What Size Tub for a Tail Weight?

[MBDiagMan]

I am going to make a tailbob on a flat dolly for my F.  What size washtub and how many sackcrete bags?

[jetdriven]

I made a tie down out of sand bags and a piece of plywood, and a steel bar and some chain.  

[Robert Hicks]

I I forget the size of tub we used, maybe ~30 gallons? I do know it took a little less than 3 bags of concrete mix.

[Hank]

The ones I've seen have all been standard washtubs. Screw on the casters, bend a piece of rebar to attach to (so it can't pull out), make sure everything is how you want it, then mix Quikrete in your wheelbarrow and fill 'er up! Should last for decades of heavy use.

[David Lloyd]

The shop at my airport has had the bottom third of a 55 gallon drum on casters, filled with wing bolts (someone told me B-25) for 41 years.  Airport is closing, mechanic was taking everything with him, tried to lift it with an engine hoist. Just about the time it began to lift off the floor, the metal rod and hook pulled through the bottom of the drum.  Good thing it didn't happen during any of my annual inspections!

[MBDiagMan]

Thanks for your responses.

I know exactly how to make it.  What I need is the wash tub size and how many bags to get.  There are many sizes available.  I want it to be heavy enough for an F, but not too heavy.  My hangar is large and I won’t be swinging the gear of a Citation in the foreseeable future so I don’t want too much weight to move around.

Edited May 25, 2020 by MBDiagMan

[BrianWilkins]

  On 5/25/2020 at 5:06 PM, MBDiagMan said:

Thanks for your responses.

I know exactly how to make it.  What I need is the wash tub size and how many bags to get.  There are many sizes available.  I want it to be heavy enough for an F, but not too heavy.  My hangar is large and I won’t be swinging the gear of a Citation in the foreseeable future so I don’t want too much weight to move around.

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I use a different method than what you're going to make, but if it will help you calculate what you need; I found that approximately 200 lbs of weight on the tail held my E model just about right.  If you take that number and figure out the volume of quickcrete needed, you should have the info you need.

[MBDiagMan]

Yes, the required weight is what I need.  I can calculate everything else.  I thought there had been so many of these things made that people would off the top of their heads know how many bags and which size washtub.  Thanks to all.

[jetdriven]

IIRC I have 5 bags of 60lb sand.  300 lb.  I’ll take a look tomorrow at my hangar. 

[EricJ]

My IA uses about 200 lbs of stacked concrete block.    They're much easier to move around than a tub full of concrete.   I'm going to start using a Harbor Freight 1klb dolly with blocks stacked on it.   That way the dolly and blocks can be moved around easily and repurposed when necessary.    I've seen people try to dispose of concrete tubs at the airport and it's not pretty.

 

Edited May 25, 2020 by EricJ
Updated reason for editing.

[N201MKTurbo]

Any private pilot should know how to calculate this. 

I would make it twice the up force with two 200 pounders in the front seats.

[carusoam]

Some shops load bags on the wing...

Others tie the tail down...

 

The details have been covered here already...

But... if you want more....

https://mooneyspace.com/search/?&q=Tail tie down weight&search_and_or=and&sortby=relevancy
 

Best regards,

-a-

[Hank]

I thought "washtub" was  a standard size . . . .

[RLCarter]

It’s been discussed before but here is the Service Bulletin

[Guest]

I’ve got one that is a welded steel frame made of 1-1/2” angle iron on 4 heavy casters.  It holds 4- 12” solid concrete blocks (80# each) stacked 2 high on each side of a telescoping post.

Being blocks makes it somewhat portable.
 

Clarence

[ragedracer1977]

  On 5/26/2020 at 7:41 AM, RLCarter said:

It’s been discussed before but here is the Service Bulletin

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And there's a long thread on it where I think @M20Doc contacted Mooney and they said keep tying the tail down 

[jetdriven]

I have 5 bags of 60lb sand.  300 lb.  I’ll take a look tomorrow at my hangar. 

[tmo]

How are "standard aircraft jacks" called for by the SI different from non-aircraft jacks?  Is it a question of compatible support points, or is there something more to it?

[RLCarter]

  On 5/26/2020 at 3:25 PM, tmo said:

How are "standard aircraft jacks" called for by the SI different from non-aircraft jacks?  Is it a question of compatible support points, or is there something more to it?

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Probably a CYA thing

[RLCarter]

  On 5/26/2020 at 2:00 PM, ragedracer1977 said:

And there's a long thread on it where I think @M20Doc contacted Mooney and they said keep tying the tail down 

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not sure, its been brought up numerous times, I use the “A” frame method along with a tail stand, gives it 4 points and rock solid..... my pucker factor isn’t as high as it use to be compared to the 1st time 

[Hank]

  On 5/26/2020 at 7:41 AM, RLCarter said:

It’s been discussed before but here is the Service Bulletin

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Mooney says after 50 years to not hold the tail down, but to lift by the engine. Hartzell and McCauley say to not use a prop jack to lift by. Lycoming says to not lift the nose ofnthe olane using the engine, the lift points are designed to lift only the engine.

So apparently we're supposed to jack the wings and magically levitate the nose wheel into the air.

I've stacked two cases of oil, a large roll of wrenches and a couple feet of bound approach plates on my tail, then held it stable by hand.

You gotta do what you gotta do . . . .

[RLCarter]

@Hank yep, pick what your comfortable with. I had to pull the gear out of the 172 a few years ago, built the cradle per the maintenance manual, seemed like I had to jack it up into the Flight Levels before the cradle would go under it......... Jacking Airplanes up just feels wrong.....

[EricJ]

  On 5/26/2020 at 5:19 PM, Hank said:

Mooney says after 50 years to not hold the tail down, but to lift by the engine.

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I've not heard the 50-year caveat before.    Where did that come from?   Was there associated advice about tying the aircraft down for a storm with or without the tail tie down after 50 years?

[Skates97]

Cheap furniture dolly from Harbor Freight, a piece of plywood, and three 90# bags of the cheapest quick-crete from Home Depot. When not in use it is wheeled under the big shelf in the corner of the hangar.

[Guest]

  On 5/26/2020 at 2:00 PM, ragedracer1977 said:

And there's a long thread on it where I think @M20Doc contacted Mooney and they said keep tying the tail down 

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I actually checked with Lycoming, who said the engine lift ring is meant to lift the engine, not the airplane.  

Clarence