Aluminum firewall thickness

[Bruce]

The CP's state you can replace the stainless steel firewall (.016) with aluminum, do you use the same thickness for the aluminum? I couldn't find the thickness in the CP's or I missed it.

 

Thanks,

Bruce

[chasingmars]

The CP's state you can replace the stainless steel firewall (.016) with aluminum, do you use the same thickness for the aluminum? I couldn't find the thickness in the CP's or I missed it.

 

Thanks,

Bruce

I wouldn't... I had thought, from memory that it was the other way round, that RAF had put something out saying that it should be stainless and not aluminium for the Longs etc... on the Cozy I gather it's remained aluminium in the plans. But to me, I think, despite the fact that it's supposed to be the fibrefrax that provides the heat shield, it should be stainless or titanium for a firewall.

[chasingmars]

I wouldn't... I had thought, from memory that it was the other way round, that RAF had put something out saying that it should be stainless and not aluminium for the Longs etc... on the Cozy I gather it's remained aluminium in the plans. But to me, I think, despite the fact that it's supposed to be the fibrefrax that provides the heat shield, it should be stainless or titanium for a firewall.

It's amazing what 2 minutes and google can turn up...

 

I'm wrong, what I was remembering is the "mandatory" replacement of aluminium control system components behind the firewall.

 

What you are remembering is true, it's in CP #25

FIREWALL - LONG-EZ AND VARIEZE

We now approve the use of fiberfrax (a space age ceramic material) as a

replacement for asbestos. Since fiberfrax is as good a fire barrier as

stainless steel, we approve substituting .016 2024 T-3 aluminum for the

stainless. This saves almost 2 lb at the firewall. Both Wicks and

Aircraft Spruce are now shipping kits with fiberfrax and aluminum.

 

Installation of fiberfrax is as follows: Complete airframe

construction through cowling installation, then remove everything from

the firewall bulkhead, and install fiberfrax with a bead of silicone

around the edge of the bulkhead. Do not wet out fiberfrax with epoxy.

Now install the .016 2024 T-3 aluminum which is required to protect the

fragile fiberfrax, from local damage, abrasion etc. See plans changes

section of this newsletter.

I'd still not put in an Aluminium firewall, but that's just me (and, of some import to me anyhow, Transport Canada, who apparently won't give me a special airworthiness cert if I were to)

 

... and, um... asbestos? There are Longs out there with Asbestos firewalls?!

[tom rodgers]

What realy happend was

 

1. It was stainless firewall

 

2. Aluminum was approved as a with fiberfrax

 

3. After a accident investigation aluminum components were changed to steel and a fireproof coating or stainless became manditory

 

Unfortunatly all the updates are not clearly printed in one place

 

Tom

Long ez builder N141tr

[Bruce]

What realy happend was

 

1. It was stainless firewall

 

2. Aluminum was approved as a with fiberfrax

 

3. After a accident investigation aluminum components were changed to steel and a fireproof coating or stainless became manditory

 

Unfortunatly all the updates are not clearly printed in one place

 

Tom,

 

Could you give us a little more information about the accident, more importantly for me, who changed it back from CP #25 and where is the change located?

 

Thanks,

Bruce