Gear Down Annunciator Bulb - Second Failure

[Jeff_S]

I noticed my Gear Down bulb had failed during the summer, so I had the shop replace it when it went in for some follow up work after the annual.  Now I notice it's burned out again.  So when something happens twice, I have to ask myself, coincidence?  It could just be a run of bad luck, but should I be looking for a more systematic problem that would cause this, such as a shorting wire? 

I'm curious what others have experienced.  Thanks!

[Boilermonkey]

A shorting wire would make the bulb flicker and could reduce the bulb life because that increases the number of hot/cold cycles (incandescent).  However, within a year...I'd say coincidence.   What's the bulb type?  You might look for a LED bulb with the same type listed and use that.  (I'm not an A&P, consult them for any "real" advice)

[toto]

Are you talking about the floor indicator, or the panel annunciator?

My floor indicator bulb had been burned out the whole time I've owned the plane. The shop noticed it last year at annual, and now that I have a functioning bulb, it's always surprising to look down and see it glowing. (The floor indicator works fine without a bulb, but it's obviously easier to see with one.)

While New Mooney is coming up with retrofit kit ideas, I'd love to see an all-LED bulb kit, maybe one for external and one for the cockpit. Incandescent bulbs never seem to last long in continuous-vibration environments, I guess because the little filament breaks loose. 

[bob865]

These are what I put in my plane during all of my upgrades.  Really bright!

Qty: 12 in Cool (Bright) White

https://www.aero-lites.com/product-page/aero-lites-aircraft-post-light-drop-in-led-replacement-for-ge-330-12-14vdc 

[ArtVandelay]

If the floor indicator, mine was broken. I ask my MSC to fix, it broke again. So I looked at it , they were cable tying the wire to the frame, resulting in the wire being stretched, so I cut that and secured it to the moving indicator...problem solved.


Tom

[toto]

2 hours ago, bob865 said:

These are what I put in my plane during all of my upgrades.  Really bright!

Qty: 12 in Cool (Bright) White

https://www.aero-lites.com/product-page/aero-lites-aircraft-post-light-drop-in-led-replacement-for-ge-330-12-14vdc 

Wow that's very cool. I didn't know these existed. 

Is there any regulatory problem with dropping in an LED replacement?

[Jeff_S]

5 hours ago, toto said:

Are you talking about the floor indicator, or the panel annunciator?

 

For me it's the panel indicator.  I've seen others replace with LED, so I may try to go that route. I assume there's a 28V version of the one someone linked above. 

[Boilermonkey]

Not an A&P.....  My view based on the countless discussions about bulbs.   If it has a cross-reference to what's in the parts manual you are fine as a PPL to replace it (LED or incandescent).  If there is not a cross-reference and it is not part of TOMATOES FLAME and the other "required equipment," you can replace as a PPL.  If it is part of required equipment and is not cross-referenced you need to find one that has a PMA/STC, or have your A&P approve and log as a minor alteration.  

[bob865]

3 hours ago, toto said:

Wow that's very cool. I didn't know these existed. 

Is there any regulatory problem with dropping in an LED replacement?

That's a deep and highly debated topic here on MooneySpace and the aviation world at large.  If I said my plane before, I meant my buddy's plane. And by my buddy's plane, I meant I heard he installed them.  I never actually saw them.  He probably took them out and installed only certified bulbs in his or her certified Mooney, erm I mean Cessna.

With that said, if you follow the regs to the letter then no,  you can't use them without some documentation and/or approval (see @Boilermonkey's post above).  If you have some common sense and realize that if an inspector wants to ramp check and fine you, he won't have any trouble finding something without looking at the lightbulb buried in your panel.  So an LED lightbulb that is good enough for the experimental market but somehow not good enough for the certified market is the least of your worries when the FAA's around.  You can see how one might be persuaded to go for it like my buddy may or may not have done.  

 

[toto]

Didn't mean to open a can of worms here. I just haven't seen these LED replacements for post lights before and was curious whether there is a standard paperwork approach. 

I've read all of the previous threads on landing lights, and I find Bertorelli's logic sound.

I'll back quietly away from the "regulatory" comment

[PT20J]

I tried the LED post and glare shield lights. The problem for me is that I like to keep the cockpit pretty dim at night and the LEDs don't dim nearly as much as the incandescents. Really, you need to change the dimmer type from current control to pulse width modulated.  There are PWM STC dimmers available, but that's more work than I wanted to go to for the few hours a year I fly at night. I'll save that for when I do a major avionics upgrade someday.

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