SKIS AND SKI FLYING

[buchanan]

I’m fairly new to ski flying and completely new to AK ski flying. I had a set of Aero 1800’s on my Super Cub when we were in MT.

I flew our 170-B yesterday with Landis 3000’s. What I’d like to know is why there are two bolts (actually only the nuts) protruding from the edges of each ski right at the pedestal? They are on the edge of the skis and go through the aluminum edge strip on each side. I’m thinking they may be for braking action when you are on ice or hard packed snow. Next…I have the pungi cord type system to keep the tips up against the check cables. I’m wondering if they are okay in the cold or does one need springs? The guy at Landis told me when I bought them that they were made from good rubber and wouldn’t loose their elasticity when it got cold. It was –20 yesterday AM when I plugged it in and they seemed to rebound fairly well. Last……How are you guys lifting your skis up to get some dunnage under them so they don’t freeze down. With my Cub it was just a matter of picking up the tip and putting something underneath. I’ve figured out a 2X4 lever and a couple blocks to allow me to stick something underneath but I can only get the shim about half way from the tip to the pedestal. What if your shim freezes and you can’t get it out? With the bolts protruding from the bottoms there is no way you can taxi from on top of the dunnage…………Don’t ask me how I know.

Any comments, pointers, books or helpful hints will be much appreciated.

Buck, Galena, AK

[spiro]

bolts thru the skegs - you guessed right. On glare ice you will slide a *long* way without them. The drag is hardly noticable in other conditions.

pungi stakes are sharpened bamboo sticks, sometimes with excrement on them. Bungee cords are elastic, which do fine in the cold. Springs, like Atlee's, are preferred by many but not approved on Cessnas. I've got springs on mine but they were installed before the latest round of FAA madness.

I've no good solution for getting up on dunnage if you're solo.

been quite cold here but little snow. Thinking about trying my lake on wheels tommorrow.

- paul

[buchanan]

Thanks Paul for the clarification of punji and bungee........brain short or some other feeble excuse. I should know pungi. I had 32 months in Viet Nam but none of it on the ground; thank heaven.

Does the dunnage ever freeze and become a problem getting out? Do you have Landis skis?

We don't have any snow up here either. The ski strip still has some gravel poking out.

Buck.........Galena

[mit]

Buck
I don't put mine on anything. When I leave town and there is frost on them I drag it around with the pick-up. In remote sights never had a problem had to lift the T/W out of the overflow once. I have heard of plastic trash bags put over them. I never tried it? Do you have the new Teflon bottoms?

[N419A]

Well my goal for the weekend was to put my skis on, as close as I got was putting new threw bolts on (new goal is to do it befor T-day). I need the bolt because I taxi down the road from my house to the airstrip and there's one stop sign I go through. With out those bolts some days there's no stopping (I have UHMW bottoms and skegs).

I think the bungis are fine there only enemy is time and UV (like everthing).

As for blocking up I have Landis 2500's and I use a 6 foot 2x4 as a lever and slide 16" pieces of 4x4's under the skis. You just need to get the block under there enough to get 75% of the ski off. As for the blocks freezing down, I give them agood wack with the 2x4 then pry up and pop them out.
Everyone like picture:

Have fun, Paul K.

[buchanan]

Thanks Guys,

The skis are new Tim. I bought them while we were down states but we never had the snow stay long enough to justify putting them on. Montana chinook zone. I also had the Cub at that time. Day before yesterday was their virgin flight. They have UHMW bottoms and skegs on the edges with through bolts.

Nice picture of yours Paul. It looks like you have new, plus 10%, UHMW on them.

I think the 2X4 lever and blocks to get some dunnage under them will work. Maybe I’ll just experiment without anything and see what happens at least while I’m close to a pick-up or snow machine. There is a Super Cub on the field from Tok flying moose surveys and I see he doesn’t put anything under his Northland boards with UHMW bottoms. The locals not on wheel skis all put something under them though.

One more question. I’m pulling the airplane into the tiedown (there are airplanes behind me) with a tow-bar on the tail wheel using my pick-up. I’ve towed spray airplanes a lot that way down states with a 4 wheeler but never with that kind of resistance that the ski through bolts provide. Do you think I’m putting too much torque on the vertical “king bolt” that the tail-wheel pivots on? This are the only set of tie-downs with electricity close to them.

Thanks again, Buck……..Galena, AK

[futr_alaskaflyer]

We just wedge one 2x4 as far under the ski as possible using another 2x4 as a lever...with a little kicking and cursing it usually makes it about half way from the tip to the pedestal - it's enough to get maybe 2/3 of the ski off the snow.

Also our tiedowns back up to a fence and there is no turning into them with straight skis. Instead we have a come-a-long staked down which we attach to the tailwheel spring to ratchet the plane back into the tiedown. I haven't noticed it putting any particular strain on the skis so long as you guard against the rear tip digging into the snow.

[mit]

Buck

Come see me when your in town. I will tell you everything I know about what to do and what not to do with skis. It should take about 30 sec then we can BS for hours about flying!

[Paul-WI]

All this talking about Ski flying gets me excited! I am finally getting the skis on 58D next week during my annual. Lakes are just starting to freeze over so maybe in a few weeks I'll be joining the ranks of the Ski plane Pilots

I will be taking lots of pictures during the install and hope to take a lot of winter pictures as well!

Paul
N3458D

[spiro]

my home base, LHD (Lake Hood Seaplane), had over 12" of ice as of last Friday, 11/17. I was still on floats 10/23!

[Bill Hart]

my home base, LHD (Lake Hood Seaplane), had over 12" of ice as of last Friday, 11/17. I was still on floats 10/23!

Just how thick should it be before one would consider skis? Down here in Ga we just don’t know these things.

[pdb]

Just how thick should it be before one would consider skis? Down here in Ga we just don’t know these things.

Bill:

I usually wait until the trucks have stopped falling through the ice before I put my plane on skis. .. It happens every year so its a pretty good indication.

[spiro]

Just how thick should it be before one would consider skis?

much depends on the ice quality, temp, and duration of load. Cold, clear ice maybe 2-4" for people, 4-6" light aircraft, 6-8" cars & light trucks, 20+" dump trucks, 30+" almost any kind of heavy equipment. Parking for more than a couple hours requires more.

short answer: about 6". Up until a couple years ago LHD didn't officially open until there was 8", when it would support grooming equipment. Then they dropped a machine thru a thin spot and now the official number is 12".

[denalipilot]

Does anyone have a good trick for stretching the forward springs/ bungees from the ski tip up to the cowl attach point? It always seems to be an epic struggle with my 170B on Aero 3000's. I have jacked the gear to be able to raise the ski tip toward the cowl, and I have tried getting friends to raise the tail to bring the nose down nearer to the ski tip. Neither way is easy. I think cold bungees are probbably harder to stretch, but since I don't have a heated hangar I don't have good options for stretching them while warm. Today I thought of attaching the bungee first and then mounting the ski on to the axle second, but that seems like a sure way to mangle something (ski, axle, ...fingers!!)


Thanks. -DP

[hilltop170]

denalipilot-
I have Atlee's springs on my wheel skis and had the same problem with stretching them.

I made a fixture out of two lengths of 1/2" conduit with through-holes drilled at each end. To figure out how far apart to put the conduit holes, install the skis and measure how much the spring needs to be stretched to install them, then add a couple of inches.

I put the spring lengthwise between the two lengths of conduit and put a long bolt through the holes at one end of one conduit, the loop on the end of the spring, and through the other conduit.

I then stretch the spring with a cherry-picker engine hoist and put another long bolt through the other end of one conduit, the spring loop, and the other conduit. This holds the spring in the stretched position for installation on the airplane.

If you don't have an engine hoist, another person can stick the bolts through the fixture and spring while you stretch the spring. Not quite as safe but works ok as long as you make sure the spring is held firmly while it is stretched.

To remove the fixture from the spring, simply step on the front of the ski and pivot it down until the spring stretches enough to remove one of the long bolts. Or, if the ski is flat on the ground, stretch the spring by hand and have someone else pull the bolt. Either way, the fixture is then free.

Use the same process in reverse to install the fixture and remove the springs from the plane next spring.

This is the safest way I could think of to do the job myself.

It would be easier to visualize with a picture but I'm in Texas and the fixture is in Alaska.