Alloys for certified parts?

"Vaughn Simon" wrote

While I believe you are on the winning side in your argument about
aircraft materials, the Zodiac may not be the best example to prove your
point. As an LSA, tt is certified to an industry standard, not an FAA
standard. I recently checked out in one and it even has a "warning" in
the cockpit to that effect.

Yes, BUT don't let that warning read with too much meaning, either.

The warning is there, just as the warning in experimentals. It reads that
this aircraft does not meet the qualifications of FAA certified aircraft, or
something like that. I'm sure most of you remember exactly what that says.

It should be noticed that while it has not been compared directly to the FAA
standards, there are many, many homebuilts that far exceed the FAA
standards. Some of the quality in homebuilts make certified aircraft look
like erector set airplanes, in comparison. g
--
Jim in NC

On Aug 1, 12:17 pm, "Morgans" wrote:
"Vaughn Simon" wrote

... As an LSA, tt is certified to an industry standard, not an FAA
standard. I recently checked out in one and it even has a "warning" in
the cockpit to that effect.

Yes, BUT don't let that warning read with too much meaning, either.
...
there are many, many homebuilts that far exceed the FAA
standards. Some of the quality in homebuilts make certified aircraft look
like erector set airplanes, in comparison. g


Of course. As I pointed out to the Bradley Aerospace
(Bradley Aerobat) company rep, 6061 T6 has 95% of
the yield strength of 2024 T3, and better corrosion
resistance so that you can make back some of that
minor weight penalty by using less paint.

He keeps harping on how 6061 is not "aircraft aluminum".
So I asked him which standards organization sets the
standards for "aircraft aluminum". His response to that
was to delete my earlier article comparing 2024 to 6061.

http://groups.msn.com/bradleyaerobat

As far as I can tell, "aircraft aluminum" is marketing hype
used to promote non-aviation products to a naive public.

As such, the term fits right in with Bradley Aerospace's
approach to marketing.

--

FF

"Morgans" wrote in message
...

"Vaughn Simon" wrote

While I believe you are on the winning side in your argument about
aircraft materials, the Zodiac may not be the best example to prove your
point. As an LSA, tt is certified to an industry standard, not an FAA
standard. I recently checked out in one and it even has a "warning" in the
cockpit to that effect.

Yes, BUT don't let that warning read with too much meaning, either.

I don't, or I wouldn't have bothered checking out in the plane. My comment was
only to point out that the OP might want to find a more bulletproof example to
prove his point.

Vaughn

I worked for one of the major A/C manufactures and they used 6061 for
several welded assemblies including the nosewheel fork , they formed the
parts cold and we pre-heated and welded the assemblies and they were sent
out for heat treat to bring the parts back to the T6 condition or about 35 K
Tensel , I can't ever remember seeing a piece of alum. or steel that said
aircraft on it , a Mil. spec no. might be stenciled on sheet , most
structural alum. used in A/C construction is 2024-T3 . Phil L.
wrote in message
ps.com...
I have run across someone who insists that
6061 T6 is not "aircraft grade aluminum".

He claims that there are no certified parts made
from 6061. I find that hard to believe. Aren't there
certified aircraft with welded aluminum frames?

--

FF

wrote in message
ps.com...
I have run across someone who insists that
6061 T6 is not "aircraft grade aluminum".

He claims that there are no certified parts made
from 6061. I find that hard to believe. Aren't there
certified aircraft with welded aluminum frames?

--


Seems like the drop tanks on the F-15 were 6061, they were certainly
weldable. Possibly the early Harriers too. Been too many years to recall for
sure. I welded on both of these programs at McDonnell Douglas, back in the
70s.

wrote:
I have run across someone who insists that
6061 T6 is not "aircraft grade aluminum".

He claims that there are no certified parts made
from 6061. I find that hard to believe. Aren't there
certified aircraft with welded aluminum frames?

--

FF

On the Canadair RJs, the leading edges are 6063. The flappers for the
cabin inflow check valves are 3000 grade, basically aluminum siding
material.

Parts for an aircraft can be made from cast iron if the manufacturer
qualifies the part to whatever spec is applicable. Certified grade
material more relates to QA processes, not the specific alloy.

In avionics, manufacturers have been forced to move away from mil-spec
components like microprocessors, when the manufacturers stopped make
them, to commercial grade surface mount parts. Mil-Spec is now
Mil-Perf, and the parts no longer need to be made a certain way, they
just have to meet performance limits. So companies purchase commercial
grade parts and test them and keep the ones that meet Mil-Perf specs and
they are now certified aircraft parts.

John