Audipilot1 Posted June 17, 2015 Report Posted June 17, 2015 My friend has a newer M20j ( I actually think it was the last produced before Mooney shut down) with an all glass panel and pretty fantastic avionics. On a trip yesterday he had his iPad plugged into the cigarette lighter and the charger caught fire with sparks flying everywhere. Fortunately he pulled out the plug before the situation got worse. The same thing occurred with his stratus charger. We now know what the issue was and are completely in shock. I'm curious if others have an idea what caused this? Quote
yvesg Posted June 17, 2015 Report Posted June 17, 2015 12 volts devices plugged into 24 volts outlet could cause this. Maybe this was the case? Yves Quote
shorrick mk2 Posted June 17, 2015 Report Posted June 17, 2015 Ipad cigarette lighte adapters should handle 12 and 24v equally well, but worth a check on the label before plugging it in :-) Quote
chrisk Posted June 17, 2015 Report Posted June 17, 2015 I'd guess something with the voltage regulator. Quote
Ftlausa Posted June 17, 2015 Report Posted June 17, 2015 This exact same thing happened to me as well a week ago while trying to charge an iPad in flight. I assumed it was just a bad charger plug that I was using for the first time. Very unnerving to have that electrical fire smell in the cockpit.  I wont be doing that again! Quote
N33GG Posted June 17, 2015 Report Posted June 17, 2015 The old cigarette lighter outlets have a resistor that prevents surge current until the lighter heats up and its resistance increases with temperature. If you are using an old cigarette lighter as a voltage supply, that resistor needs to be removed or the outlet replaced with a newer 12v supply outlet. (I don't know if yours has a cigarette lighter with the resistor or a 12v power outlet...if it had the old cigarette lighter plugged in it, it most likely had the resistor I am referring to)  Doesn't matter much at low currents, but at higher currents, that resistor is just accumulating heat, and it has to go somewhere. May or may not be related to the above problem, but maybe.....?  For your information pleasure, etc... Quote
jetdriven Posted June 17, 2015 Report Posted June 17, 2015 thats good info. I need to check mine come to think of it. FWIW I have been using 12v chargers for iPads for 4 years, no issues. Quote
N33GG Posted June 17, 2015 Report Posted June 17, 2015 thats good info. I need to check mine come to think of it. FWIW I have been using 12v chargers for iPads for 4 years, no issues.  They are only a problem when you see smoke... until then, no big deal! Quote
N33GG Posted June 17, 2015 Report Posted June 17, 2015 Probably not as much of a problem with older electronic/electric devices. Today, however, many devices have switching power supplies that can use a wide range of voltage input to operate. Only catch is, when the voltage goes down, the switch mode power supply asks for more current to meet the power demand. Therefore, when the voltage dropping (surge) resistor in the cigarette lighter drops the voltage due to current, the switch mode supply says just send me more please! More current equals more drop, and more heat, and the cycle continues. Not a good combination...  First thing I do when I get an older aircraft is make sure those resistors are not in my aircraft. They look like a miniature hockey puck about the diameter of a nickel/dime, and about a quarter inch thick. Usually, I just replace the lighter with a new 12v power receptacle. Quote
Loogie Posted June 17, 2015 Report Posted June 17, 2015 One better option is to carry a juice pack to supply extra power vs plugging to the a/c. Juice packs are slim, and can be stowed on a pocket to the left of the seat unobstrusively. These packs are approved by the FAA, and circumvent the power converter issues. They also don't generate RF noise like those charging plugs do. Just a suggestion. Quote
DonMuncy Posted June 17, 2015 Report Posted June 17, 2015 The wiring diagram for my 1982 231 does not show a resistor in the cigarette lighter plug. Do you think that is just an omission in the diagram, or it doesn't have one. Quote
JaredDavis Posted June 17, 2015 Report Posted June 17, 2015 Are we really playing a guessing game on a potential fire issue? Â Please tell us. Quote
N33GG Posted June 18, 2015 Report Posted June 18, 2015 The wiring diagram for my 1982 231 does not show a resistor in the cigarette lighter plug. Do you think that is just an omission in the diagram, or it doesn't have one. The resistor is integral to the receptacle...not a separate part. But it can be removed... Quote
N201MKTurbo Posted June 18, 2015 Report Posted June 18, 2015 Did the socket go up in smoke or the charger? Quote
Super Dave Posted June 18, 2015 Report Posted June 18, 2015 If your friend hasn't already made a report, you should let him know that in flight fire is one of the incidents that require immediate notification to the NTSB. Quote
Alan Fox Posted June 18, 2015 Report Posted June 18, 2015 I had no Idea that Mooney was producing J's when they shut down...... Quote
Audipilot1 Posted June 19, 2015 Author Report Posted June 19, 2015 Sorry folks for keeping you hanging. Busy day working. Turns out that the cigarette lighter was 20v just like the rest of the plane. The adaptor was 12v. The friend flying has over 20 years experience flying and was a bit shocked as am I that there was a plug in the plane for an adaptor and it wasn't 12v. Im not aware of any stratus or phone adapters that are 20v so I'm not sure what purpose the outlet even has. Moral of the story is everyone should be aware of the power output of their adaptor ports. Such a simple thing and oversight could have turned out much worse. Quote
Audipilot1 Posted June 19, 2015 Author Report Posted June 19, 2015 Correction 24v. Sorry folks for keeping you hanging. Busy day working. Turns out that the cigarette lighter was 20v just like the rest of the plane. The adaptor was 12v. The friend flying has over 20 years experience flying and was a bit shocked as am I that there was a plug in the plane for an adaptor and it wasn't 12v. Im not aware of any stratus or phone adapters that are 20v so I'm not sure what purpose the outlet even has. Moral of the story is everyone should be aware of the power output of their adaptor ports. Such a simple thing and oversight could have turned out much worse. Quote
JaredDavis Posted June 19, 2015 Report Posted June 19, 2015 My 65 C came with a Casco Cigar lighter with an attached fuse in a can. The fuse is shown in the circuit diagram. Â Is this the resistor you are talking about? Â Some newer sockets have a bimetalic bar that causes a dead short if the device gets too hot. Be careful. Quote
DonMuncy Posted June 19, 2015 Report Posted June 19, 2015 So what's the bottom line here. Do I need to check for/remove a resistor from the cigarette lighter plug on my 12v 231. the reason I'm asking is that I had a cheap 2-port USB adaptor in my cigarette lighter, which was not keeping an IPad charged, and then failed entirely. I bought a presumably better (higher amp) unit which I have not yet checked out completely. Ordinarily I keep my IPad plugged in it, but when flying with my CFI, I envisioned having two plugged in. Quote
jetdriven Posted June 19, 2015 Report Posted June 19, 2015 Read the label carefully before plugging a 12v charger into a 24 volt airplane. There's s lot of piece of crap knockoff Walgreens and gas station chargers out there. Amazon has lots of the things so get s name brand one and read the reviews. Like this one. It's been plugged into my BMW which has a hot cigarette lighter socket since last December. 2.1A twice. https://www.amazon.com/gp/aw/d/B00K8WA7QC/ref= My only complaint it it fits neatly flush with the panel it's hard to remove. The blue light is hellishly bright but a sharpie fixed that. Here's another that's similar http://www.amazon.com/gp/aw/d/B00VH84L5E/ref=mp_s_a_1_11?qid=1434679050&sr=8-11&pi=AC_SX110_SY165_QL70&keywords=24+volt+ipad+charger Quote
Alan Fox Posted June 19, 2015 Report Posted June 19, 2015 The adapter from stratus is dual voltage 24/14 ..... Quote
LANCECASPER Posted June 19, 2015 Report Posted June 19, 2015 I had no Idea that Mooney was producing J's when they shut down...... Â They weren't. The last medium body Mooneys (Allegro (J) Â or Encore (K) ) were produced in 1998. Then came the S model (Eagle) in 1999. Model Chronology.pdf Mooney Product_History_Chart.pdf Quote
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