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Happy New Year fellow "Z"s!
Am considering going with dual brake calipers on my standard stock STOL750 with single caliber Matco brake assembly and Turf-Glide tires. The Matco wheels are rated for the change to dual calipers and Matco makes the assemblies for the change relatively easy. My question to ponder is this - what real advantage will I be gaining in doing the change to dual calipers? I ask this because I find that the light weight of the aircraft, tire surface area contact with the ground and friction of the ground surface all combine to allow the aircraft to "skid" forward (brakes are locked and wheels not rotating) during close to full power runups. It seems that the physics of the problem boil down to lack of suitable friction between the tire and the ground and not the energy dissipation capability of the braking system. Admittedly, the total energy of a landing aircraft is much greater than during a static runup and requires more energy dissipation overall, but I just can't see any obvious substantive advantages of going to dual calipers with the wheel/tire combo for short field landings. Let's discuss...! As always, thanks for all thoughts and opinions.
Mighty "Sky Turtle" 826DE
If you are thinking of going dual caliper just do it. You will be happy with the results. Yes you can get by with single but the dual you don't need to stand on the pedals so hard when running up and they just work better across the board.
I've never had a plane with duals. But owning different motorcycles the difference was absolutely amazing.
My personal experience is that it depends on the size of the tires, My first EAB I started out w single pucks, and had big tires. Couldn't hold it on run-up and couldn't stop the plane on landing either. Added dual and it was an amazing difference. But these were large tires...not sure what you're running. Nevertheless after that experience there was no question to go with duals. Bought duals and fitted them on my Cruzer before selling it, When you need brakes you NEED them, Also had brake pedals each side.
My Edition 1 STOL 750 came with dual caliper Matco brakes as standard equipment. IMHO you can never have too much brakes, and they work well on paved surfaces. However, I operate off grass most of the time and my STOL 750/Jab 3300 will easily take off on grass with wheels locked! Don't ask me how I know! LOL!
I would go with dual caliper brake kit. I always had "weak brakes" on my CH601HD. I installed "Matco Intensifier kits" and promptly blew the brake lines off.... performance was not increased and I eventually crushed the smaller piston parts. I finally bit the bullet and redesigned the complete Zenair brake pedal geometry (the way it should have come from factory) to get adequate brakes. The dual caliper kit is the way to increase stopping or holding power. Being high a HP to light weight airframe means you will still skid the tires across the grass / tarmac.
If you swap out to 26" Airstreaks and run them at 6 psi you will have plenty of traction to justify those dual pucks! :)
Maybe one day?
Thank for all the input everyone. Now I have to confess that I feel like an idiot. While doing research for parts on the Matco website, I realized that my wheels labeled MH6BD.75XT were for the dual caliper setup. I found that interesting and was wondering why I had only one caliper setup. After talking with George at Matco, he thought It would be very unusual to run a single caliper with that wheelset, and to check to see which brakeplate I actually had; one for the single caliper or the one for the dual caliper. So, this afternoon I took a look at the wheels and finally noticed that I indeed have two calipers per side! I am at a loss as to why I was under the mistaken impression that I had only one caliper but here is the proof! I suppose that dual caliper setup is standard equipement with the kit, but I had forgotten about that? I never felt that stopping was an issue. on asphalt...now I know why!