Ski Rigging Instructions

[behindpropellers]

I have some Federal ski rigging drawings I am going to scan in and turn into a PDF file later today. If you would like me to email you a copy (today) please send me a PM and I will send it out before leaving work.


Tim

[behindpropellers]

If you reply to me please be sure to include your email adress in your PM.

Tim

[C-YQK]

Please send me your drawings
Thanks
Gary
snstlimo@voyageur.ca

[cubdrvr]

I read Cuby's posting of a cub in ID that flipped over when a ski cable broke. I assume both the bungee and cable failed. I've wondered if anyone else has had that happen and how you would handle the landing. Rigging instructions show 20-35 degrees down angle from level for the front cable so if the bungee fails it looks marginal that the ski tip would rise to normal on landing or have the tip dig in the snow. It seems the 20 degree cable angle would be plenty to accomodate any humps or downhill operations and the 35 a little excessive. Any advice from you ski bums?

[funseventy]

I am a firm believer that 20 degrees is plenty. But more importantly, lets talk about basics of ski airmanship. If the bungee or spring fails and the safety cable holds it the airplane will be out of trim from the ski hanging. If you were to slow up to almost a stall the air would pick it up, now accelerate to a speed that is lower than your normal cruise for increased angle of attack and it will stay up. Now there isn't any risk on landing as it is up out of the snow at touchdown.

[Big AK]

And we're assuming the "ski cable" was NOT the aft one and we're assuming that it (the cable and/or bungee) broke before the incident.

The aft check cable breaking would make this scenario a bit tougher to deal with.

I also agree that 20 degrees of ski-tip DOWN is plenty. And also that 0-1.5 is enough ski-tip UP.

[don d]

I'm Not sure what happened to the cub in McCall, Id.. Seems to me if you drop a cub from 4' into 4' of soft snow the back check cable will probably break when it goes over on it's back. I'm new to skiis and was operating near McCall yesterday and the snow while not powder is pretty soft down acouple of feet. My check cables only maintain my ski position in flight and really have no purpose when the ski is on the snow. Or am I missing something.

Don

[Wingie]

Wow, Don; I am REALLY sorry for your bad luck!

Now I had spent about 45 minutes earlier this afternoon baring my soul in the confession about ranking out some innocent Farmer's barbed-wire fence with my Vagabond on Federal 1500 skis back in 1979. But I must have timed out (I type ONE fingered) because I lost it into Cyberspace when I tried to post it. The SHORT version is that I failed the upper REAR check cable attach fitting on the left hand ski. (too bad you're missing all the gory details...but I'm DRAINED from the LAST TIME I wrote about it). The ski went to Wedding Night Attention with the tip up against the front wing lift strut.

Well, I had to land SOMETIME, so I did so back at my own place. I did a full right slip (against the locks) and the tracks in the snow tell the tale that right wing tip was LOWER than the surface of the snow. The ski flipped (with a Bullet) back down, and the landing was otherwise pretty uneventful. I taxied comfortably back to the hangar and shut down, mistakingly believing that not all that much could have been damaged. WRONG! While the rest of the airplane was remarkably UNSCATHED, the left ski from aft of the pedestal had departed the airplane at touchdown! I went over that airplane with a fine toothed comb, an "IA knife" and cans of dye pen. No damge found. It didn't fly again until August of the following Summer for all the fabric work (thanks to one of the most humid Spring and Early Summers I ever remember). Nothing but the left ski, which looked like it was cut off on a bandsaw and hand-filed smooth about 1/2 inc behind the pedestal.

So, is THIS the way to SAVE an airplane with the rear check cable failed? I don't know. But under those conditions, THAT DAY, with the Planets all lined up just so and my tongue sticking out "just so"- it worked for me. I recommend this little "joyride" to absolutely NO ONE. Do NOT try this at Home, WITH or WITHOUT Adult Supervision.

Just for the record, even at the eyewatering speeds attainable in the Vagabond (like trimmed for 55mph), it was absolutely IMPOSSIBLE to push the ski forward off the strut using the snowbrush I kept in the airplane. It was like it was WELDED to the strut! Plus, of course, it would have been a joke trying to hold it anywhere NEAR level and accomplish any kind of a landing.

So, I'm right up there as one of the Luckiest People I Know, and yeah, Big AK. You right about it being tough to deal with. But I gotta think if the FRONT check cable broke (and I doubt even if the bungee was still there that would stop the ski going overcenter once caught in the airload), there would be no way to NOT flip the airplane. Just like the .mpg of the Cessna Amphib touching down on the water with the wheels DOWN. RIGHT NOW, upsidedown! But on the Vagabond, the ski in the full tip UP position was overcenter with the tail pointing slightly forward. When it hit the soft snow that way and tore off the skitail, the front part rotated into position and all the way to the hangar I had no clue there was anything wrong with the ski. If the part of the ski FORWARD of the pedestal were to break off, you ain't done having FUN just yet! I dunno for sure. But I'm not intrigued enough to go out and try it.

[funseventy]

The Funny thing is that, that was the short version! :lol:

[S2D]

Had a friend try to kill a coyote with his ski one time cause he left the gun home . :drinking: You don't even want to think of trying that one at home. He got a real close up and personal look at a dead coyote. :yeow:

[behindpropellers]

This should clear it up. On another drawing I have it says 20-35 degrees.
http://www.supercub.org/upload/BehindPropellers/scan0002.jpg

[T.J.]

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