My XS is a Trike with the drains religiously installed as per Mod 33; utilising
2200mm of 8mm dia. tube from each outlet (large radius loops to prevent kinks
without using fittings). The drains are positioned to the rear behind the wing
root and protude from the skin; totally exposed, just waiting to be damaged.
Level measurements of the drain tubes in the static position gives a max. tube
C/L at 160mm above the tank oulet tube C/L. Altogether an unsatisfactory setup.
From each tank oulet the drain tubes pass under/through both port and
stbd. seat voids before looping back through the tunnel to the rear. On port and
stbd. drains respectively are connected the sight gauge and fuel return.
My mod. would be to intercept the existing drain tube through the
cockpit
floor and form the drain beneath each seat by cutting a 30mm hole through
the external skin (away from the cockpit module bonded areas); and bonding a GRP
top-hat section above the hole. The top-hat section would contain the CAV drain
mounted on a bonded-in tee piece. This would give a drain length of about
300mm and a max. tube C/L level of 20mm above tank drain outlet. The sight gauge
and fuel return would be connected to the vacant tee connection port and stbd.
respectively.
I've seen photographs of CAV drains connected directly to the tank drain
outlets - but don't recall if these were UK models.
I've attached a draft sketch section of proposal.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=424973#424973
Attachments:
http://forums.matronics.com//files/fuel_drain_draft_172.pdf
|