Aircraft Engine Blog

On Sat, 1 Dec 2007 09:03:04 -0800 (PST), wrote:

What did you understand Kas to mean by his use of the term "lean misfire"?

He wrote, about that term, "...but I think most people understand what the
term means."

Maybe he defines that somewhere -- but someone who writes about a
technical matter and throws out a term and states "I think most people
knows what that means" are writing at a technically unacceptable
level.


I think the problem goes beyond that.

Here is a "dictionary" definition:

LEAN MISFIRE
A condition caused by an air/fuel mixture that is too lean to sustain
combustion. Lean misfire causes one or more cylinders to pass unburned fuel
into the exhaust system causing a big increase in hydrocarbon (HC)
emissions.

Kaz writes that "lean misfire" is the cause of the rough running engine
that results as you progressively lean an aircraft engine (at least for
some engines).

Instrumented test benches have not shown this to be the case.
--ron