Jacks

[Kerrville]

I don’t see a major threat, to life and limb anyways. If they leak, even with the gear up, it goes down to the level of the jack not all the way to the ground. Then it would just be an issue of figuring out how to get that side up enough to put the gear back down. Am I missing something?

[MikeOH]

16 minutes ago, Kerrville said:

I don’t see a major threat, to life and limb anyways. If they leak, even with the gear up, it goes down to the level of the jack not all the way to the ground. Then it would just be an issue of figuring out how to get that side up enough to put the gear back down. Am I missing something?

You could be right....what about the prop if the blade is straight down,...what happens if one side's seal suddenly fails? Will the shock knock the plane off the jacks?  Why do the commercial aviation jacks have locks?  Probably just me from many years of working on cars, ALWAYS with a jack/safety stand.

[Kerrville]

I know. I wish there were a jack point and a point for a stand. I never go under my truck unless it is supported on jack stands, not the jack…

[PT20J]

I'm not too concerned about the Mooney. Now, when we used to jack up the DC-3 at the museum to swing the gear -- that always got my attention.

[IvanP]

On 10/12/2024 at 11:40 AM, PT20J said:

Alpha 324 24” jacks work fine with my M20J. My pucks are pretty new. 

Same here. I have three 24" Alpha jacks for my Bravo (using one for the nose instead of tying the tail down).

[JimK]

When I first got wing jacks for my Ovation I jacked it and left it overnight with gear down.  When I returned the next day both jacks were down and one of them had leaked oil all over the hanger floor.  Since then I block the jacks to prevent lowering.  Another good reason to block the jacks is that one could leak down causing a gross mismatch in height and a possibility of the airplane slipping off of the jacks.

[Fly Boomer]

2 hours ago, JimK said:

When I returned the next day both jacks were down and one of them had leaked oil all over the hanger floor

What brand were those jacks?

[bigmo]

I took the good advice here and added a set of clamping shaft collars on my jacks. A set of nice stainless collars was around $35. I put them on the jack, lifted 1/2 my truck (about 2000 pounds), released the jack valve and let it sit all night. All good, didn't budge a single millimeter. They take about 30 secs to set once the jack is in place. Kind of a no brainer.

I had intended on building a set of sawhorses to size and place them on the rib Mooney specifies (as an emergency). But the collars will suffice as my backup.

[IvanP]

18 hours ago, JimK said:

When I first got wing jacks for my Ovation I jacked it and left it overnight with gear down.  When I returned the next day both jacks were down and one of them had leaked oil all over the hanger floor.  Since then I block the jacks to prevent lowering.  Another good reason to block the jacks is that one could leak down causing a gross mismatch in height and a possibility of the airplane slipping off of the jacks.

This is precisely the reason why we should always use safety collars or safety bolts when jacking up the plane. Even if you just lift the plane to change tire.