Interior Overhead Lights

[Mike A]

Twice in the past 3 years either I or a passenger has bumped the switch for the overhead interior lights in my 231 during the day and they were left on and killed the battery. I am thinking of having them disconnected at my annual next month but wanted to see if others have good ways to prevent it from happening on their birds. I’ve never actually used them to illuminate anything. 

[toto]

6 minutes ago, Mike A said:

Twice in the past 3 years either I or a passenger has bumped the switch for the overhead interior lights in my 231 during the day and they were left on and killed the battery. I am thinking of having them disconnected at my annual next month but wanted to see if others have good ways to prevent it from happening on their birds. I’ve never actually used them to illuminate anything. 

I don’t have a way to prevent it from happening, but after buying an expensive new battery in a similar incident, part of my “put the plane to bed” procedure now is to shut off the lights in the hangar, walk over to the plane, and peer in each side to make sure the damned lights haven’t been left on. 

[Mike A]

8 minutes ago, toto said:

I don’t have a way to prevent it from happening, but after buying an expensive new battery in a similar incident, part of my “put the plane to bed” procedure now is to shut off the lights in the hangar, walk over to the plane, and peer in each side to make sure the damned lights haven’t been left on. 

I like it but unfortunately both times have been broad daylight out on a ramp. 

[Niko182]

33 minutes ago, Mike A said:

I like it but unfortunately both times have been broad daylight out on a ramp. 

What about an switching it out with an LED. You could probably leave a tiny LED on for ages without having to worry about running the battery down.

[N201MKTurbo]

Take the Bulb out.

[PilotX]

47 minutes ago, N201MKTurbo said:

Take the Bulb out.

When I bought my Bravo there were no bulbs in the overhead. I think probably for that reason. There were some light scorch marks around some of them indicating that they probably been left on for a long time.

[LANCECASPER]

2 hours ago, Mike A said:

Twice in the past 3 years either I or a passenger has bumped the switch for the overhead interior lights in my 231 during the day and they were left on and killed the battery. I am thinking of having them disconnected at my annual next month but wanted to see if others have good ways to prevent it from happening on their birds. I’ve never actually used them to illuminate anything. 

@DonMuncy has a solution for this

[PT20J]

If you don’t have a clock that requires a keep alive from the ship’s battery, you can just remove the fuse near the battery marked CLOCK - it powers the lights.

Also, it would be very easy to move the power source to the battery bus so they go off with the master switch.

Skip

[DonMuncy]

Cmon guys. I developed an electronic timer for this very problem. I can give you schematics or I can build you one. It technically requires an A&P to install, but any semi-competent hangar elf can do it.

[Mike A]

7 hours ago, DonMuncy said:

Cmon guys. I developed an electronic timer for this very problem. I can give you schematics or I can build you one. It technically requires an A&P to install, but any semi-competent hangar elf can do it.

@DonMuncyDo you mind sending me the schematic?

[DonMuncy]

Mike,

Here is the schematic. Let me know if I can help.

[ZuluZulu]

On 10/24/2021 at 9:13 PM, DonMuncy said:

Cmon guys. I developed an electronic timer for this very problem. I can give you schematics or I can build you one. It technically requires an A&P to install, but any semi-competent hangar elf can do it.

Will this work with LEDs in the sockets?  I would love something that gives me more control over the lights, since the "low" and "high" settings no longer work.  It's either "on" or "off" with the LEDs installed.

[DonMuncy]

My timer should not affect the bulb situation. It would work the same way it does now, except about 10 to 12 minutes after shutting off the master switch, the cabin light will no longer have power to it.

[PT20J]

On 10/25/2021 at 4:09 PM, DonMuncy said:

Mike,

Here is the schematic. Let me know if I can help.

Don, I notice that the schematic shows the cabin light circuit connected through the master switch, so they will only work if the master is on. If you substitute the clock fuse for the master, they will work without the master switch on.

Also, if someone wants to change the length of time the lights stay on, it would be simple to adjust the time constant by changing the 47K resistor.

Skip

[N201MKTurbo]

3 minutes ago, PT20J said:

Don, I notice that the schematic shows the cabin light circuit connected through the master switch, so they will only work if the master is on. If you substitute the clock fuse for the master, they will work without the master switch on.

Also, if someone wants to change the length of time the lights stay on, it would be simple to adjust the time constant by changing the 47K resistor.

Skip

You can only turn it on with the master on, it will still stay on after the master is turned off. If you hooked it up to the clock fuse then it would still stay on after the master was turned off.

[N201MKTurbo]

On 10/25/2021 at 4:09 PM, DonMuncy said:

Mike,

Here is the schematic. Let me know if I can help.

I would probably use an MPSA14 instead of the 2N2222s

 

[PeteMc]

I was just going to Velcro a little cover over the switch after I hit it a few times putting the cover or something else into the baggage area.  Now days with all the 3D printers out there, someone should be able to make something that is a perfect fit.

I'm about to do the interior, so the plan is for LED lights and hopefully a recessed switch. 

 

[PT20J]

7 minutes ago, N201MKTurbo said:

You can only turn it on with the master on, it will still stay on after the master is turned off. If you hooked it up to the clock fuse then it would still stay on after the master was turned off.

I looked at it again and you are right. However, the problem with using the master switch is that you have to crawl into the airplane to get to it and the cabin light switches are just inside the baggage and main doors so that you can reach them without having to crawl into a dark airplane which is when I find them most useful.

Skip

[N201MKTurbo]

2 minutes ago, PT20J said:

I looked at it again and you are right. However, the problem with using the master switch is that you have to crawl into the airplane to get to it and the cabin light switches are just inside the baggage and main doors so that you can reach them without having to crawl into a dark airplane which is when I find them most useful.

Skip

You could put some kind of one shot to charge the cap, but then it would turn off even with the master on. And it would ruin the beauty of this super simple design.

[DonMuncy]

3 hours ago, PT20J said:

I looked at it again and you are right. However, the problem with using the master switch is that you have to crawl into the airplane to get to it and the cabin light switches are just inside the baggage and main doors so that you can reach them without having to crawl into a dark airplane which is when I find them most useful.

Skip

Because I virtually never start a flight at night, I have not had the problem. My problem happened when I came home after dark and needed the time to unload the plane.

[DonMuncy]

4 hours ago, N201MKTurbo said:

I would probably use an MPSA14 instead of the 2N2222s

 

You may be able to tell, I am only semi-electronically inclined. I used the transistors I had on hand. My (ignorant) guess is that a whole bunch of different ones would work.

Just out of curiosity, why would you use the ones you mentioned?

[N201MKTurbo]

1 hour ago, DonMuncy said:

You may be able to tell, I am only semi-electronically inclined. I used the transistors I had on hand. My (ignorant) guess is that a whole bunch of different ones would work.

Just out of curiosity, why would you use the ones you mentioned?

Oh, it is a Darlington, it would replace the two transistors. It would save you $0.25 and a couple of solder joints.

https://www.digikey.com/en/products/detail/onsemi/MPSA14/32395?utm_adgroup=Semiconductor Modules&utm_source=google&utm_medium=cpc&utm_campaign=Dynamic Search_EN_Product&utm_term=&utm_content=Semiconductor Modules&gclid=EAIaIQobChMIwKq7mobr8wIVuh-tBh2V5gBeEAAYASAAEgLkO_D_BwE

BTW, I think it is a wonderful circuit. KISS!

Edited October 27, 2021 by N201MKTurbo

[A64Pilot]

6 hours ago, PT20J said:

I looked at it again and you are right. However, the problem with using the master switch is that you have to crawl into the airplane to get to it and the cabin light switches are just inside the baggage and main doors so that you can reach them without having to crawl into a dark airplane which is when I find them most useful.

Skip

if the side window is open you can easily reach it through it, that’s how I get my headset out to fly the 140

[PT20J]

4 hours ago, DonMuncy said:

Because I virtually never start a flight at night, I have not had the problem. My problem happened when I came home after dark and needed the time to unload the plane.

Your hacks are legendary and very useful. I see that your design exactly meets your requirements. For me, about half of my night flights originate at night and so my desires are a bit different.

I used to leave the pilot’s window open until Don Maxwell told me that most of the tube corrosion damage he’s seen comes from that window. I replaced the seal and now keep it shut even in the hangar so I won’t develop a bad habit and  forget it when it’s parked  at some FBO’s ramp.

Skip

[jaylw314]

2 hours ago, PT20J said:

Your hacks are legendary and very useful. I see that your design exactly meets your requirements. For me, about half of my night flights originate at night and so my desires are a bit different.

I used to leave the pilot’s window open until Don Maxwell told me that most of the tube corrosion damage he’s seen comes from that window. I replaced the seal and now keep it shut even in the hangar so I won’t develop a bad habit and  forget it when it’s parked  at some FBO’s ramp.

Skip

Completely off topic, but I've always kept the pilot window closed even in the hangar because of spiders  There's like a never ending supply of them where we are...