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ELT mounting

Stewbronco

Well Known Member
looking for some examples of ELT mounting ?! Here in Canada needs to be accessible and manufacturers instructions say to aircraft structure not just skin . .....and a far aft as practicable .
Looking at baggage compartment? Would need to reinforce the floor ( NOT desirable because of possible damage with baggage....maybe on shelf ?? Any ideas. Thanks. Stew. Pictures would be great.
 
What I did

I don't have a picture handy, but I can give you my 2 cents. I mounted mine on some stiffeners attached to the converging longerons that become the elevator bellcrank mount. To access mine, the baggage rear bulkhead must be removed. via several screws. In hind sight, this makes inspection of batteries, or deactivation in the event of a "false trip" like I had, a PITA. Next time I have my baggage compartment out, I'm going to put a small access panel in it...wherever you choose, make sure you can get it out easily. I also have a 3.5 gallon smoke oil tank mounted back there, and I seldom remove it, as I can still toss 2 good sized soft bags on top of it when wife and I go off for a trip.
 
Possible Solution

You can make a shelf that extends from the floor rib to stringer as already mentioned. Reference pic by the elevator bellcrank. If you don't want to form something that thick, you could possibly order one from Vince at F1 aircraft. Best of luck.
 

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Nowhere to hide...

Stew,
Alot depends on which ELT you install.
I wanted mine accessible in case of quick post-crash egress to carry out for rescue, forward of the CG (150HP/wood prop) and in plain sight. I bought an ACK back in the day (1995) thats nearly identical to their current model.
https://www.pilotshop.com/catalog/a...MIrOTP3aet7QIViaeGCh1RiwvEEAQYDyABEgIGc_D_BwE
I mounted it forward of my battery compartment-turned forward baggage compartment as I hinged the top as an access panel. I mounted the antenna under the canopy behind my roll bar with the top secured by a Zip Tie to keep it stationary.
I wanted to keep the upper fuselage antenna-free and hid my Comm and transponder antennas inside the wingtips initially and on the belly between the gear legs after I installed my ER tip tanks.

In 25 years and nearly 2000 hours it's worked great and the best part: easy to check battery and test.
V/R
Smokey
:)
 
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looking for some examples of ELT mounting ?! Here in Canada needs to be accessible and manufacturers instructions say to aircraft structure not just skin . .....and a far aft as practicable .
Looking at baggage compartment? Would need to reinforce the floor ( NOT desirable because of possible damage with baggage....maybe on shelf ?? Any ideas. Thanks. Stew. Pictures would be great.

Hi Stew,

Are you saying it has to be accessible from the cockpit. Is this required with the remote panel that can activate the ELT from the instrument panel?
 
Adding to what was stated above; the manufacturer's installation instructions that I've read suggest locating the main device back in the emp to help with survivability. That said, it is your build and it's nice being able to take advantage of exp world liberties. I'm doing such by installing the associated antenna underneath the fiberglass emp fairing as many others have done. Let us know where your mind ends up and why. Best of luck.
 
ELT placement in a -4

I have an ACK that has ridden in the starboard forward area of the baggage compartment floor without problems for the 1200+ hours this -4 has flown. The floor was reinforced where it sits. There are several reasons I wanted it there: it is not a light unit and putting it as far forward as possible but out-of-the-way as well keeps the center of gravity forward. If it accidently trips and the panel unit won't shut it off, I want easy access. If I happen to land where and how I wasn't planning, I want easy access to carry it around with me. I can understand the reasoning for putting it way back in the tail as the survivable part of the aircraft. But if the only part of the airplane that survived is the tail, I'm probably not going to be too worried about a fast rescue. I think accessibility outweighs the survivability of the unit. My antennae sits on a mount along side the starboard area of the roll-over structure. It's the wire one and is not too obtrusive. My fuselage has an ELT HERE placard on the outside.........:)
 
The same ELT has lived on the baggage floor in my RV-6 since it was built in 1996. It still works when tested. Remember, they're designed to survive a crash, so you're not likely to seriously damage it loading and unloading the baggage compartment.
 
Some notes with a Canadian flavour...

1) Last month new regulations for ELT carriage were published in the Gazette with a phase-in period. If you are not planning to install a 406MHz ELT now then you likely are shortchanging yourself in the long run as they are now mandated in the CARs.

2) Survivability of the ELT is crucial. Accessibility is a secondary consideration and NOT mandated in the CARs.

3) Newer ELTs all feature a remote control panel to be mounted in the cockpit, thus meeting the requirement for flight crew control of the ELT. All 406MHz ELTs meet this requirement. The exception to the rule is the device made by EBC which "may" not require a remote control panel if the ELT is mounted within direct reach/view of the flight crew. Note this is the only 406MHz ELT of which I'm aware which provides any relief from the requirement for a remote control panel.

4) The new regulations coming into force mandate dual frequency ELTs, 406MHz and 121.5MHz. There is at least one ELT on the market, from Emerging Lifesaving Technologies, which does NOT feature the 121.5MHz homing signal. Under the regulations published in the Gazette this ELT will not meet the installation mandate.

5) From a structural point of view, the simple requirement is that the ELT be attached to primary structure reinforced in such a manner as to ensure that a load of 100lbs applied to the ELT will produce deflection of its mount of less than 0.1".

6) If installing an ELT way back in the empennage, give consideration to accessibility for maintenance. The installation of a reinforced access panel adjacent to the ELT is worth looking into.

7) Some builders get caught by installing the ELT early; by the time they call for their aircraft's final inspection the 12 or 24 month inspection clock has expired, or the battery life has expired. Don't forget to ensure these inspection / life limits are complied with prior to final inspection. Yes, I know, you might want to say that your initial 25 hour fly-off has to be conducted within 25nm of home base so technically an ELT is not required. But ask yourself... if you're flying a brand new airplane which might develop problems, why in heck wouldn't you want an ELT there to save your bacon in the event you have a really bad day? If it's installed it has to be up to date with respect to inspections and life-limited components.
 
looking for some examples of ELT mounting ?! Here in Canada needs to be accessible and manufacturers instructions say to aircraft structure not just skin . .....and a far aft as practicable .
Looking at baggage compartment? Would need to reinforce the floor ( NOT desirable because of possible damage with baggage....maybe on shelf ?? Any ideas. Thanks. Stew. Pictures would be great.

This is my ELT mount that I built for my RV8. The ELT mount is attached to two longerons, just behind the baggage compartment. The ELT can be accessible by removing the cover panel in the rear baggage compartment.
 

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Going to do something very similar

After looking at all the regs and recommendations....I am going with something very similar but a bit more accessible as it will be on the " wall " in the actual baggage compartment up fairly high This is more in compliance that any other solution I could come up with ......believe me I looked at everything suggested here but I believe this is fits the " letter and intent " of our recently changed regs
 
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Mounted mine in a 6A on the centre floor just in front of the F-606 and to the rear of the pitch servo, with the mounting bracket attached to the very solid centre longitudinal structure between the F-605 (baggage compartment rear bulkhead) and the F-606.
Bill Brooks,
Ottawa, Canada
 
I mounted mine between the pilots seat and the fuselage near the seat belt attach point. Easy to test, service and activate in an emergency. If it doesn't servive there neither will I.
 
Any access panel pictures

…To access mine, the baggage rear bulkhead must be removed. via several screws. In hind sight, this makes inspection of batteries, or deactivation in the event of a "false trip" like I had, a PITA. Next time I have my baggage compartment out, I'm going to put a small access panel in it...wherever you choose, make sure you can get it out easily. I also have a 3.5 gallon smoke oil tank mounted back there, and I seldom remove it, as I can still toss 2 good sized soft bags on top of it when wife and I go off for a trip.

I am mounting my ELT behind the baggage panel using the Vans mounting kit. I am thinking about a hinged access panel on the baggage panel of my RV7/9. Anybody have a picture of a similar access panel?
 
RV-8

Following the manufacturer's installation instruction to mount the ELT to the structure, as far aft as possible and accessible for maintenance, I used a thick instrument panel 0.063 cut-out to mount the ELT base and then that to angles riveted to the side longerons.
 

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Remember the structural deflection recommendation for 406MHz ELTs... It's an easy test to do.

An applied load of 100lbs should result in less than 0.1" deflection (movement) of the mounted ELT.

This is a really good and simple rule to follow, but remember the 100lb load should also be applied in the "pull" direction i.e. trying to pull the ELT off the sidewall of the fuselage, just as crash forces would do.
 
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