----- Original Message -----

From: REHBINC

To: lml@lancaironline.net

Sent: Thursday, January 14, 2010 8:01 AM

Subject: [LML] Re: In Flight Engine Fire Extinguishers

CO2 would be just as ineffective in the cowling as Halon. Dry Chemical will tend to stick (somewhat) to the surfaces it encounters. It will especially stick to wetted surfaces; i.e.; fuel and oil. The biggest weakness I see with dry chemical is that it will be difficult to get it distributed to all of the surfaces under cowl.

 

This is a difficult area to adequately protect.

 

In race cars, we used to use Halon under hood and in the cockpit. It was good to get the fire down for half a minute or so to give the driver time to get his belts released and crawl out or the track crew to get there with additional capabilities. There was never any guarantee that the Halon system would fully extinguish the fire, it might or might not, but it would buy some time.

 

In a turbojet application, I suspect there is MUCH less airflow between the nacelle and the engine. (Not educated here, just rationalizing) In this instance, Halon would have longer residence time in the fire area and could make sense.

 

Rob

 

In a message dated 01/13/10 16:08:36 Eastern Standard Time, colyncase@earthlink.net writes:

Rob,

 

How does c02 or chemical stay on the affected area? 

Seems like airflow near the engine is going to be high enough to move just about anything off....am I wrong?

 

Colyn