A number of subjects there.
Firstly the non-return valve. Actually, the PFA questioned why I had NOT got
one fitted in the case of the fuel injection system that I had fitted
previously (which circulated fuel back to the tank at a similar rate to the
914 system).
As a poor-man's alternative, I now have the 912 return-line restrictor
located just behind the firewall (because there is a joint in the return
line there and because it creates more unrestricted vapour headspace in the
top of the return line); so, if the return line is severed at a point
forward of the firewall, the restrictor provides at least some restriction
to backflow from the tank; LAA know about this and approved the
installation.
About fire suppression systems: a suggestion to the PFA some years ago to
include a port in the instrument panel and connected to a pipe leading to
the undercowl space (with suitable check valve) in to which a handheld fire
extinguisher could be discharged, met with a positive response. Albeit for
some reason unknown to me, such fire systems have been outlawed on rally
cars.
Regarding the RV that flipped on to its back at Fishburn recently, the pilot
commented that he would have preferred to have had a small 2lb axe to have
been able to get out. It was the rescuers that enabled exit through the
broken canopy. He considered that the small "lifesaver" hammers were a
complete waste of time.
Duncan McF.
----- Original Message -----
From: "Robert C Harrison" <ptag.dev@tiscali.co.uk>
Sent: Wednesday, September 03, 2008 6:26 PM
Subject: RE: Europa-List: Jos Okhuisen
> <ptag.dev@tiscali.co.uk>
>
> Hi! Frans/all
> As a novice I agree with your suggestion on the "check valve" in the
> return line and your impact theory for rubber pipes but the latter item
> would be marginal either way IMHO. The main thing is to apply the
> maximum delay of fuel spreading to the likely fire source at the front
> or under you and an element of chance would apply to either type of
> pipe. This is what has prompted me/many to replace the glass filters
> under the seat for Andair in the fuselage away from the pilot and /or
> have a different sight gauge to one encircling the pilot.
> All such things have to be weight considered otherwise an automatic
> extinguisher system with heavy tankage to supply but I'm sure you don't
> need me to remark on that.
> Regards
> Bob Harrison G-PTAG
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of Frans
> Veldman
> Sent: 03 September 2008 16:52
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Jos Okhuisen
>
> <frans@paardnatuurlijk.nl>
>
> Hi Jos and all,
>
>> Hi Frans and all, The silence is the normal waiting for the
>> investigation to come to a conclusion.
>
> Ok, I understand that. It is just that a few days ago you wrote that you
> were going to post more detailed information the next day, but I never
> saw it, so I wondered what happened. Glad that you are still ok.
>
>> Now a thick branch wiped the right side of the cockpit off, breaking
>> the fuel return alu tube.
>
> Ok, two toughts about that:
>
> 1) The fuel return line is obviously a risk, as it can not be closed
> with the fuel valve, and once broken it allows the tank to drain
> completely. I just realised that this risk can be minimised by putting a
> check-valve (one way valve) in the return line. So fuel can go TO the
> tank, but never FROM the tank. Has anyone ever considered this? I think
> I'm going to put this into my fuel system, unless someone can tell me
> why it is not a good idea to do so.
>
> 2) I have seen that many builders do away with the rubber hoses and use
> aluminium. Maybe the risk is higher with aluminium, since these tubes
> breaks easily, whereas rubber hoses just give way to impacts.
>
> Frans
>
>
>
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