No one cares?
Rusty, Mel: Regarding ELT antennas:
IS an ELT required? Yes I think so, Part 91.
IS an ELT a TSO'ed item? Yes I think so.
IF you install a TSO'ed item you need to follow the TSO'ed / FAA approved instructions, right? (It is like a IFR GPS, it must be TSO'ed and installed per the TSO. The GPS and transponders are the only things for sure that need to be TSO'ed, Right?)
Just because we have gotten away with it does not mean it is right. Right?
-OR-
Right or wrong if we can get away with it than, Good Nuff.
Back to antennas:
One constant is almost every ELT instructions recommend that it be externally, vertically mounted (within so many degrees) on top of the plane.
The only reason to not follow the instruction is aesthetics and may be 1/8th MPH worth of drag. Good reasons for me, just like any RV'er. I have my own approach (rationalization).
Bottom line I don't care what you guys do, I don't want to get into who is right, I don't care. Also it is moot if you can get it approved. That is all that counts. However if I am going to be required to put something in, like an ELT, I am going to try to make it useful and reliable as possible, but each to their own method.
The Horizontal ELT antenna in the Vert/Horz stab intersection fairing works and should be safe if the coax does not get cut. You may end up nose down post crash. The antenna would be vertical. You can't always control the final crash position of your plane. Who knows what attitude the plane will end up after a cash.
Realistically with the hidden antenna, its broadcast directions will always be blocked by structure in a few directions, regardless of the final aircraft resting attitude, but even an "approve" external, vertical, on-top antenna location may be less than effective if the plane flips. So there you go, it does not matter?
I suppose if you survive and can get out, access the ELT you can always connect the external antenna.
I am not criticizing, just opening it up for discussion. Legal or not it is not a totally unreasonable thing to do (horz tail fairing antenna mount).
Not even Wichita can get it right:
I talk to Artex about this. The Tech Rep said even the manufacture of certified planes don't install ELT's correctly many times. The FAA buys off on them.
A few truths?
Allegedly an ELT (and antenna as well) is most likely to survive if mounted further aft, at least according to the manual. The rationalization that I use is if the crash is so bad that the cabin structure and equipment does not survive, than I won't either. So forward mounting, say in cabin/baggage area is acceptable to me.
Artex (makes stuff for high end aircraft) does study how ELT's don't work in real crashes. The instructions are born from this experience. OF course they thumb downed on my aft cabin mounting. However in a small plane the differnce between aft and far aft is not that great.
Granted our experimental aircraft ELT reliability record is probably not very well populated with data. Has anyone NOT been found because of a fwd mounted ELT or buried / hidden antenna? Doubt it.
The other common caution of TSO manuals is the coax should not run over long lengths thru differnt sections of the plane. Now that makes the most sense.
What to do?
In my RV-4 the antenna is under the canopy along side the roll bar (approved). The RV-7, the antenna is located just as if it was a EBC unit (the all in one units), just inside the canopy. If EBC can approve a cabin ELT antenna I assume I can, right? The ELT is right below under a cover with a short Coax run. If the cabin survives so will the antenna and ELT. Also my CG requires equipment not to be mounted too far aft. That is my story and I am sticking to it.
I am not saying the tail fairing is a bad place for the antenna. For me I want to mount the ELT forward and did not want a LONG coax run, so the tail antenna is not for me. The RV-7 tends to be tail heavy and did not want the ELT back there. That's my objection. With my cabin antenna location it is "vertical" and it is on the top (side) of the aircraft. Like I said EBC can do it, why not (besides the manufactures instructions).
One side note, if your antenna is in the tail and the ELT is way forward, say in the baggage area, you have a long coax run which can be cut. Again it is not who is right, but a realistic discussion on a "system" installation, pros and cons. We are big boys (and some girls but you know who you are), we can figure out what we want to do.
The most important thing is precedence, which has been set. We know we can throw the ELT and ELT antenna in any old way and no one will care. Cool. My plan "A" is not to crash.
George
PS I have seen many external ELT's on RV's myself, but admit most new builds have buried ELT's.
PSS the new 406 ELT's may never be mandated? The Gov does not have the cojones. However the 243.0MHz is scheduled to go away? We will see, but right now 406 is not a done deal for the time being. If I was going to fly in Alaska, Mexico, South America or go around the world, I would get a Personal 406MHz unit with internal GPS postion. They cost less the $800. I may get one anyway. They are great for boating, hiking, skiing or even driving. People get stuck in their cars every year, especially in the winter. I flew a lot on the west cost. I would go almost direct Redding CA, to Phoenix AZ. That takes you over the Sierra Nevada mountains. Same with the Cascades in the NW. People go down and are never found. They just found a WWII pilot recently. Will a 406 ELT save your life or even a standard 243/121.5 do it? Well if I survive I sure want to be found. Even people who crash less than a mile or so from a major Freeway are not found for days sometimes, it the ELT does not activate.
There was one tragic case from my old flight school club where I was a CFI. (link below see page 3/4 - 1b/1c) The survival aspects and ELT section are interesting. The ELT was damaged and did not work. The pilot survived the accident but died in part due to hypothermia. The plane was not far from a major interstate freeway (1.5 sm). Sadly they where not found for a day and both pilot and passenger expired by than. If the ELT went off, the pilot may(?) have survived if found in time? Also a factor was the installed ELT. The crash was clearly violent and clearly the ELT was damaged (just aft of the C172 baggage compartment on the right side wall like we install them many times). What if it was in the tail? My installation is to have it in the baggage area near the pilot/pass.
http://www.ntsb.gov/ntsb/GenPDF.asp?id=SEA94FA014&rpt=fa
