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ELT Antennae location

dave4754

Well Known Member
I have agonized over this for months and finally decided to install the Rami 200 elt antennae, it will service a Kinnad Compact ELT.

What are your thoughts on this installation

https://1drv.ms/f/s!Apov9vtfo19vyQRzashmQQ0FsTjO

It is placed just behind the passenger seat and tucked in behind the roll bar post on the shelf on top of the flaps There is no impediment to the flaps and the wiring is safely secured with zip ties and fasteners behind the panel.

I have one of those Commant 200 VHF/GPS antennae on top already and really didnt want to have anymore drag up there.

The signal should go through the plex, I will test this when i get the Kannad recertified.

Any thoughts?
 
My Kannad is in the baggage area also, the antenna is there too, the new 406 has a built in GPS antenna also so I wanted it to have a clear view of the sky, won't help it I end up upside down, but, I have a spare com antenna lead I can hook up in that case :rolleyes:
 
Dave,

My Ack 04 antenna is in a similar position. Mounted to a flange riveted to the top fuse longeron. The antenna is bent in a slight curve so it doesn't touch the plexi.

Bevan
 
Mine is in the same location but slightly further aft. Since I have a slider, I was able to drill a hole in the turtle deck support bracket and put the tip of the antenna through the hole (barely visible in the photo).

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There is a school of thought that believes a crash may cause the plane in an upside down position (specially for a RVx-A) and in such cases the chance of ELT antennae will be in an upside down and not as good for transmitting.

I have mounted mine in the tail portion under the fiberglass cover. I am not saying that it is a better place or worse, only that I thought it has a better chance of survival in a damage.
 
Regardless of where the antenna is, give thought to making sure the ant cable survives the crash as well. Routing it well dressed through multiple bulkheads is probably not a good idea.
 
Thanks all

Not sure if my photos got through i am using the One Drive and it appears it might be asking for passwords, if so my apologies.

I am hoping that any crash will be controlled and flown to the last breath of air under her wings which should leave us upright. That being said the antennae is nearly exactly upright and pointed through the plexiglass.

I was once Air Deputy in CASARA here in Canada and I know how frustrating it can be to try finding a weak signal. The ELT has the facility to advise of impact on 406 MHZ and help SAR techs to find it with 121.5 MHZ locaters.

Lets hope two things:
1/ We NEVER have to use it
2/ It is in the right place for the best signal

Thanks again all it sure is great to have this forum to bounce things like this off people.

Dave
 
On the 406, how long till the signal gets broadcast if the manual switch is activated on the panel? Is there a delay or instant? My plan should I ever need it is, if ditching in a remote area is to activate the ELT just before.......remote landing-tree branch trimming. So how soon before impact? 30 sec, 90 sec?
 
ELT activation

i dont know how this KAnnad works but when we used them in Search and Rescue work when the switch was armed it went off right away.

I cant see why that wouldnt still be the case.
 
Regardless of where the antenna is, give thought to making sure the ant cable survives the crash as well. Routing it well dressed through multiple bulkheads is probably not a good idea.

Good idea. My cable goes through one bulkhead, but I used an oversized bushing and coiled the excess cable together with Velcro straps, so hopefully it'll pay out in a crash and remain intact.
 
On the 406, how long till the signal gets broadcast if the manual switch is activated on the panel? Is there a delay or instant? My plan should I ever need it is, if ditching in a remote area is to activate the ELT just before.......remote landing-tree branch trimming. So how soon before impact? 30 sec, 90 sec?
Bret,
I believe it is immediate as I have used this option/switch during my annual test and I hear the ELT right away. For the same reason as you have stated, I have installed my control switch in the front of me (left seat) and it is part of my emergency list to flip it on if a crash seem to be imminent. I probably won't wait till 30 sec before impact though
 
Correct me if this is incorrect, With the Kannad Integra, the 121.5 will start to transmit and sweep instantly but the 406 will not transmit until 50 seconds after?
 
On the 406, how long till the signal gets broadcast if the manual switch is activated on the panel? Is there a delay or instant? My plan should I ever need it is, if ditching in a remote area is to activate the ELT just before.......remote landing-tree branch trimming. So how soon before impact? 30 sec, 90 sec?

Brett,
I am going through PPL training now, and my CFI explicity has in our emergency landing checklist to arm and fire the ELT when the decision is made to do a forced landing, even if that decision is at 10k feet. Fire it off, communicate to ATC or someone where you are going. This way the GPS coordinates get transmitted from a high altitude all the way to the landing, because once you "land" you don't know if the ELT will survive and be in a position that it can transmit successfully.
 
A buddy with Ham radio experience once told me that about a 6" diameter ground plane was reasonable for a 406 ELT antenna with reasonable broadcast results. He (tip up 7) attached a plate approximately that size behind his roll over structure & curved the whip up inside the rear plexi. I have done similar a bit farther back on sliders.

Re: broadcast activation, the 406 ELT will start broadcasting immediately on 121.5 (mainly useless in remote areas), after 50 seconds the 406 broadcast will commence which is monitored and will pinpoint your location for search & rescue.
121.5 is useful later when search & rescue are close and can vector in on that signal.

Re: activation in flight prior to eminent emergency landing - the sooner the better. 50 seconds is a long time to hang in the air.
 
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