Jacking up your plane

[Jabiru7252]

Interested in what you folks use as a jack if/when you end up with a flat tire out at some remote strip. I'm trying out a few ideas for my Jab. Need something that can be carried in the plane without too much weight or bulk yet be safe and easy to use.

 

 

[brucechurch]

Interested in what you folks use as a jack if/when you end up with a flat tire out at some remote strip. I'm trying out a few ideas for my Jab. Need something that can be carried in the plane without too much weight or bulk yet be safe and easy to use.

[SDQDI]

Aww I thought I was going to find a thread of these

 

 

As it turns out I can't be of much help, I carry one of those aerosol goo cans just in case but I haven't had any hassles since I put goo in my wheels. Running the bush wheels i have never had any balance issues but have heard from some people that the goo gives them horrible out of balance problems.

 

With the aerosol cans I have had mixed results one particular brand kept blowing the lid when the tap was turned but the one I have now has worked fine. (So far only used in anger on farm bike tyres.)

 

 

[spacesailor]

You could use a "cam wheel" , there was one designed specifically for trailers at one time. very light ,remove the axel stub & it all lays flat. maybe some-one will produce a "cad" drawing for you One circle, one axel, two nuts to bolt axle to cam-wheel, that's it for left & reverse circle on axle for right.

 

spacesailor

 

 

[djpacro]

Apart from the cans of magic goo .....

 

For the Pitts I modified an automotive scissor jack which picks up on a bit of steel tube on the landing gear truss opposite the axle, behind the wheel/brake. Used it a few times.

 

 

[aj_richo]

Peter Anson, Sonex pilot and Engineer extraordinaire has designed and manufactured a light weight jack for Sonex aircraft.. 400+grams

 

could easily be adapted to other aircraft

 

http://www.ansoneng.com/sample-page/products-summary/quick-lift-wheel-jack/

 

 

[Guy s]

What a nifty gadget Aj and might look into this as I've often wondered when travelling outback how I'm going to get the wheel of if I had too.

 

 

[old man emu]

Whatever jack type you use, don't forget to include a solid base plate for the jack, otherwise it will sink into the ground.

 

1. Try to locate the data obtained when your aircraft was weighed for weight and balance calculations. This will give you the weight borne by each wheel.
    
    
   
2. Work out the dimensions of the base plate required to support this weight using these figures for soil density:
    
    
   

 

 

Dry density in g/cm3 *

 

Sand = 1.52

 

Sandy Loam = 1.44

 

Loam = 1.36

 

Silt Loam = 1.28

 

Clay Loam = 1.28

 

Clay = 1.20

 

Concrete = 2.40

 

Dry density for most soils varies within a range of 1.1-1.6 g/cm3

 

* Multiply these values by 0.001 to get an answer in kg/cm3

 

 

 

OME

 

 

[rgmwa]

How do you get the required bearing area from the soil density OME?

 

rgmwa

 

 

[frank marriott]

For aircraft with undercarriage similar to a Jabiru this is light and practical. Obviously if a second person is around it is better as you just lift the wing and the other person puts it under the undercarriage leg. On your own then it would require digging.

 

 

 

[old man emu]

How do you get the required bearing area from the soil density OME? rgmwa

I thought that it would be an easy calculation, based on the compressibility of soil and the force each wheel exerts on the ground. Unfortunately I could not get any typical values for soil compressibility, so without data, the calculation can't be done. I was wrong to suggest soil density had anything to do with it.

 

I suppose another way to do it would be to work out the area of the tyre's footprint. To do this, jack up a wheel and paint the tread for about a quarter of the circumference with anything that will act like ink, possibly engine oil. Then place a sheet of white paper on the ground under the wheel and lower the wheel onto the paper. Lift the wheel off and retrieve the outline of the tyre's footprint. The footprint should be somewhat oval in shape. For practical purposes, draw a tight fitting rectangle around the footprint and using the measurements for the length and width, make up a support pad which has the same or slightly greater area.

 

OME

 

 

[rgmwa]

A piece of 150 x 250 timber should just about do it for any reasonably firm ground.

 

rgmwa

 

 

[old man emu]

For something lighter, what about a thin kitchen chopping board?

 

 

 

[rgmwa]

Good thinking, OME. Can use it for lunch too.

 

rgmwa

 

 

[Nobody]

For something lighter, what about a thin kitchen chopping board?

Some chopping boards can be quite slippery. We used to cut them up to make cheap bearing surfaces when I used to sail skiffs.

 

 

[brucechurch]

Interested in what you folks use as a jack if/when you end up with a flat tire out at some remote strip. I'm trying out a few ideas for my Jab. Need something that can be carried in the plane without too much weight or bulk yet be safe and easy to use.

Please give me a ring have sketch for simple jack for jab 230 mob 0407277039

 

 

[Jabiru7252]

Whatever jack type you use, don't forget to include a solid base plate for the jack, otherwise it will sink into the ground.

1. Try to locate the data obtained when your aircraft was weighed for weight and balance calculations. This will give you the weight borne by each wheel.
    
    
   
2. Work out the dimensions of the base plate required to support this weight using these figures for soil density:
    
    
   

 

 

Dry density in g/cm3 *

 

Sand = 1.52

 

Sandy Loam = 1.44

 

Loam = 1.36

 

Silt Loam = 1.28

 

Clay Loam = 1.28

 

Clay = 1.20

 

Concrete = 2.40

 

Dry density for most soils varies within a range of 1.1-1.6 g/cm3

 

* Multiply these values by 0.001 to get an answer in kg/cm3

 

 

 

OME

Hmmm, density of soil and human brain are pretty close - no wonder we have 'dirty minds'.

 

 

[Kununurra]

For something lighter, what about a thin kitchen chopping board?[ATTACH=full]50257[/ATTACH]

And a set of steak knives with this

 

 

[old man emu]

And a set of steak knives with this

Yes, Tim. And half of Tasmania, too.

 

 

[rickodesu]

You forgot the block of flats too

 

 

[MarkyMarkOZ]

Aww I thought I was going to find a thread of these[ATTACH=full]50238[/ATTACH]

As it turns out I can't be of much help, I carry one of those aerosol goo cans just in case but I haven't had any hassles since I put goo in my wheels. Running the bush wheels i have never had any balance issues but have heard from some people that the goo gives them horrible out of balance problems.

 

With the aerosol cans I have had mixed results one particular brand kept blowing the lid when the tap was turned but the one I have now has worked fine. (So far only used in anger on farm bike tyres.)

The Aerosol cans work well. The reason some people have balance issues with them is that they dont rotate the tyre and the goo settles on the bottom. Taxi around slowly for a minute after putting half a can in. Stop, put the rest of the can in, then taxi around slowly a minute again. This step is essential to not only spread the goo evenly, but more importantly, ensure the goo gets into the area that needs repairing. All fixed - no heavy jack required.

 

 

[spacesailor]

Half The picture is all I could get, For a hollow aircraft axle, a bolt through the apex of a disk ( nut both sides) to fit into your axle will do the same as an elaborate costly unit.

 

Different wheel size put the bolt-hole closer to the disk centre or smaller disk & cut a recess for your axle if needed.

 

spacesailor