Axles

Bill Rusk · Post by **Bill Rusk** » Wed Nov 13, 2002 1:46 pm

OK, so if I replace my axels with solid ones per the Type Data Sheet, do I need a 337 or can it be done with a logbook entry? Do I need a IA to sign it off or can an A&P sign it off? Gotta keep it legal.

Thank you

Bill Rusk

Post by **GAHorn** » Wed Nov 13, 2002 2:54 pm

An A&P may sign it off in the airframe log as a "minor" alteration. (It's an approved part as it's listed in the 170 Type Cert.)

N3243A · Post by **N3243A** » Wed Nov 20, 2002 8:19 pm

I can see there is quite a bit of confusion concerning axles and ski compatibility. First off, your installation configuration depends totally on the type of ski you intend to use. Aero Ski and Federal straight skis have steel pedestals which are stronger and consequently narrower and are designed to operate within the confines of the bearing stop or shoulder which is machined ridge about 3/4 of the way down the axle. This ridge is there to prevent your wheel assembly from sliding up against the axle bolts and gear legs.

If you are using Landes Airglass skis, they are of course made from fiberglass with a steel tube embedded in the fiberglass which your axles rotates in. Because they are fiberglass, Landes made the ski pedestal wider which means the ski needs to slide deeper onto the axle. So for Landes installations the bearing stop or shoulder needs to be machined down to 1.5 inches so that the ski can slide down enough to get the axle nut on. As for the bushings used on these machined axles, you must have two sets. A short set for the skis, so that they don't hit the axle bolts and a longer set which are for your wheels. Typically these bushings are made from 1.5" ID 4130 steel tubing 0.063" thick. Some minor relieving of the bushing where it tries to but up against the axle face between the NAS bolt heads may be required because there isn't much space between the bolt heads and the axle. You don't really need drawings to make these bushings, it's not rocket science. Just make some carefull measurements and a little trial and error.

Iv'e said it before and I'll keep saying this, if you intend to operate on skis get rid of the aluminum axles, (solid, hollow, whatever) PERIOD. Do your airplane a favor and install STEEL axles. These will withstand abuse much better than the aluminum ones. You don't abuse your airplane you say? Wait to you get in 15 inches of overflow and start horsing that 1600 lb monster around to get unstuck. Been there, done that, got the T-shirt.

Bruce

funseventy · Post by **funseventy** » Wed Nov 20, 2002 9:23 pm

Atlee Dodge has the spacers setting on the shelf waiting for you to call. I think he wants 15 dollars a piece. That's alot in my opinion but if you don't have the material or a Lathe it can save you some headaches.

The solid aluminum axles can be used for wheels as well as long as you have these spacers. The parts from Atlee have a nice radius on the inside of one end. This goes to the inboard, if you turn it around the squared off end will ride on the radius at the axle flange and crack, YUK!! Please pay attention to these little details.

Kelly

Bill Rusk · Post by **Bill Rusk** » Thu Nov 21, 2002 3:10 am

Great stuff. Thanks for the inputs guys. I just got the NAS bolts in and will try to get some mounting done this weekend. When I do I'll put an update here as finding the NAS bolts was an adventure to say the least. Keep the info coming, its a big help to us "outsiders".

Bill

N3243A · Post by **N3243A** » Thu Nov 21, 2002 3:39 am

funseventy wrote:Atlee Dodge has the spacers setting on the shelf waiting for you to call. I think he wants 15 dollars a piece. That's alot in my opinion but if you don't have the material or a Lathe it can save you some headaches.

The solid aluminum axles can be used for wheels as well as long as you have these spacers. The parts from Atlee have a nice radius on the inside of one end. This goes to the inboard, if you turn it around the squared off end will ride on the radius at the axle flange and crack, YUK!! Please pay attention to these little details.

Kelly

Kelly can say it better than I, I learned much of this stuff from him. He also got the T-shirt for taking my passenger out of the overflow ridden lake while I limped out on takeoff over the trees, stall horn blaring, globs of frozen overflow hanging off the skis!

Bruce

Trapper · Post by **Trapper** » Thu Nov 21, 2002 3:42 am

Thanks to the help from this group, I now have a set of spacers so I won't have to change my axels every time I change from wheels to skis, or vise versa.
I am using Airglass skis and the solid axels wouldn't allow me to used my wheels without changing axels. Only took a machine shop a short time to make a set of spacers, however I haven't seen the bill yet.
Thanks again guys for all the help.
Trapper

flyer170 · Post by **flyer170** » Thu Nov 21, 2002 1:55 pm

Bruce.... I have Federal skis and solid steel axels. I used them last year and I have a question on installation. From the inboard side to the outboard side I have a large washer, rubber sleve, ski, rubber sleve, large washer, axel nut. I tightened the axel nut against the outboard washer until the ski seems secure. I still seem to get quite a bit of defelection side to side from the ski. Are they suppose to be loose, tight, what

Where can I find assembly drawings that would include this info.
Do you use bungees or springs

I have bungees but they need to be changed. My neighbor has springs on his PA12 and Aero skis
I agree about all the force, twisting and turning etc. I haven't run into river overflow but I have on run into slush on lakes

I would like to know also about your experience on taxing around on skis.
If I have a wide open lake, no problem lots of room. But a narrow strip and cross wind

I had an 11AC Chief that I flew for years on skis and it had a much shorter turning radius. I feel like a idiot with the 170

Bob

Trapper · Post by **Trapper** » Thu Nov 21, 2002 3:37 pm

Bob, if you are using the 0-300 or C-145 engine the 170 is a little short of power especially in overflow or deep powder snow. Tight turniing is a bit of a problem. I fly with a 20ft length of rope tied on the tail, it makes it much easier to jump out and turn the plane by hand. I also use a snowmobile to help turn in real tight spots. If I am going to stop in these tight spots I always turn the plane around and have it facing takeoff direction before leaving. Nothing worse than coming back and have a plane froze up and facing the opposite direction from your desired takeoff. I also use a tail ski as the 170 is quite heavy on the tail. If you are flying in remote areas always carry survial gear, snow shoes and a shove.
Good Luck
Trapper

flyer170 · Post by **flyer170** » Thu Nov 21, 2002 6:19 pm

Trapper... Thanks for the reply. I have the C-145. using a rope on the tail is a good idea, instead of trying to force it around in a small area. I should get out more. I could lift the tail of my Chief but not the 170. I use a wheel penetration ski for the tail wheel.
I carry a survival kit summer and winter and just adjust the contents for the season.
What about bungees vs springs for the rigging, I need to replace my bungees

What amount of side to side movement of the skis do you get

Bob

funseventy · Post by **funseventy** » Thu Nov 21, 2002 10:30 pm

With Federal skis it is common for the spring tension tostart to toe in the skis. This is normal, if they are loose all the time it might be time for new rubber sleeves. I saw a guy was advertising those parts on Barnstormers2000.com. Spring vs. Bungee, in my opinion the bungee is the reason behind needing safety cables. Atlee Dodge has ski springs for sale. His number is 907.344.1755. He sells two different types, gold for 180/185 and silver for cubs, 170, etc. The color specifies heavy or light springs, because the faster airplanes need more tension. When he sends them to you he will supply you with a chart that shows the amount of stretch you need for a given tension. The amount of tension is called out in 43.13, and is based on ski size, I believe. Its been a while since I looked. It might be cruise speed.

Hope you have fun, Kelly

N3243A · Post by **N3243A** » Thu Nov 21, 2002 10:41 pm

flyer170 wrote:Bruce.... I have Federal skis and solid steel axels. I used them last year and I have a question on installation. From the inboard side to the outboard side I have a large washer, rubber sleve, ski, rubber sleve, large washer, axel nut. I tightened the axel nut against the outboard washer until the ski seems secure. I still seem to get quite a bit of defelection side to side from the ski. Are they suppose to be loose, tight, what Where can I find assembly drawings that would include this info.
Do you use bungees or springs I have bungees but they need to be changed. My neighbor has springs on his PA12 and Aero skis
I agree about all the force, twisting and turning etc. I haven't run into river overflow but I have on run into slush on lakes
I would like to know also about your experience on taxing around on skis.
If I have a wide open lake, no problem lots of room. But a narrow strip and cross wind I had an 11AC Chief that I flew for years on skis and it had a much shorter turning radius. I feel like a idiot with the 170
Bob

Bob,
I use bungees but when the the time comes to replace will be going with the Atlee Dodge Springs. But I guess these require a field approval but that shouldn't be a big deal (in AK anyway)

Lot's of real estate seems to be the norm for taxiing these things around on skis. If I need to turn around, I don't go where I don't have at least 30-40 yards of room to execute a 180 turn depending on snow conditions.

Bruce

flyer170 · Post by **flyer170** » Fri Nov 22, 2002 3:21 am

Thanks for the input on the ski equipment (I've printed it out) and hearing that I'm not alone in being challenged moving that puppy around in the snow.
We don't have any white stuff yet. The lakes are freezing up so I might have my fish shack out by mid Dec. Maybe Christmas time.
Bob

Trapper · Post by **Trapper** » Fri Nov 22, 2002 3:52 am

Dos Atlee Dodge have a web site? How much do these springs cost?
Thanks Trapper

zero.one.victor · Post by **zero.one.victor** » Fri Nov 22, 2002 6:16 am

All this talk about turn-arounds on ski's makes me think of the old truck-drivin' song: "Give Me Forty Acres and I'll Turn This Rig Around" !

Eric

The International Cessna 170 Association

Axles

Axels and 337's

Axel Spacers

Using Skis on 170

Springs in place of bungees