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  • piperdgh

    jacking points

    Can anyone tell me where you jack a colt to remove the landing gear. Are there any specific jacking points? Doug
  • JohnW

    #2
    No, there are no specific jackpoints. I am of the opinion that lifting the airplane by the Lycoming lifthook on the engine is a VERY foolish form of "Russian Roulette". The mere THOUGHT of a chuck of cast aluminim hanging from the hook and a legless wounded bird lying broken on the floor underneath it, is beyond my imagination. Some would say there is "No such scenario" and report they have done it repeatedly, but I have seen the pictures of the "hook/broke bird thing, and they ain't pretty! Oh, I also don't care much for the "Bogi-lift" idea that runs a strap under the crankshaft behind the prop, either. That might be okay for a quickie tire change, but I don't care for the idea of slinging a thousand pound side-load onto my crank (others don't seem to mind, tho'...) for even a few minutes... and "overnight!?!?! No thank you, very much.

    How I "sling" a ShortWing is to remove the top cowl entirely (WoW! four screws!!!) and then putting a woven "tow strap" through the engine mount top legs (I use a 2X4 "spreader bar" located just above the boot cowl between the strap to prevent "rolling") as far "up against the firewall" as you can get it -loosen and reposition or remove something "easy" like an air-oil separator- and then "pick" (lift) with a chain fall. You want to NOT be flexing the engine mount out in the "open" between attach points. No "bending, please. Come-a-longs are too "labor intensive" (and I like to be able to count to ten just before I roll in between the sheets, every night) for my liking and have somewhat of a "tenuous grip on reality" as far as I am concerned (especially in the "down" mode), but COULD be employed if you had to.

    Another "good way" is to remove the wing root fairings, and use the method many floatplane drivers (and Uncle Sam, for many decades) have used over the years. You bend up a pair of .125 steel "U-shaped lifting hook" and mount one on each of the front spar attach bolts. Tapping the "correct" bolts out and temporarily installing longer bolts for this is much easier than you might think (use the services of a Warm Body at the tip to "unweigh" the tension on the attach bolt and NOTHING else needs to be removed to swap these bolts. DO recommend caution in "manhandling" the wooden tip bow...extreme force is NOT required and a broken bow is UGLY to repair. Easy does it is all it needs. "Fancy lift hooks" for this purpose have a hog ring welded to them but a simple 45 degree (or so) bend in the top side of the bracket works perfectly well (a lot of Cubs that switch wheels for floats often have a ring mounted on a hinge pin so they flip flat and are left installed UNDER the root fairing -or some similar design- but this really isn't necessary for what is basically a "one-time" operation). Then you lift by the hooks at the front wing hinge (same deal... use a spreader bar here, as well). Uncle spec'd their Wartime Aeroncas to be delivered to Depot with said lift brackets installed on every airplane, and the Champ and Chief Manuals (civilian included) all listed the attach bolts at that point that are 1/4" too long for installing the wings WITHOUT that fitting included. The extra 1/4" was for the two ends of the .125" thick lift hook bracket. Either method gives you quite enough "security" to feel good about letting 'er hang for as long as is necessary (a decent attach point for the fall in the hangar you are tying up is, naturally, presumed!). Seems like if you have BOTH MLG coming off, you intend to be "legless" for more than a few minutes. Securing the tail "skid" on the Trike is a definate "must do", and a weight on a "table" at approximately the correct height to fit under the tail "at rest" works fine. I've seen a COUPLE of cement blocks be "enough", but in MY mind, like Mic Jagger said: "too much is never enough"). If you are the "nervous type", using the overhead lift allows you to lower the airplane down onto a couple of horses, but BE ADVISED that the MLG fittings on the fuselage can be BENT (and MUCH EASIER than one might think!). Still, a light "contact" on horses might (I stress "might") be in order if you are still squeamish.

    Comment

    • Geoff Newcombe
      Master Forumator
      • Aug 2005
      • 297

      #3
      " ..... but I have seen the pictures of the "hook/broke bird thing, and they ain't pretty!"

      I have seen this too --- follow John's advice --- it is the bestest and safest way to go!

      Comment

      • Tom T.
        Official Forum Resident
        • Sep 2005
        • 1461

        #4
        Ya know, one guy can pick up one side at a time, easier with 2, thats what I had to do to get it on the scales. Then have someone slide a saw horse uner one side at a time if need be.
        Tom T.

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