Certified v Uncertified

Hi All,

Can anyone tell what exactly is the difference between certified and uncertified aircraft engines ?.

Do certified engines have different (better quality) parts ?

Regards

Case

Hi,

Certified means tested to a design standard eg. 101.55

i.e. test run for various times at various loadings to strict

standards. Look 101.55 up (not the only standard) but the one most applicable to RAA.

Uncertified

does not mean substandard parts. All certified engines started as

uncertified at some point till testing and other paperwork requirements

were passed.

Your you beut certified engine rapidly becomes uncertified the second you change a plug or oil (in GA anyway and God help you if you do)

for our purposes it was certified, but to be brought back to certified

status it's off to the LAME with fistfulls of dollars. IFF they'll do

it.

It's actually a little more complex than that, I hope that helps somewhat

Micgrace

Thanks Michael,

That is clear enough.

regards

Case

Depending on the engine manufacturer, certified aircraft engines can

also be built to more exacting tolerances. Certified also equals

expensive. A good example of this is the Rotax 912 and Rotas 912A, with

the latter being the certified version and far more expensive. Aside

from price and paperwork the engines are 99% the same, however the

certified version is more likely to have been checked and re-checked.

It's a bit of a catch 22 however, because it's not like an engine might

be a little dodgey, so they just call that one a non-certified model,

it's more about processes, quality assurance, paperwork and liability.

Hope that muddles things for you enough.

Clem.

The processes are mainly the same if certified or uncertified. Mainly paying for the legal liability (plus testing etc) if certified. If uncertified you get to carry the liability not the company.

Due

to small production runs a manufacturer is hardly likely to have any

changes in production between uncertified/certified. This simply

doesn't make economic sense.

Micgrace