Re: FAA To Finally Ditch Floppy Disks & Win-95

On 6/18/25 10:15 AM, Rich wrote:

In comp.os.linux.misc c186282 <c186282@nnada.net> wrote:

On 6/17/25 2:20 PM, Charlie Gibbs wrote:

On 2025-06-17, c186282 <c186282@nnada.net> wrote:
>

On 6/16/25 1:52 PM, Charlie Gibbs wrote:
>

Yesterday I felt a something catching while moving the controls
in our small plane.  I found that various bits of plumbing
behind the panel had shifted to where they were touching things
they shouldn't.  Time to get out those good old nylon zap straps
and tie things back where they belong, just like the mechanics do.
Mind you, we don't get much above 10,000 feet...

>
     Always MANY failure modes alas ...
>
     However AIRLINE corps are SUPPOSED to keep abreast
     and ahead of these issues.

>
<cough>Boeing<cough>
>

     About the time I quit flying was during a huge OPEC
     oil embargo. Fuel prices quadrupled or more and too
     often you couldn't even GET the right fuel for the
     planes. Valve lock in a 4-cyl engine - NOT good.
     Green gas was NOT red gas !

>
And now it's replaced by blue gas - 100LL (low lead).
Much less lead than good old green gas (100/130), but
still three times as much as in the red gas (80/87)
that a lot of engines were designed for.  Beware of
lead fouling the plugs!

>
   In the 70s, engines made for Red did NOT take
   well to 100LL. It was both ignition and
   especially the VALVES. KEPT having valves
   stick ... NOT good. Besides, oil embargoes
   drove fuel prices through the roof - could
   NOT afford it then.

 Was 'red' a leaded fuel?  Tetraethyl lead as a gasoline additive
provided more than simply an octane boost.  The leftover residue from
combustion provided a lubricating effect, and as a result for many
(most?) engines designed in the days of leaded fuel the designers took
advantage of that lubricating effect from the tetraethyl lead for (at
least) the valve stems (esp.  the exhaust valve, which operated at
temperatures that made only oil lubrication difficult) and for
cushioning the valve seats when the valves closed.  When running
unleaded fuel in an engine that took advantage if the lead lubrication
effect, eventually one got stuck valves or very worn valve seats.

   You got that basically right. Red was leaded gasoline.
   The residues DID act as a lubricant. The burn rate was
   different from 100LL too. Aircraft engines are built
   more 'on the edge' than automobile engines because you
   have to keep the weight down and because of heat-
   management concerns.
   Unleaded gasoline was NEW at the time. There were SOME
   problems in SOME automobiles, but it was amplified in
   aircraft engines. Formulas have been adjusted since
   then, unleaded is ok now. The lead has been replaced
   with toluene and a few other things to push up the
   'octane rating'.