I have a  Zenith CH-801 with asymmetrical  landing main landing gear due to a hard landing.  Have you any recommendations regarding ways to make the main gear symmetrical again?  

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Replacement is probably your best bet!  Once a gear has been bent, it's very difficult to get it "square" again.

I have heard of people doing it with ratchet straps, but I don’t know how exactly - I assume they attach one end of the strap to the gear near the fuselage and the other end near the opposite wheel to pull that wheel in and down. Whether or not it’s safe to do so probably depends on how badly it’s bent.

Note that if you do bend them, they won’t be as strong as they were originally and if you bend them back and forth in an effort to get them perfectly aligned then they might break instead of bending on the next hard landing (from being work hardened). I would also do some research before using any heat to make the bending easier because heat treatment can really change the characteristics of a metal - if done right, it could remove the work hardening and make them like new, but if done wrong it could have the opposite effect, making the metal stiffer and more brittle.

Good luck!

Thank you for your reply.  If the gear were to be replaced and or bent using a heavy duty press, how exactly can the fuselage/wing be suspended?

Saw horses!

Saw horses!  Of course.  My real question was if there are lift points on the fuselage that work best for raising the fuselage enabling saw horses to be placed beneath the fuselage.  As you can tell, I am a new owner of the 801.  I most certainly appreciate everyone's comments.

Of course, the 801 is heavier, but on my 750 STOL, I can easily push the tail down enough for an assistant to slide a sawhorse under the fuselage forward of the gear (with a cut-out to clear the central C channel stiffener that runs fore and aft) and then put a shoulder under the fuselage near the tail and lift the tail enough for another sawhorse to be slid under the fuselage just aft of the gear and forward of the "hell hole" belly hatch.  This results in all the wheels being off the ground.  But, as I said, don't know with the additional weight of the 801 if this is practical or not.

John

N750A

A couple of older Workmates have worked for myself on my 701 and for a friends 701 as well. Vice section is opened to span gear opening. 801 is heavier so you have to judge whether they would be strong enough. 

I’ve got a couple of thoughts on supporting the 801 during gear exchange…..


1). The best option is to support the 801 from the main wing root by adding a bracket to the forward spar bolt.  This will allow you to attach a spreader bar and lift from above.  If the airplane was not built with brackets here,  they can be added.  It would require removing the root skin,  supporting the wing, fabricating a lift bracket, and installing that bracket with a longer spar attach bolt.  It is not extremely difficult, and will make future lifts simple (provided you have an over head lift option).  

2) It’s possible to support the aircraft from below and remove the gear,  but it would be a multi step process.  You would need to remove the gear spring retaining nuts, then build something to support the 801 resting on the end of the studs.  Whatever you built would need to be able to then lift the 801 up until the gear was well off the bracket.  Then you would need a second support device to hold the airplane up by the gear bracket at the point where the gear normally holds it up.  Once that was in place you could remove the first support and pull the gear free.

Either method will be a little work, but doable.  I would suggest the first, because chances are you will one day want to lift if again….. and the second time is super easy with #1.

3). I would not suggest attempting to support the 801 by the cabin floor.  This would be OK if the engine was out I think,  but I would think the risk of damage is too high, and the damage that could happen too hard to fix for the potential benefit.

4). I suspect if will be very difficult to get the gear back to the original shape,  unless you have access to a major league press with appropriate dies.  Personally I would just order a new gear.  Talk to Michael at Zenair Canada.  I think they have them on the shelf from the 801 SD project.  Grove also sells a gear for the 801 - but there is lead time. If you want to get fancy,  Grove will gun drill the brake lines and it comes out super cool.

Thank you for your very thorough reply.  You and the other Zenith owners who have replied have all been very helpful.  I am so enjoying the flight time that my CH-801 has provided.  Having purchased the aircraft in June, so far I have logged 40 hours.  All hours have been great fun :)  Each flight hour takes at least an extra 30 minutes as people are always asking questions about the 801.  

I’d call Roger at Zenith and ask for advice from the kit manufacturer. I can safely and easily lift my 701 from the underside directly in front of the gear mount brackets using a floor jack and a straddle cradle I built out of 2x4s. Then I slide two jack stands under my cradle and can easily access the gear mount fasteners and remove the main gear spring. But I will never again lift it from the tail as John can do with his 750. That results in damage to the forward Z angle that frames the belly access hatch on my 701.  Because your airplane is larger and heavier, what works for us may not work for you.

Oh, and order a new main gear spring when you talk to Roger.  Once it’s bent, it’s spent. And no local fabrication shop really wants to do a one-off job, especially when they learn it’s for an aircraft.  

I so appreciate everyone's thoughts and suggestions.  I have decided to order a new main gear for my CH-801 from Zenair in Ontario.  They have the gear in stock and ready to ship.  Cost is $1600 plus shipping.  The Grove landing gear was tempting but their cost was $2519 plus $300 for gundrilled brake lines plus shipping.  Grove landing gear is not in stock with estimated product availability being unknown.  Again, thank you so much for your many thoughts and suggestions and ideas.  Go Zenith! 

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