Admin Posted November 10, 2013 Share Posted November 10, 2013 Just a heads up to those iPad, and other electronic device users, that having an electronic device charging in your aircraft can be a very dangerous thing to be doing. When an iPad etc battery goes flat whilst flying perhaps it may be time to revert to those paper systems than to try and charge it. [parsehtml] Feed from Recreational Flying [/parsehtml] Link to comment Share on other sites More sharing options...
fly_tornado Posted November 10, 2013 Share Posted November 10, 2013 Put the risks in proportion, apple have sold 170 million ipads. Still more likely to get bitten by the plane or weather Link to comment Share on other sites More sharing options...
facthunter Posted November 10, 2013 Share Posted November 10, 2013 I have a response to that idea f t. There are enough UNKNOWN hazards in the air without taking an extra KNOWN one there with you. Eliminating risks is always a worthwhile aim and it is an essential approach to safe aviation as a philosophy Nev. 2 Link to comment Share on other sites More sharing options...
fly_tornado Posted November 10, 2013 Share Posted November 10, 2013 I would be more worried about your health considering that most GA and RA accidents are pilot error... Link to comment Share on other sites More sharing options...
facthunter Posted November 10, 2013 Share Posted November 10, 2013 Be worried (concerned) about ALL risks. Talking of "pilot error" is for newso's or the non aviation informed talkfest. Easy to blame a lot of things on. Nev Link to comment Share on other sites More sharing options...
fly_tornado Posted November 11, 2013 Share Posted November 11, 2013 I've not heard a single incident of an ipad exploding in a cockpit or anything like this leading to any sort of accident. If you think your ipad could explode when you are flying it could time to give flying away... Link to comment Share on other sites More sharing options...
facthunter Posted November 11, 2013 Share Posted November 11, 2013 You just don't get it F t. Nev Link to comment Share on other sites More sharing options...
Dafydd Llewellyn Posted November 11, 2013 Share Posted November 11, 2013 Regardless of the above gems of philosophy, to what extent is this likely to be related to the issue of using lithium batteries in aircraft that have permanent-magnet alternators (Jabiru, Rotax) which require the battery charge to be controlled by pulse width controllers - as per the article in the latest Sport Pilot? This form of battery voltage regulation essentially controls the battery charge state by chopping the alternator output into short pulses - but it does not control the maximum voltage of the pulses, and so can cause problems with lithium batteries. This looks to me to be very similar to the mode of operation of "switch mode" UPS chargers for things like Ipads. It seems that RF interference is a common problem when using "cigarette lighter" chargers to run an Ipad in a car; and it seems to me to be entirely possible that the operation of a "switch mode" UPS charger may well be the source of considerable RF noise. If so, then it seems entirely possible that this form of charger is in fact unsuitable for use with a lithium-battery device, in or out of an aircraft. I would like to be able to use lithium-battery devices such as Ipad and BadElf GPS in my aircraft, on ship's power. Having to re-charge them every night is not really practical for a cross-country flight that takes several days. So I'd like to know, firstly, what is the liklihood that the aircraft charging system voltage spikes can affect the output of the USB charger; and secondly, what is the liklihood that the USB charger itself is putting out voltage spikes that can lead to battery thermal runaway? C'mon you fellows, there's an issue here. What's the answer? Should we be buying Ferrite rings and winding the USB charger leads through them, or what? Link to comment Share on other sites More sharing options...
rankamateur Posted November 11, 2013 Share Posted November 11, 2013 A smoldering ipad on your lap would be one hell of a distraction to even the calmest pilot. The flare at the charging point trying to burn a hole in your trousers would get your attention too. Link to comment Share on other sites More sharing options...
Guest Andys@coffs Posted November 11, 2013 Share Posted November 11, 2013 I suspect its all a mute point in the longrun. Today you have a choice of paper maps or EFB, give it a year or two and I suspect you can have map data in any electronic format you like as long as it isn't paper...... The reality of the battery issue is that the IPAD has as LiPO Battery and LiPO batteries do this from time to time. If we were all realistic about reducing risks then any smartphone, or indeed any mobile phone manufactured in the last 5+ years then we'd leave that behind as well cause its the same chemistry in the battery and same likelihood of occurrence just a smaller pack and therefore smaller issue if it goes into thermal runaway. That said no matter how big the LiPO battery any thermal runaway is going to create some excitement!! If we are on the lookout for LiPO then get rid of your GPS's cause most of them will be LiPO as well. Next time I go up I might try slowing to 70kts and see if I can crack the door enough to dump a runaway device....might need it one day.....just like I might need to know how to manage my Lotto $m as well...... "I the flying pilot bestow this runaway thermal device on the tinder dry forest below....How magnanimous of me Andy Link to comment Share on other sites More sharing options...
Dafydd Llewellyn Posted November 11, 2013 Share Posted November 11, 2013 I suspect its all a mute point in the longrun. Today you have a choice of paper maps or EFB, give it a year or two and I suspect you can have map data in any electronic format you like as long as it isn't paper......The reality of the battery issue is that the IPAD has as LiPO Battery and LiPO batteries do this from time to time. If we were all realistic about reducing risks then any smartphone, or indeed any mobile phone manufactured in the last 5+ years then we'd leave that behind as well cause its the same chemistry in the battery and same likelihood of occurrence just a smaller pack and therefore smaller issue if it goes into thermal runaway. That said no matter how big the LiPO battery any thermal runaway is going to create some excitement!! If we are on the lookout for LiPO then get rid of your GPS's cause most of them will be LiPO as well. Next time I go up I might try slowing to 70kts and see if I can crack the door enough to dump a runaway device....might need it one day.....just like I might need to know how to manage my Lotto $m as well...... "I the flying pilot bestow this runaway thermal device on the tinder dry forest below....How magnanimous of me Andy My question is, WHY do LiPo batteries do this from time to time? Is it because we're being supplied by junk chargers that lack suitable suppression of the "spikes"? This is NOT rocket science; I suspect it's marketting of junk accessories for which there is no suitable standard. Could somebody with an oscilloscope please look at the output waveform of a few typical Ipad chargers? And would the rest of you please shut up until we get this answer? 1 1 Link to comment Share on other sites More sharing options...
facthunter Posted November 11, 2013 Share Posted November 11, 2013 When the Boeing Dreamliner is grounded for battery problems, what hope have WE got? Battery problems are not unknown in larger aircraft . Their condition(temp etc ) has to be monitored and you usually have access to the E&E compartment to get at them.. Using cigar lighter sockets and ODD alternators.( basically flywheel magneto's but low tension) with fairly ordinary diodes may not be up to the job. A lead acid battery holds voltage to a limit better than most other batteries, but still varies. Nev Link to comment Share on other sites More sharing options...
Captain Posted November 11, 2013 Share Posted November 11, 2013 And would the rest of you please shut up until we get this answer? No worries Daffydd. I am shutting up, as instructed, and will not post on this thread. Trust the rest of the plebs will do the same. 1 1 1 Link to comment Share on other sites More sharing options...
Dafydd Llewellyn Posted November 11, 2013 Share Posted November 11, 2013 OK. take a look at this: http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html Link to comment Share on other sites More sharing options...
Dafydd Llewellyn Posted November 11, 2013 Share Posted November 11, 2013 When the Boeing Dreamliner is grounded for battery problems, what hope have WE got? Battery problems are not unknown in larger aircraft . Their condition(temp etc ) has to be monitored and you usually have access to the E&E compartment to get at them.. Using cigar lighter sockets and ODD alternators.( basically flywheel magneto's but low tension) with fairly ordinary diodes may not be up to the job. A lead acid battery holds voltage to a limit better than most other batteries, but still varies. Nev Yep; I'll be using an Odyssey. That will handle the noisy alternator output, and I assume smooth it out, somewhat. However, it seems to me to possibly be a good idea to add some suppression on the avionics bus; it costs peanuts to obtain a ferrite ring & wrap the power lead through it a dozen or more times; and a power-factor correction capacitor for a 40 watt fluorescent lamp is neither heavy nor expensive. However, this is not my area of expertise. Obviously, it's important to supply cooling air to an Ipad or whatever, too. I suspect this issue is simply one of suitable installation design, and probably quite straightforward to deal with - but I'd like somebody with some expertise in this area to make some critical comments. Link to comment Share on other sites More sharing options...
Guest Andys@coffs Posted November 11, 2013 Share Posted November 11, 2013 110v-240v wall chargers are generally switchmode supplys and they can generate significant RF noise if the developer is frugal with design and or implementation of filtering circuitry. Agree that in poor design they can be lethal if you end up on the end of what you think is 5VDC but ends up being 240V AC However for car or aeroplane use the 12v to 5v charger we use is very unlikely to be switchmode and more likely to be a linear regulator such as the LM7805 which supply's 5v DC at up to 1.5A. So wont talk anymore about switchmodes they aren't going to be in the consumer cigarette plug pack. Whether the cigarette plug is a $2 ebay special or a $50 apple one the same LM7805 will be present (they cost only cents in bulk) and whether cheap or expensive aren't likely to vary significantly in the quality of the 5V supply. People need to understand that the actual LiPO charging circuitry is actually inside your consumer device, not in the cigarette charger. Why use LiPO....its cause the energy density is the highest commercially available and density translates to how long between charges. Why do they thermally runaway, cause its part and parcel of the LiPO chemistry/build and lesser density puts you commercially behind your competitors. No sane human will use LiPO as a replacement for an AGM lead acid battery, rather LiFEO4 is used. Thermally better but not best. Andy Link to comment Share on other sites More sharing options...
skeptic36 Posted November 11, 2013 Share Posted November 11, 2013 So, does making sure your device has a full charge before you leave, and therefore eliminating the need to charge inflight, solve this problem, or can they still ignite while discharging? Link to comment Share on other sites More sharing options...
Guest Andys@coffs Posted November 11, 2013 Share Posted November 11, 2013 Any abnormal current draw in excess of that specified can cause thermal runaway, in the same way that trying to put too much charge in too quickly can cause the same thing. Where would abnormal current draw come from...could be a failure of a component on the ipad system board as one possible source..... But its all about keeping things in perspective, buying a lotto ticket can lead to winning......but not for the majority. Choosing not to charge in the aircraft does remove 1 vector, but not all. Link to comment Share on other sites More sharing options...
fly_tornado Posted November 11, 2013 Share Posted November 11, 2013 So, does making sure your device has a full charge before you leave, and therefore eliminating the need to charge inflight, solve this problem, or can they still ignite while discharging? and replace the 1 in 100,000,000,000,000 chance of a faulty battery actually catching fire with the real possibility of the device going flat and either getting lost or running out of fuel? risk management techniques need some work... it might be time to hang up the goggles Link to comment Share on other sites More sharing options...
Ryanm Posted November 11, 2013 Share Posted November 11, 2013 and replace the 1 in 100,000,000,000,000 chance of a faulty battery actually catching fire with the real possibility of the device going flat and either getting lost or running out of fuel? risk management techniques need some work... it might be time to hang up the goggles One reason why it's not a bad idea to carry paper charts. Link to comment Share on other sites More sharing options...
DrZoos Posted November 11, 2013 Share Posted November 11, 2013 Just make sure your air bent is big enough to throw the ipad out of. Im putting in a mailbox slot just in case lol On the real side, this is the first reported case of an ipad fire. You need to be far more worried about your iphone. This case was the new ipad air, so i think its safe to assume all older ipads are pretty safe Link to comment Share on other sites More sharing options...
fly_tornado Posted November 11, 2013 Share Posted November 11, 2013 and people wonder why general aviation is declining Link to comment Share on other sites More sharing options...
Guest Maj Millard Posted November 11, 2013 Share Posted November 11, 2013 Just make sure your air bent is big enough to throw the ipad out of.Im putting in a mailbox slot just in case lol On the real side, this is the first reported case of an ipad fire. You need to be far more worried about your iphone. This case was the new ipad air, so i think its safe to assume all older ipads are pretty safe Or buy a Lightwing that you can safely open the door inflight on.......Maj.... Link to comment Share on other sites More sharing options...
Dafydd Llewellyn Posted November 11, 2013 Share Posted November 11, 2013 110v-240v wall chargers are generally switchmode supplys and they can generate significant RF noise if the developer is frugal with design and or implementation of filtering circuitry. Agree that in poor design they can be lethal if you end up on the end of what you think is 5VDC but ends up being 240V ACHowever for car or aeroplane use the 12v to 5v charger we use is very unlikely to be switchmode and more likely to be a linear regulator such as the LM7805 which supply's 5v DC at up to 1.5A. So wont talk anymore about switchmodes they aren't going to be in the consumer cigarette plug pack. Whether the cigarette plug is a $2 ebay special or a $50 apple one the same LM7805 will be present (they cost only cents in bulk) and whether cheap or expensive aren't likely to vary significantly in the quality of the 5V supply. People need to understand that the actual LiPO charging circuitry is actually inside your consumer device, not in the cigarette charger. Why use LiPO....its cause the energy density is the highest commercially available and density translates to how long between charges. Why do they thermally runaway, cause its part and parcel of the LiPO chemistry/build and lesser density puts you commercially behind your competitors. No sane human will use LiPO as a replacement for an AGM lead acid battery, rather LiFEO4 is used. Thermally better but not best. Andy OK, I'm looking at a Belkin micro adapter, which is so small there's barely room for the electrons. So I have no idea whether it's a transformer ("linear") type or a switch-mode type, I can't see how there's room for either. But if what you're saying is, it's unlikely that form of DC / DC step-down converter can produce much in the way of voltage spikes, the next question is, if it has a dirty input supply (as from the switch-mode voltage regulator of a permanent-magnet battery charge regulator), how effective is it likely to be in preventing voltage spikes from passing through it? And if it is effective, what happens to the resulting heat? The thing is so small there's hardly any heat dissipation capability there. Link to comment Share on other sites More sharing options...
jetjr Posted November 11, 2013 Share Posted November 11, 2013 Agree re dc converters, surely with the wide uptake of ipads in commercial use theres someone making isolated or high quality 12vdc power supplies......... Not a ciggy lighter type Narva do have hardwire USB port available but no idea whats inside. Link to comment Share on other sites More sharing options...
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