Sport Cub/Carbon Cub VS Super Cub 3x3 gear differences

[Pete D]

I've had several people asking why the Sport/Carbon Cub 3x3 gear costs more than the Super Cub gear. It comes down to the shock strut design, and since it can be hard to describe over the phone if you've never seen one, I thought I would give an opportunity for people to see what the differences are.

Super Cub shock struts are multi-piece design, where the lower shock strut (the part that is replaced in in the 3x3 gear mod) bolts onto the hydrasorb unit (the hydrasorb unit is what the bungees mount on). So when bolting on an extended gear system all that is replaced is the lower shock strut-the original hydrasorbs and bungees are re-used.

Sport and Carbon Cub shock struts are a full length assembly from the axle to the cabane vee-the bungees actually assemble onto ears that are part of the shock strut assembly. Thus, when you want to make the shock strut longer, the entire assembly including the bungees needs to be replaced. I'm not sure how much more time there is in fabricating the parts that make up the assembly, but I do know that there is approximately TWICE the time just in welding all the pieces together, as compared to the Super Cub lower shock strut assembly.


0110011057.jpg
/\ SUPER CUB /\
The lower shock strut is on the left, this is what is changed out in a Super Cub installation. A simple tube with some holes and bushings in it. The black part on the right is the hydrasorb assembly, this is what holds the bungees.


0110011057a.jpg
/\ SUPER CUB /\
Lower shock strut. Bolts to the inboard end of the axle, and bolts onto the hydrasorb. This is what is replaced with a longer one.


0110011057b.jpg
/\ SUPER CUB /\
Hydrasorb assembly, would have bungees wrapped around the ears. Bolts to the lower shock strut and the bottom of the cabane vee. Typically covered with an aluminum fairing.


0110011527a.jpg
/\ SPORT & CARBON CUB /\
Close up of shock strut assembly, extended. The bungees would pull the two sets of ears closer together except when absorbing landing loads. (pardon the rust-this would not go on an airplane looking like this)


0110011527.jpg
/\ SPORT & CARBON CUB /\
Shock strut assembly, un-extended. Bolts to the inboard end of the axle and goes all the way up to the lower part of the cabane vee. Typically the upper portion with the bungees wrapped around the ears would be covered with a similar (though smaller) fairing as the Super Cub one, making it look very close to the same externally.

[rfriend]

How does this work with the aoss sytem? Still a little unclear for layman like me.
Will take off distance be affected on carbon cub with new extended gear?
I understand one can break harder therefore reducing landing distance.
Maybe a quantitative number or percentage could be shared. Maybe Jim's performance before and after distances could be shared.

thanks

[Pete D]

This will work with the AOSS system, in that case you would replace the entire shock strut assembly, both on Super Cub or Carbon Cub, just as you would if you were putting AOSS on the standard gear. The AOSS struts just need to be ordered longer.

I don't think takeoff distance would change at all. This is the same gear we had on N155PC at the Valdez takeoff contest in 2010 and it sure didn't seem to hurt it there :-)

Pete D.

[randylervold]

rfriend,

As Pete indicated the AOSS assembly replaces everything he's pictured. In terms of shorter takeoff or landings with the 3x3 gear though it should be understood that it takes a very experienced pilot to use the extra angle-of-attack and weight bias afforded by the 3x3 gear to gain any advantage. I fly our planes all the time and though I know I can brake a bit harder on landing with the 3x3 gear but I'm not sure I could measure much of a difference reliably. Heck, when landing on wet grass the wheels just skid anyway regardless of what landing gear you have. Here's the reality of the situation: a really good pilot with standard gear could outperform a mediocre pilot (like me for example) with the 3x3 gear.

IMHO one should never be landing on any strip or gravel bar where an extra 10-20 feet of landing distance would make a difference between damaging the plane or not. So, if one is configuring the best possible backcountry airplane the 3x3 gear is worth considering, but if you don't have it your Carbon Cub is still going to be capable of both taking off and landing shorter than anything else out there anyway.

[RanRan]

rfriend,

Here's the reality of the situation: a really good pilot with standard gear could outperform a mediocre pilot (like me for example) with the 3x3 gear. .

Gotta love ya, Randy.

[rfriend]

rfriend,

As Pete indicated the AOSS assembly replaces everything he's pictured. In terms of shorter takeoff or landings with the 3x3 gear though it should be understood that it takes a very experienced pilot to use the extra angle-of-attack and weight bias afforded by the 3x3 gear to gain any advantage. I fly our planes all the time and though I know I can brake a bit harder on landing with the 3x3 gear but I'm not sure I could measure much of a difference reliably. Heck, when landing on wet grass the wheels just skid anyway regardless of what landing gear you have. Here's the reality of the situation: a really good pilot with standard gear could outperform a mediocre pilot (like me for example) with the 3x3 gear.

IMHO one should never be landing on any strip or gravel bar where an extra 10-20 feet of landing distance would make a difference between damaging the plane or not. So, if one is configuring the best possible backcountry airplane the 3x3 gear is worth considering, but if you don't have it your Carbon Cub is still going to be capable of both taking off and landing shorter than anything else out there anyway.

Copy---"Less than mediocre pilot"

[couleeone]

Isn't that part of the reason other than pitch attitude on takeoff is for under fuselage clearance for off airport landings? I know on my S1 I have had problems with the radio antenna hanging below the fuselage getting knocked around several times and have needed small fabric repair underneath a couple of times.

That what happens when you are a medicore pilot!

Geo

[RanRan]

Isn't that part of the reason other than pitch attitude on takeoff is for under fuselage clearance for off airport landings? I know on my S1 I have had problems with the radio antenna hanging below the fuselage getting knocked around several times and have needed small fabric repair underneath a couple of times.

That what happens when you are a medicore pilot!

Geo

That's what happens when you're a bush pilot. You know, bushes! Then you get to talk about the 'scares.' Does it get any better? You're a lucky man.

[Pete D]

Then you get to talk about the 'scares.' Does it get any better?

"Bad decisions sometimes make good stories"

When I'm about to do something, I try and remember to ask myself "is this going to make a good story?" If so.....maybe I don't want to do it! :-)

Pete D

[RanRan]

"Bad decisions sometimes make good stories"

When I'm about to do something, I try and remember to ask myself "is this going to make a good story?" If so.....maybe I don't want to do it! :-)

Pete D

I meant to say 'scars' not 'scares' - as in dings and dents to a bush plane, not the pilot. lol