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Ballast weight for engine hung, on gear, with wings removed?

rmartingt

rmartingt

Well Known Member
Hoping to hang my engine for good in the next few weeks, and will probably be putting the aircraft on its gear (taildragger) at the same time. Anyone have a ballpark figure for how much ballast weight I'll need to keep the tail down and not nose over?

I know in the fuselage cradle I just need a sawhorse under the firewall, a strap over the tailcone, and a bucket of drywall mud sitting on the stand for good measure.

Was kind of hoping to do some canopy work first but it seems a bit chilly for that, and I'd like to minimize crawling into the tailcone as much as possible (which means delaying riveting of the upper skin).
 
5 gallons / 20 liters of water

rmartingt said:
Hoping to hang my engine for good in the next few weeks, and will probably be putting the aircraft on its gear (taildragger) at the same time. Anyone have a ballpark figure for how much ballast weight I'll need to keep the tail down and not nose over?

I know in the fuselage cradle I just need a sawhorse under the firewall, a strap over the tailcone, and a bucket of drywall mud sitting on the stand for good measure.

Was kind of hoping to do some canopy work first but it seems a bit chilly for that, and I'd like to minimize crawling into the tailcone as much as possible (which means delaying riveting of the upper skin).
Click to expand...
Assuming no wings and empennage, I was ok with a 5 gallon jug of water holding down the tailwheel on a little rolling wooden frame to hold the fuselage roughly level. Better more than not enough - would be annoying if it tipped over in the middle of hanging the engine, however unlikely that would be.
 
A RV6 or 7 with the wings on, while setting on the jack points, the tail goes negative when the plane is level (the jack points/ tie downs are well behind the main gear). We just did a weight and balance and needed to raise the plane to place the jacks under the mains and tail.

My best guess is while on the mains you will need at least 40 to 50# when the fuselage is on main gear, in level flight position.
 
I got tired of putting ballast bags on the horiz stab spar of my -6 when jacking and installed a 3/8-16 "calk-in" concrete anchor under the tailwheel, together with a lifting-rated eyebolt. SO much more convenient. With a nylon strap of suitable length, you can even use this setup with a Tail-Mate.
 
I used a 25lb bag of water softener salt. Not due to any thorough analysis of weight/moment arm, totally by TLAR and that's what was handy in the garage :)
 
I Just did this to my build. On the mains, no tail or wings, but the aft end still in the cradle to keep it level. It's basically neutrally balanced right now with zero weight on the tail. I strapped 3 cinder blocks to it just to be sure.
 
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