Sneasle

Kinda interesting. Still a bit much for all small stuff, but interesting non the less. Anyone seen these before who might know how the weight compares to that of mech retracs in this size?

http://www.advantagehobby.com/produc...1&cat=0&page=1

SquirlNutZipper

My Feedback: (9)

More tech details would be interesting. I for one am wondering how many times the system works before being recharged as it has a one-way valve. Also what is used to pressurize the canister in the first place?

A better system could use a geared servo attached to a pump and use fluids instead of air. The benifits would be smaller lines and also a stronger, more stable pressure to keep the landing gear in place. But, get a hole in the line with either works and that could spell doom for the aircraft.

I would say mechanical retracts are a better option for smaller planes. Less to go wrong with electrical systems. Sub-micro servos are also probably more positive and weigh less than all the lines, connectors, etc...

hogflyer

The picture isn't clear enough to tell if it's and air-up/air-down, or air-up/spring down system. The one way valve is the refill valve used to fill the system with compressed air, and if it's like a typical pneumatic retract system, it'll use about 100 - 125 psi.

I'm curious how much weight it will support, and how many cycles it gets on a charge.

Hogflyer

jetpack

My Feedback: (1)

That looks just like a common cosmetic bottle for air. I bet it just brings the gear down after a hand launch and has to be recharged each time.

EASYTIGER

My Feedback: (119)

I have them. They are nicely engineered in some respects, not so in others.
Firstup, they are really for something a pound or less. The struts are thin and weak, the frames are plastic.
Secondup, I have had issues with the press-fit air cylinders popping off their mounts under pressure.

The do work, you get four or five cycles per air fill, they operate at around 100psi.
Squirrelnut, you use a robart hand pump to fill them up.
Mechanical versus air, well, mechanical only SEEMS simpler, but in most tri-gear applications, it's really not either simpler or lighter, which is why, except for 60 and smaller sized taildragger warbirds which use one servo and mechanicals, pneumatic is almost universally used.

This company has a sturdier version of these retracts coming out, with metal frames, hold off for them.

Elvis B

My Feedback: (9)

I have some coming, but is the strut metal so you can make an axle or is it carbon and you need an axle.