by FlyerChief » Mon Jan 15, 2018 11:35 am
Hi Pete,
If I had to redo mine, I would likely just drill a hole near the top-center of the rear cargo bulkhead and mount the antenna pointing into the fuselage behind it, keeping the tip end as clear of metal tubing and bracing as possible. KISS principle.
Since the ELT antenna is only used in a crash situation there are a few considerations:
- It must be mounted securely and survive a very high G impact (both ELT and antenna)
- It must be serviceable, so access is important
- Many crashes involve the aircraft ending up nose down or inverted, so the antenna should be placed accordingly
By mounting it on the rear bulkhead pointing it down into the tail of the plane you satisfy most if not all of these issues. It does place the wire (or at least part of it) for the ELT antenna inside the cargo area so it would have to be protected from damage or disconnection when loading cargo.
In my Highlander, I have a Lithium Iron Phosphate battery on the firewall, so I used the plate designed for the battery to mount my ELT transmitter on. I have a small hinged access door on the rear cargo bulkhead, which allows me easy access to the ELT, rather than having to access it through the tiny triangular shaped hole in the tail of the aircraft. Keep in mind when you mount the ELT it needs to be able to survive a High G crash and easily removable to service it with battery changes every 4-5 years and possibly, annual re-certification. (depending upon local regulations)
I hope you figure out a solution that works well for you and your Highlander!
Dan
When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. ~Henry Ford