Wiring Question

[Bruce Fenstermacher]

Who uses their landing/taxi lights for only two minutes?

Gary, to answer your question, I only use my landing lights for two minutes or less. In fact I probably use them for less than a minute just as I touch down and intermittently while I taxi. And only on those rare occasions when I find myself flying my 170 at night.

Why do I do this? Because my charging/electrical system is not designed to keep them on continuously which is pretty obvious to me viewing the amp meter showing a large negative current with them on.

[bagarre]

I use my taxi light for collision avoidance but it's often pretty crowded down here in the SFRA.

I'd like to make it a habit of leaving it on all the time which is why I'm putting an LED in there.

[n3833v]

There are certain times I use my taxi light as collision avoidance and more than 2 minutes. Intermittant relays will burn out the coil if used too long due to the windings.

John

[hilltop170]

That's a clever install George.......................Edit: George- are those master relays you installed? Is it possible to snap a photo of them on your firewall, please?

I have not seen George's landing light relays so don't know if his firewall layout is exactly the same but the function is identical. Del Lehman at Mountain Airframe did both jobs. This is the best picture I have of the relays. It was taken in 2009, after George had his done.

IMG_2143_1.JPG

[spduffee]

That's a disgustingly nice engine compartment . Thank you for posting the photo of the relays.

[spduffee]

I spoke with my IA yesterday. His FAA Inspector is not willing to sign off on the alteration. He says the FAA is trying to reduce the amount of field approvals and wants to see more STCs. There wouldn't be any point in going to another IA because the folks at the Seattle FAA all sit in the same group and it would be discussed, I'm sure.
George and Richard, were yours done prior to 2005? He mentioned that year as being a turning point somehow. Anyway, we are going to submit it under some special approval process and see what comes of it. I am incorporating the wiring scheme into my 337 and I'll post the whole thing here when I am done, for whatever good that will do...geez.

[Bruce Fenstermacher]

Don't know who said what exactly but here is the way it really is.

The FAA inspectors job is to follow procedure. He is not allowed in many cases to approve alterations as he may have been in the past. This has nothing to do with the FAA not wanting to make these approvals but all to do with the FAA recognizing their inspectors don't know what they use to know.

And so a procedure to forward the request and required info up the chain presumably to the folks that still know what they should in order to approve such alterations has been developed. This is probably the "special approval process" you heard about. Nothing special about it, it is the process and it is the FAA inspectors job to assist you and your IA through the process.

Of course reality is this. Your IA has to work with this inspector and doesn't want to make waives. The FAA inspector can make his life miserable. He doesn't want to have the FAA inspector feel that he is making him do work he wouldn't have to if they just said no it can't be done. And many just say no.

Sounds like your IA is at least willing to work the system as it was designed.

[GAHorn]

I use my dual taxi lights continuously (several minutes while in the geographic area of an airport. T)e dual taxi lamp setup draws less power than the previous use of taxi/land combined....and the dual taxi lamps are more visible by others due to their being Fresnel lensed.)
I use my taxi lights on one mile final thru landing...and rollout, ...a couple minutes.
The AC is not regulatory as to operational use. (And wire gauge recommendations are based upon write bundles, not wires run in open bays such as leading edges. IE, theres a bit of wiggle room on such matters.)
My 200 watts of landing lamps are served by 10 gauge wire. My 120 watts of taxi lamps are served
by 14 gauge wire.
My installation (and Richards) were done in accordance with FAA-DER approved engineering which I paid for. The solenoids are mounted identically, and used the same materials list I supplied to the DER. The completed work was documented on Form 337, and required no further approval by any FAA inspector.