New LED Lights

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Antoine
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Re: New LED Lights

Post by Antoine »

Thanks Steve. So it looks like we have another 2 + lbs to be saved.

It is interesting to compare the cost of such swaps with the alternative of having a part made of carbon fiber instead of glass fiber. It would take quite some area converted to carbon to save 2 lbs on a fiberglass part.

So far I have noted 4 reasonably expensive and legal weight saving measures:
- LED strobe lights
- LED landing/taxi lights
- Plane Power alternator
- MT or Hartzell composite prop

Any others I missed?
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trepine
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Re: New LED Lights

Post by trepine »

I just wish I could take 5 lbs out of the tail to fix the aft cg
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rwtucker
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Re: New LED Lights

Post by rwtucker »

I can't see a way to reduce weight enough to make a substantial difference in payload. All of the changes together are less than a gallon or two of fuel, which I never use anyway because it greatly exceeds the capacity of my bladder and/or my wife's patience. :(

I'm leaning more toward CG solutions. For the front, I have a heavier weight starter in mind, if this one ever goes, and maybe an Aux battery to run an inverter for the Tannis. For the aft, I drop the cargo netting when unneeded, no longer carry a bunch of tools I have never used, and ask rear passengers to stick their heads in the front passenger area for takeoff and landing maneuvers. Just kidding about the last one :D . . . but I have thought about it.

The only substantial solution I can see to both problems is the carbon fiber vertical stabilizer . . . but the price seems too high for the return and there would always be the nagging question about safety. Never want to lose my tail feathers.
Antoine
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Re: New LED Lights

Post by Antoine »

I just ordered a Plane Power alternator and the Orion 600 LED wingtip lights.
This should save 2.4 + 3.9 lbs and move CG aft.

If this were not a certified plane I would make a removable ballast part out of lead to compensate for that on the rare occasions it will be needed. (I suppose I'm not the only one who flies with no rear PAX most of the time.)

The ballast would be molded to fit under the NLG strut and held in place by a piece of sheet aluminum or GFC wrapped around the strut and fastened by 3 long bolts from side to side.
It would be a 5 minute job to install/remove the ballast as needed.
And it could be made visible enough that it cannot be missed during the preflight.
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rwtucker
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Re: New LED Lights

Post by rwtucker »

I like your thinking. If it can be quickly and easily removed . . .

20# would do nicely.
Antoine
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Re: New LED Lights

Post by Antoine »

After installing the Orion 600 LED wingtip units, I wanted to share some information about a "gotcha" and solution my A&P suggested,

The original installation uses an aluminum tube to protect the wires between the wingtip unit and the end of the winglet. This is probably lightning protection.
This tube is held firmly in place at each end. This shows the wingtip side. The tube has a "C" shaped extension soldered to it that is bolted to a ring clamp that catches a part of the Whelen light. The picture below shows the "C" shaped part coming out of the wingtip
photo 1.JPG

When removing the conventional Whelen unit, you lose the attachment at this point because the LED replacement has no provision for attaching the aluminum tube.

We reused the aluminum ring clamp, flattened it, bolted it to the "C" shaped part
photo 2.JPG
and then inserted it in place. Marked the bending point...
photo-8.JPG
... cut and bent it into an "L" shaped attachment part this is now caught between the Whelen LED unit and the wing tip. This gives mechanical stability to the tube and electrical continuity.

The Diamond SB says nothing about this matter. We did not think it was wise to interrupt the lightning protection circuit or let the tip of the tube hang and vibrate freely.
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mdieter
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Re: New LED Lights

Post by mdieter »

For better or worse, my mechanic and I decided to remove the alum tubes entirely. I believe they are RF (radio frequency) suppression for the high voltage pulses from the strobe power supply. I figured the tubes were unnecessary with the low voltage LED wiring. The mechanic used a couple of dollops of silicone to restrain the wires on the new installation.
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trepine
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Re: New LED Lights

Post by trepine »

When we did it, we removed the tubes, but also put in a grounding harnes they made to ground to the grounding plane in the wing.
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Chris B
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Re: New LED Lights

Post by Chris B »

mdieter wrote:For better or worse, my mechanic and I decided to remove the alum tubes entirely. I believe they are RF (radio frequency) suppression for the high voltage pulses from the strobe power supply. I figured the tubes were unnecessary with the low voltage LED wiring.
IMO the tubes are an essential part of the lightning protection! Sorry...

You also will not be able to pass the 1000 hr static bonding inspection without excellent grounding from the strobe to the main wing attachment. Trust me...

FWIW, I assumed that the big advantage of the Whelen Orion LEDs was being a 100% drop-in replacement. But after seeing Antoine's post, adapting the AeroLEDs Pulsar NSP lights seems very similar.
See this thread for details: link

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Antoine
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Re: New LED Lights

Post by Antoine »

Chris for some reason the Diamond OSB says nothing about grounding.
I find this very disturbing... And you are absolutely right about the static bonding issue.
But despite this issue, these units still look (to me) like a good drop in replacement. Physical attachment was real easy and the shape and fit are very nice. And any other unit will have the same problem.

Gilman: at least you will have done the static bond right, but I don't know to what extent the removal of the tube is OK certification-wise.

Mark if I were you I would reconsider this unless you are a VFR only pilot.
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