
That's pretty cool Fred.  If they aren't too heavy I think the gear door sequencer and servos would be very useful and cool on a stunter.  The wing could stay very clean when the gear is retracted.  Just looking at the video they don't appear to be very heavy.

Randy Cuberly