Cessna Caravan

[iandavid]

What is the inertial seperator for on the Caravan, what does it do?

[rayN5432H]

This is purely an educated guess, as I have not looked this up in a help file or other source (yet).

I suppose it is part of the deicing system. If I recall, when you turn it on, the deicing annunciator illuminates.

Additionally, being an "inertial separator," I guess it uses inertia (perhaps the centripetal force...well, maybe centrifugal force because centripetal is inward...of the prop - excuse my physics) to "throw" the ice off of...I guess it would be the prop that it is being deiced. After all, when the separator is engaged, the prop RPM drops.

That's about all I can come up with in my head for now. It may be completely inaccurate, so consider this disclaimer.

Ray

[rayN5432H]

"inertial separator:
Any dry type collector which utilizes the relatively greater inertia of par-ticles to effect their removal from a gas stream; e.g. cyclonic and impinge-ment separators, gravity settling chambers and high-velocity gas reversal chambers."

From IUPAC Compendium of Chemical Terminology 2nd Edition (1997)

****Here we go****
"Inertial Separator System: An inertial separator system in the engine air inlet duct prevents moisture particles from entering the compressor air inlet plenum when in bypass mode. The inertial separator consists of two movable vanes and a fixed airfoil which, during normal operation, route the inlet air through a gentle turn into the compressor air inlet plenum. When separation of moisture particles is desired, the vanes are positioned so that the inlet air is forced to execute a sharp turn in order to enter the inlet plenum. This sharp turn causes any moisture particles to separate from the inlet air and discharge overboard through the inertial separator outlet in the left side of the cowling.
"The T-handle is labeled "BYPASS-PULL" and "NORMAL-PUSH." The BYPASS position should be used when flying through visible moisture such as clouds, rain, snow, and ice crystals with an outside air temperature of 4° C or less. It may also be used for ground operations or takeoffs from dusty, sandy field conditions to minimize ingestion of foreign particles into the compressor. The NORMAL position is used for all other operations.

"Note: When moving the inertial separator control from the BYPASS to the NORMAL position during flight, reduction of engine power will reduce the control forces. Care should also be taken to avoid allowing the separator vanes to slam from one position to the other under the force of the airloads. Maintain a firm grip on the T-handle when operating the inertial separator."

From Cessna Grand Caravan notes, by Amer Khashoggi
http://www.najaco.com/aviation/caravan/operations/general.htm
How's that?

[jimmccarthy2]

A good (and very educated) guess Ray.

[j9_viper]

In short....the PT6 engine is sitting backwards in the plane....the separator is a door that opens in the inlet that will allow anything heavier than air to be ejected out the side of the cowling.