Stampe wrote:I dropped into County Fire at Rochester Airport this morning they are about to start selling the 1 kg extinguishers using the agent FE36 ( not 35 as previous) branded as Avi-Ex cost £170 nil VAT which includes a bracket suitable for light aircraft use.The governor there is a current PPL and the product is about a third of the current price of an equivalent BCF/Halon extinguisher.
I did a little internet research on FE36
and came across this:FE-36 and Hydrogen Fluoride
When combusted, under certain conditions, FE-36 can produce hydrogen fluoride (HF). Whilst this gas is generally produced in small quantities, and the gas itself boils just below room temperature, you should make sure that after a fire, the area is fully ventilated before staff return.
You should also avoid breathing in any fumes from an FE-36 extinguisher treated fire, as on contact with moisture, including human tissue, hydrogen fluoride converts to hydrofluoric acid. This acid is highly toxic and corrosive.
given the confined cockpit is this significant?
The smoke fumes, gases and fire in the cockpit are significant factor anyway and no doubt so is the discharge from a dry powder extinguisher which I've seen in many EASA and non-EASA aircraft.
It would seem that what ever we use there are downsides and these are probable less significant than the fire itself.