Aviation disaster waiting to happen

[Nesti (Mark)]

I received three new Lithium Polymer batteries yesterday to replace three suspect batteries for my electric gliders. These are 22.2V 4400mAh (That’s 60 sec @ 4000 Watts). They were sent by airfreight.

On the weekend I had a LiPol battery fire in one of my gliders. Luckily it was my biggest one so it has heaps of space, plenty of ram air for cooling and enough room to have separate battery power for critical controls well away from motor and battery heat. I got it down in one piece, but I lost my rudder servo and the secondary battery (NiCad) which runs secondary controls was crispy but still delivered power. Another 30sec and I would have lost the whole thing.

I’ve seen LiPols deliberately set alight on YouTube, but nothing like this…funny thing though, was that I was filming the flight from directly in front of the glider for a YouTube clip (as I’ve done before), but do you think it recorded properly…nope! It would have recorded everything and I would have had evidence. Damn!


My surprise in all of this is that LiPol batteries burn like you wouldn’t believe…I mean, when I pulled the canopy off to get the battery out, there was a ball of fire (and the worst smelling white smoke imaginable). I had to burry the battery in a hole and cover it with sand to put it out.

I tested the charge on the new batteries when they arrived, and they were about 85-95% full.

When you touch the wire contacts of this much potential difference, the wires weld together and stay connected (I’ve done it by mistake when soldering connectors onto the leads). What prevents this from occurring is just two pieces of heat-shrink…something that can easily be missing. Now I received 3 packs, imagine if I had ordered 10 or 20 packs and just one packs’ wires connected accidentally because the person sending them was not diligent …I don’t think it would extinguish in a hurry, especially if there’s a tonne of other burnable stuff in the container.

I still remember ValuJet lost an aircraft over Florida because of oxygen generator canisters were not shipped correctly.

I think sending these things by air isn’t such a good idea. Road freight takes only a few days more and is a little cheaper.

[erick (Eric)]

Nice

http://www.youtube.com/watch?v=wjmnVOjBjMk

Take care Mark - they look worrying!

Mark, was the fire caused by overheating of the battery due to a high rate of discharge?

[M_Lewis (Mark)]

Can you tell us more about what you were flying, as I fly very high performance gliders and UAV's. 6S lipo's sounds like F3D or F5D catagories, and many lipo's aren't rated for high burst C ratings.

What's the specs of the batteries and motor amps, watts etc?

Have you cut the wires to that lipo and put the entire battery immersed in salt water to totally neutralise it?

cheers

Mark

[gary]

Hi Mark,

Thanks for the post.

Originally Posted by Nesti

I think sending these things by air isn’t such a good idea. Road freight takes only a few days more and is a little cheaper.

You may not be aware that sending them by air was illegal.

The danger of them catching alight and bringing down an entire 747 somewhere
is specifically the reason why Australia Post has them on the Dangerous Goods
list. Lithium batteries and equipment containing lithium batteries will not be accepted
by Australia Post unless they meet very specific packaging requirements
and then only can be sent by road transport.

See page 44 -
http://www.auspost.com.au/Pdfs/DangerousGoodsGuide.pdf

As stated on page 45, "Australia Post cannot accept lithium batteries or devices
containing lithium batteries for international carriage of domestic air carriage".

IATA also have a guidance document on the transport of lithium batteries -
http://www.iata.org/nr/rdonlyres/480...tt_2009v21.pdf

The onus is on the individual who posts them to declare them to Australia
Post at the counter. They must be marked for "Road Transport Only", in red next to the address label.

The bottom line is that they should not have been put on board an aircraft.

It might be a message you might want to put out to others that share the same hobby.

[mithrandir (Andrew)]

Originally Posted by Nesti

I think sending these things by air isn’t such a good idea. Road freight takes only a few days more and is a little cheaper.

When Nokia recalled Li phone batteries, the shipping doco had in HUGE letters road freight only.

[erick (Eric)]

http://www.youtube.com/watch?v=MUoFjZAzGlw Duhhhhh!


http://www.youtube.com/watch?v=6M5ftkN9PtY How about we build these into electric cars?

[Nesti (Mark)]

Originally Posted by erick

Nice

http://www.youtube.com/watch?v=wjmnVOjBjMk

Take care Mark - they look worrying!

Mark, was the fire caused by overheating of the battery due to a high rate of discharge?

I attributed it to three factors;
1. The temperature on the day was 36degC.
2. The power output for my setup is 120Amps continuous.
3. Battery manufacturer (FlightPower), which has since recently closed its doors, had opted for a lesser manufacturer of the raw polymer material for their LiPol batteries.

[Nesti (Mark)]

Originally Posted by M_Lewis

Can you tell us more about what you were flying, as I fly very high performance gliders and UAV's. 6S lipo's sounds like F3D or F5D catagories, and many lipo's aren't rated for high burst C ratings.

What's the specs of the batteries and motor amps, watts etc?

Have you cut the wires to that lipo and put the entire battery immersed in salt water to totally neutralise it?

cheers

Mark

What gliders do you run??? as "Very High Performance" to me sounds like F3B / F3J. Or are you talking Hotliners etc?


Setup pic attached.

Sure, setup is as follows;
Motor: Hacker B50 7XL
Battery: FlightPower 6S 3700 30C [Rated to 111Amp (30C) Cont. 185 Burst (50C)]
ESC: Hacker 195 F5 (FAI)
Prop: 20 x 12 Full Carbon (Vita Prop)
Run times: Typically 1000ft in 16sec
Amps drawn: around 120-125Amps

This is essentially an entry level F5 type setup but de-tuned for longer run times to alt (Heavy glider). I run 6 cells to drop the Amps as 4 cells would be over 200 Amps...which means ESC burn-out.

Yeah, I had to kill 6 batteries in all...don't trust them.

Now using 35C cont and 60C burst batteries (6S 4400s !!!)

My point here though is simply that perhaps these things should be shipped by sea and road, rather than air.

[Nesti (Mark)]

Originally Posted by M_Lewis

Can you tell us more about what you were flying, as I fly very high performance gliders and UAV's. 6S lipo's sounds like F3D or F5D catagories, and many lipo's aren't rated for high burst C ratings.

BTW, building an Alex F5B (1.8m)
Hacker B50 5L (FAI motor), 4S 3700, 16x16 prop with 2.5 deg twist in spinner cross beam (16x18 ish).

[M_Lewis (Mark)]

Nice setups

I agree totally with upping the volts to get the amps down and the hacker B50 series is a solid motor. I run F3J, and converted a number of 'b's to electric with the cyclone elite series motors, spinning 22" props. The torque proved to be quite a handful on launch, as you couldn't launch over 25% throttle before you had enough airspeed to point it verticle, then watch it accelerate as it was going straight up. Such that we dont' allow these types of aircraft no longer at our local club's field, instead I have to go elsewhere to fly them with a bit more space and ceiling height.

[Nesti (Mark)]

Originally Posted by M_Lewis

Nice setups

I agree totally with upping the volts to get the amps down and the hacker B50 series is a solid motor. I run F3J, and converted a number of 'b's to electric with the cyclone elite series motors, spinning 22" props. The torque proved to be quite a handful on launch, as you couldn't launch over 25% throttle before you had enough airspeed to point it verticle, then watch it accelerate as it was going straight up. Such that we dont' allow these types of aircraft no longer at our local club's field, instead I have to go elsewhere to fly them with a bit more space and ceiling height.

We're getting off topic, but hey, this subject is really important.

22" props!!! must be 10-12" pitch yeah?

What F3J models were they?

Also fitting out a Electric Vladimir Supra with double carbon skin (the F3J comp one, but electric), warm to hot setup.

Have a Super AVA for lazy days too, R.E.S with warm setup.

BTW, F5B nationals was won on 2S!!!

[citivolus (Ric)]

I had some interesting conversations with Australia Post concerning the posting of Li-ion and LiPo batteries a few years back. They basically said "no way, under no circumstances, will we carry them", until I pointed out their own promotion of the Mobile Muster program. The envelope provided for posting the phone/battery is a standard non-padded poly satchel, not unlike the express post satchels. I'm still waiting to hear about a truck, plane, or distribution centre going up as a result.

For kicks, read their own address label. Don't skip section 4 of the dangerous goods declaration!!!

Edit: Might as well include Australia Post's somewhat naive response (names removed, of course):

Thankyou for replying to ***s email.

I would like to apologise for the misleading information *** has
provided you, I have followed this up to ensure correct information is
provided in future.

While some batteries are unable to be sent by through Australia Post,
i.e. wet cell batteries, dry cell batteries such as a mobile phone
battery are able to be sent as long as they are removed from the device
and are packaged in a way which will ensure they can not come in to
contact with, and thus complete, the circuit.

For a detailed explanation of this please follow the below link to our
Dangerous & Prohibited Goods & Packaging Post Guide, D10.2 page 44:

http://www.auspost.com.au/Pdfs/DangerousGoodsGuide.pdf

Once again please accept my apologies and should you have any further
enquiries which I may be of assistance with, please do not hesitate to
respond via reply email.

Kind regards,

*****
Domestic Resolutions Consultant
AUSTRALIA POST CUSTOMER CONTACT CENTRE
COMMERCIAL VIC/TAS DIVISION

PO BOX 5272 MOUNT WAVERLEY VIC 3149
T: 13 13 18 | F: +61 3 8847 9222

[Nesti (Mark)]

A few differences of information flying around.