OK, seems there is somewhere from 36 to 47 tonnes annual use of lead in Oz avgas. For the exercise perhaps we can go worst case and use 47 tonnes.
What happens to it ? i guess it does its job and flows thru the engine and out to the atmosphere.
I see a comment on the lead accumulating in the engine oil. What percentage of the 47 tonnes of lead get changed out via the 25 hour oil changes. 5%, 20%, 50% ??? ...lets say two tonnes stay in the oil.
When the remaining 45 tonnes makes it out the exorst pipe, do this 'emitted' lead do the dust trick and float around for months at a time finnally settling somewhere mid Pacific ocean. Or do the heavy lead just fall to the ground in a matter of days ? Probably a bit of both.
Lets keep it a really bad worst case. Forty tonnes of lead gets put out over Oz. How bigs Oz... about 8,000,000 square kilometres. Where do avgas burning aircraft fly in Oz - from servicing remote Aboriginal communities to doing mail runs around regional centres to the local flying school. Just about every where. So its fairly evenly spread, though lead do accumulate, or so they say.
Now, i got straight F's in maths for the short time i were at school so yer better check me. Lets see, 45,000kg divided by eight million square km = .005625 Hmmm... bit hard to comprehend that amount over a square km, perhaps we need to work it to a square metre: .005625 divided by 1,000,000 =
Fleck ! me calculator caint work it out. Not enuf decimal place zero's.
...Anyway, there is an easier way to think about it. Next time yer open the box containing the latest wiz bang gadget from China - take a wiff, yer probably just got more lead inta yer in one go then a life time of sniffing avgas will do for ya.
Lead in avgas - Much ado about nothing...
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