Aircraft jacking using a weighted tail stand Vs using a cable winch

[Jpravi8tor]

I understand that you can jack the aircraft using a weighted tail stand, does anyone use a hand winch between the tail tie down and the tie down imbedded in the ground?

[PT20J]

As long as the anchor in the concrete is secure, it shouldn't matter. You don't even need a winch; just the right length of chain and a couple of screw pin anchor shackles should hold the tail while you jack up the wings.

[M20F]

[Jpravi8tor]

I’m aware of the service bulletin and every time I see a Mooney on jacks the tail is attached to a weighted tail stand,

I don’t like the idea of using a tail stand but it seems to be the only choice at times.

i suppose I should ask if anyone has suffered damage or had issues as the result of using a tail stand?

[Raymond J1]

 

 

A 17 Gallons metal barrel with 10 Gallons of water and that's enough.

 

[EricJ]

1 hour ago, Jpravi8tor said:

I understand that you can jack the aircraft using a weighted tail stand, does anyone use a hand winch between the tail tie down and the tie down imbedded in the ground?

My hangar neighbor with an M20A just puts a length of chain from his tail tie-down to his floor anchor.     He knows just how long it needs to be so that when he jacks the wings up and puts them on his sawhorses that the airplane will be reasonably level with all the wheels sufficiently off the ground.

In my hangar there's an enormous expansion joint right down the middle of the floor where an anchor would need to be placed, so I use a stack of old brake rotors on a wheeled dolly and then block the dolly wheels.   It's been working great so far, and disassembles if I ever need to move it very far.

[Jpravi8tor]

Another question then is …. What is the safe minimum weight to use when constructing a rail stand ?

10 gallons of water = 83.5 lbs plus a 10-15 lb barrel just doesn’t seem enough!?

[Guest]

It’s not just the amount of weight needed to hold the tail down.  It’s enough weight to add stability to the airframe while jacking the wings.  For long bodies we use three jacks for everything else we use two jacks and a weighted tail stand.

[N201MKTurbo]

The first thing I did when I got my hangar in 93 was put an anchor in the floor to hold the tail down. It is a 1 inch diameter by 8 inch long lead anchor. It took almost 2 hours to drill that damn hole with a hammer drill. I was surprised how thick the concrete was and the aggregate seemed to be mostly granite. I’ve been using the same chain for 30 years now. It has served me well.

[A64Pilot]

I use an engine hoist and soft straps to lift the nose, only way you can jack a J model and comply with Mooney instructions that I can figure is soft straps lifting on the engine mount.

Mooney must have a reason to write that SI

[PT20J]

Every shop I know uses a tail weight except Don Maxwell who uses a couple of old alternator belts around the prop blade shanks and an engine hoist. Mooney's suggestion to use the lifting eye on the engine is absolutely against Lycoming recommendations and if you look at the amount of metal in the crankcase at that point it doesn't seem a good idea. But then, that same service bulletin tells you that you can't fly with with the tiedown eyes installed. Anyone follow that recommendation?

Skip

[Guest]

15 minutes ago, PT20J said:

Every shop I know uses a tail weight except Don Maxwell who uses a couple of old alternator belts around the prop blade shanks and an engine hoist. Mooney's suggestion to use the lifting eye on the engine is absolutely against Lycoming recommendations and if you look at the amount of metal in the crankcase at that point it doesn't seem a good idea. But then, that same service bulletin tells you that you can't fly with with the tiedown eyes installed. Anyone follow that recommendation?

Skip

I wonder what Hartzell and McCauley would think about lifting the plane by the propeller blades?

[M20F]

32 minutes ago, M20Doc said:

I wonder what Hartzell and McCauley would think about lifting the plane by the propeller blades?

Probably the same thing Mooney would think with you using a tail stand. 

[PT20J]

4 hours ago, Jpravi8tor said:

Another question then is …. What is the safe minimum weight to use when constructing a rail stand ?

10 gallons of water = 83.5 lbs plus a 10-15 lb barrel just doesn’t seem enough!?

I don’t know what the minimum is. The weight I borrow looks to be about a third of a 55 gallon drum of concrete - call it 20 gal. Concrete weighs about 20 lb/ gal, so about 400 lb. It’s very stable.

[Hank]

5 hours ago, Jpravi8tor said:

Another question then is …. What is the safe minimum weight to use when constructing a rail stand ?

10 gallons of water = 83.5 lbs plus a 10-15 lb barrel just doesn’t seem enough!?

My old IA used a galvanized washtub on wheels, full of cement with an eye bolt welded to a bent piece of rear so it couldn't pull out. It was heavy!

[Guest]

7 hours ago, M20F said:

Probably the same thing Mooney would think with you using a tail stand. 

Perhaps, but lifting the nose by the propeller blades puts unknown loads on the bearings which are normally under centrifugal load when the propeller is spinning.  The tail tie down is quite strong, and as long as it hasn’t been ground thinner by ground contact, I will continue to use it.

We need @201er to conduct another poll on what method people are using and how many have seen damage by not following the S/I

[skykrawler]

I don't think the force required to lift the nose by the engine strap is is anywhere near the weight of the engine itself.

[A64Pilot]

1 hour ago, skykrawler said:

I don't think the force required to lift the nose by the engine strap is is anywhere near the weight of the engine itself.

Anyone got a copy of the weighing for a 201 laying around? weight on the nose wheel would tell the tale, fuel is so close to CG I don’t think it would matter much.

[ArtVandelay]

Anyone got a copy of the weighing for a 201 laying around? weight on the nose wheel would tell the tale, fuel is so close to CG I don’t think it would matter much.

It’s about equal on all 3 points, of course then you have mechanical advantage of the arm of the tail.

[Lionudakis]

I believe the airframe, engine, and prop folks are all covering their respective behinds. I have seen a failed engine hoist that dropped the nose. Bet he wishes he'd not followed the SL

[PT20J]

3 hours ago, skykrawler said:

I don't think the force required to lift the nose by the engine strap is is anywhere near the weight of the engine itself.

According to the Lycoming Operator’s Manual, the IO-360-A1B6D weighs 330 lbs. When we reweighed my M20J, the weight on the nose wheel was 639 lbs.

[PT20J]

46 minutes ago, ArtVandelay said:

It’s about equal on all 3 points, of course then you have mechanical advantage of the arm of the tail.

On mine it was 639 lbs on the nose, 788 on the left main, 800 on the right main, with full fuel.

[PT20J]

The distance from the jack points to the tail tie down is approximately twice the distance from the jack points to the nose wheel. So, if the weight on the nose wheel is 639 lbs, the weight at the tail to create a balancing moment would be about 320 lbs. You’d want more to offer stability.

Skip

[Jpravi8tor]

I believe I will build a simple portable wooden A frame hoist lifting on the engine lift point and use a come along between the tail tie down and tie down ring, thus distributing the load and providing additional stability and safety.

https://www.google.com/search?rlz=1C9BKJA_enUS842US856&hl=en-US&q=a+fram+hoist+wooden&tbm=isch&sa=X&ved=2ahUKEwi1qYjI-pn7AhWym4kEHQIxAyEQ0pQJegQIBhAB&biw=1024&bih=653&dpr=2#imgrc=unNwC2ubhZAlcM

[carusoam]

One of the most challenging oil leaks to fix…

Comes from the silk thread that lives between the case halves of the engine….

 

Oddly….

The engine hoist eye is in the same general area, isn’t it..?

 

Coming from a machine building background… lots of electric motors get lifting eye bolts…  specifically, to aid in motor replacement…

I wouldn’t ever think to use that eyebolt to lift the machine around it….   

 

I would be inclined to ask a mechanical engineer about…..

Never mind, I can hear Hank laughing at me already…..    

Best regards,

-a-