WOW this got sarcastic
I appreciate the passion behind each persons opinion, but "can't we all get along".
So WHAT about ELT antenna location? Fact it's a TSO'ed item and comes w/ approved installation instructions, period end of story. Also its likely than an antenna mounted externally on top of the fuselage of a RV will fair a little better in transmitting (right side up or flipped) than say one hidden in the tail intersection fairing. THAT'S SUBJECT TO DEBATE OBVIOUSLY.
I can guarantee a RV plane sitting on its gear, with the ELT antenna mounted, vertical and external on the top of the fuselage will out perform alternative antenna installations (horizontal, hidden, cockpit), for this scenerio. By how much? Who knows. Of course how a RV comes to rest after am off field forced landing is unknown. I show a RV flipped and it still looks like the Vert stab will protect an external antenna. That does not discredit the others and that's the debate, are they good enough.
With that said, it's the installer that "certifies it", and that would be YOU. You get to make the decision. DAR could reject your ELT installation, but
hiding antennas inside the tail fairing or cockpit is an accepted practice. That does not mean its OK or not OK, but it's the reality, at least for experimentals.
The cockpit antenna has precedence with EBC ELT's with an integral antenna. A cockpit antenna with a bubble canopy does not seem too bad. An EBC-ELT in a Cessna with high wings and fuselage blocking the antenna is "approved"? I guess if you want to mount the antenna in the cockpit I guess the DAR can say "get an EBC ELT". We all can agree a little milliwatt VHF transmitter cannot get past metal. In my opinion a vertically mounted antenna in the cockpit may not be ideal but should work, but is there an ideal crash?
Of course the ELT takes on more importance if you like to fly over remote rugged regions (mountains, forested, remote unpopulated). Planning on how to survive a crash is important, but avoiding the accident is more important. For you fatalist don't bother.
Survival gear is must flying over remote areas (sleeping bag, water, etc) Also a detailed flight plan (fly exactly) is cheap insurance. In flight positon reports, even VFR is good. Cell phones or $700 PLB's with self contained GPS (personal locator beacon) are great. Australia is allowing PLB's instead of aviation ELTs. Hand held radio is also good. Most airline operators require crews to monitor 121.5. I hear 121.5 ELT's and report them to ATC once every year or 2. 121.5 is not totally useless.
Surviving a crash to die later has happened. Survive the crash and live, only to die from exposure and shock many days later is extra tragic. Before the famous 1972 loss of two congressmen in Alaska, in 1967, a mother and daughter survived a plane crashed in the Sierra Nevada's. They lived 54 days. The 16 year girl kept a diary and heard 59 airliners a day fly over them. Two years later a DC-3 crashed and 3 search planes where lost in the mountains, so California was the first to call for ELT's for aircraft based in state. It was made national law in 1974.
I know of one case personally. The flight school I CFI'ed for had a C172 go down in Oregon trying to shoot a non-precision approach. After a miss and another attempt, it hit a mountain, only 5 miles from the airport and a mile from a major interstate, which ran near the airport and crash site. The ELT did not go off.
The pilot walked away in shock and died a day later from exposure and shock. The passenger expired in the plane at some time. I'm not clear if she died immediately or later. Clearly a "save" was possible if the ELT worked. Even with radar it took too long to find. The crash was violent enough to rip the ELT from its mount. Unknown if pilot tried to recover or manually activate the ELT or if possible.
He was only a mile from a super busy freeway! I never flew with the accident pilot, but I knew the CFI who did his recent instrument comp check. She was very upset, as one would imagine. (note: this was before wide spread cell phones and GPS use. I'm sure a cell phone would have saved one or both. Those new PLB's could be a life saver.)
FOR THOSE WHO SAY ELT's NEVER OR RARELY WORK, consider the context. Granted, early ELT's where terriable and rushed into use after two congressman where lost in Alaska. Also, factory planes are NOT an example of GREAT installations. Factory plane where casual with installations instructions and they did not know better. Factory installations and early ELT's where horrible. WE CAN DO BETTER TODAY!
ELT's are like medical/auto insurance, just because you have it does not mean you want a car accident to collect on your policy. However if I'm going to have it (insurance or an ELT) I want it to work. Cheap insurance with lots of deductions does little good.
Do hidden antenna's or cockpit antenna's work? Who knows for sure. Lets find out! Probably will not change minds but would be nice to know.
Here's a picture of a RV flipped after loss of power on takeoff, later repaired and flown. Pilot/instructor walked away with just cuts and scrapes, but had to dig their way out through cracked canopy and marshy ground (hint get egress tools for survivalist, fatalist don't bother.) I penciled in possible antenna locations for grins & giggles. No comment or prefrence implied, JUST a visual to consider for entertainment purposes only. (cockpit, external top fuselage, wng-tip and inside tail intersection fairing
(ELT unit near antenna is critical. You should be able to access ELT unit after the accident of course. The tail location is hard to see, but I think it would have the least transmission range and omni-directionality. The external one is probably best by visual inspection. Who knows for sure?)
Here's my old RV-4 with antenna near roll bar. Likely a terriable RF radiation pattern from the physics of antenna design , but very common RV-4 set up. For the side-by RV's, like Robert Scott, I'm installing similarly but on passenger side.
It should be better than up against the roll bar as I had in the RV-4. The lack of "ground plane" and obviously blockage from fuselage are negatives, but hey its OK for the EBC.
It's vertical, protected and exposed on top "under glass". That's my story and sticking to it. The RV-7 needs weight as far forward as possible so the ELT unit goes on fwd baggage floor. ELT access and short antenna coax run are pluses. The negative, ELT damage from being exposed in the baggage area, but beefed up mount structure and protective cover should do.
I'm not recommending, just talking folks. Do what ever you like. I do think external top is best. A friend has an antenna analyzer and plan on checking the ELT's radiation pattern. YES you can do test ELT (with in 1st 5min of hr, 3 sweeps).
Have any of you with horizontal antennas in the tail determined how far it transmits and in which directions? Might be good to know? Not saying it will be bad. The Ham radio guys have antenna these spectrum analyzers. Another method would be use DF equip and have someone from a distance in different directions try to "find it", from the ground or airborne. I bet if we knew our installation was really compromised, even under ideal conditions, it might change our decisions? I'm going to test my cockpit antenna installation. If it failed miserably compared to an external one, I'd drill the hole and mount it outside. I'll let you all know. I'll leave you all with this question:
HOW GOOD (or bad) ARE OUR SPECIAL ELT INSTALLATIONS?