[GeoffH]

Hello, on the hobbyking webpage I came across hydraulic brakes and kits to convert pneumatic retracts to hydraulic. I did not know such a thing was made.

http://www.hobbyking.com/hobbyking/s...Retracts_.html

http://www.hobbyking.com/hobbyking/s..._Assembly.html

http://www.hobbyking.com/hobbyking/s...0mm_tyres.html

They seem to be made by UMS in india
http://www.umstech.in/view_products....=Landing Gears

Don’t want to even start discussing hobbykings quality but has anyone ever used hydraulic gear before or what other manufactures offer these? My initial thought would be the retracts are just going to be more complex and heavier creating more possible problems then they would solve.

I can see hydraulic brakes having some real advantages in theory but wonder how they work in the real world and what type of servo would be required to actuate the master cylinder to get enough breaking force?

Geoff

[Cougar429]

I saw one other company recently that offered the hydraulic retracts. Can't remember where, though.

I would think with the advances in servoless retracts these might be an interim solution. As of the last week even Robart has offered servoless retracts, teaming up with Down And Locked. Prices are rather rich for my blood.

Would be interesting to see electric brakes come out soon as they would be a lot less complex.

[Ramz]

I am betting you will see electric retracts gain in popularity once you see an affordable electric brake system (for turbine models anyways). As of right now, whether you have pneumatic, electric or hydraulic retracts, you still need compressed air for the braking....so if you have to have an air tank and all that goes along with it, you might as well just make it all pneumatic imho. I would think it would be very easy to gear up electric brakes with some electro magnets. Time will tell.

[Pauld]

The Carf MIG 29 is supplied with hydraulic powered retracts which in the original generation were crap. Apparently resolved now. I have seen the set being installed on a kit and these ones included locking valves in the cylinders.

The main advantage would be realistic operation (speed) and no air system to charge every time. Disadvantage is the bleeding procedure and an extra onboard battery.

PST also still supplies some of thier kits with hydraulic brakes which apparently work well.

A nice combination would be electric retracts with hydraulic brakes which would provide simplicity and no air fill requirements for either.

PauLD

[Angus]

looks like a good smoke pump

[Pauld]

I wonder if the flow rating would be right for smoke?

PaulD

[luv2flyrc]

I had hydraulic brakes on my PST Panther and didn't like them. Replaced with air. They were a pita anytime maintenance had to be performed on the retracts, brakes or wheels. I can't see hydraulic mains being any fun either.

I love the idea of electric but, you either have to hang a servo on every gear door or run air on the doors anyway. In that case, you may as well go air on the retracts as well.

I have found if you use good lines fittings and valves, air can hold for weeks in the system.

Mike