Why are multiple engines different?

Mxsmanic wrote in
:

John Gaquin writes:

You know, Mx, now you're becoming argumentative (again). You can
play all you want at manipulating made-up numbers.

I'm not making things up.

You seem to be.

If engine reliability is constant, the
chances of a failure in a twin are higher than they are in a single.

Different engines have different failure probabilities.

In addition, the addition rule for probabilities is

P(A or B) = P(A) + P(B) - P(A and B)

You simply cannot assume that either one engine fails or the other and
not both at the same time.

Second, you cannot assume that the probability of a failure of an egine
on a single engine plane is the same as the probability of failure of a
different engine installed in different aircraft.

These probabilities come from engineering, testing, operation modes,
observed frequencies of failures etc. Proper maintenance or lack thereof
can also affect the probabilities. Thus, the antecedent of the statement
you make below

... if the engines are constant, then the chance
of an engine failure is always higher in the twin, but the chance of a
total loss of engine power in the twin is lower.


is false. Now you can go ahead and prove that 2 + 2 = 5.


Sinan

--
A. Sinan Unur
(remove .invalid and reverse each component for email address)