CTSW suspension

[Ed Cesnalis]

I don't understand my suspension. The gear legs are straight, thick-walled aluminum tubes. There is no 'spring' or give there until you damage it.  The leg hard fits on either end.  

I assumed there is some shock absorption in the design but where is it and how much good is it?

I have over 1200 landings and this system works fine for me.  Am I relying on only soft landings?

 

 

[Anticept]

It's still metal tubes. They have an elastic range. Go beyond that, and you hit the yield point, when damage occurs from permanent deformation.

[Roger Lee]

Stay with all soft landings. The aluminum legs have some flex,but since there is no way to know exactly when you exceed that it would be too late. The 2006 CTSW had an upgrade to slightly beefier legs and front end.

[WmInce]

Others may disagree, but I have found some landing gear shock absortion can be controlled by the amount of air pressure in the tires. That recommendation came from a very experienced CT pilot/A&P mechanic, who has flown, sold and worked on CT's for many years. I used to run 32 PSI in all my tundra tires. The past 18 months, upon his recommendation, I reduced my main gear tire pressure to 25 PSI. It has provided a bit more cushion, but I always try soft landings anyway, and avoid any side loading during landing, rollout or taxi. I run 30 PSI in my nose wheel tire.

YMMV, but I have had good results so far.

[Roger Lee]

You can do that with the larger 6.00x6 tires, but not very well with the smaller 4.00x6

[Tom Baker]

The CTSW landing gear, at least the heavy gear, are solid aluminum rods, not tubes. They are however counter bored on the ends, about 8" on the top and 2" on the bottom. Their design for shock absorption comes from alloy and how they are machined. They are very stiff, but have some flex before they bend taking a permanent set.

[WmInce]

Tom,

Is the "heavy" gear the tapered type legs?

[FredG]

The CTsw Parts and Assembly Manual (Release 5, Issue 21, January 2008) refers to the main gear leg as the "main spring bar" (page 116).  Translation is always a consideration, but that suggests some "spring" in the suspension.  I recall watching a CTsw land somewhat deliberately a couple of years ago.  I watched as the gear legs spread on initial touchdown and then return (presumably) to their unloaded geometry.  Looked to me like they provided some flex to the gear.  

[CT4ME]

I would have to agree.  Just pushing the aircraft around on the ground, you'll notice the spread of the gear will change a bit.  It's not unusual to lift the wing (so the gear also lifts), and see the gear spring back to it's unloaded position.

[Anticept]

Springs can be anything. Even uncoiled steel like leaf springs.

As for tire pressure: low tire pressure makes softer landings, but can result in spinning the carcass, and sometimes the tube. Not good on the valves. Just avoid high speed touchdowns and you should be good.

[Tom Baker]

2 hours ago, WmInce said:

Tom,

Is the "heavy" gear the tapered type legs?

All of the "Heavy" gear legs I have seen were tapered, with flats machined on 2 sides.

[Ed Cesnalis]

I guess I see it now.  Instead of rotating at the fuselage attachment upon hard landing the gear leg bends as a spring.