I contributed a brief post the other day to the 'Holiday Homes Australia For Sale' group on Facebook. One of the readers, Danny, made the comment that someone living in my place would potentially face a "long walk to Magnums". Magnums for the uninitiated is a popular restaurant/bar in the main street of Airlie Beach, QLD, Australia, and which is visible from my home.
I flippantly replied that "a zipline might be do-able". But on further consideration ... would it?
The extent of vertical drop needed for a zipline to function is said to be no less than 3% - 6% (refer https://www.ziplinegear.com/blogs/engineering-and-design/the-beginners-guide-to-zip-line-slope-and-sag#:~:text=The%20slope%20of%20a%20zip,to%206%20feet%20in%20elevation). To reach this goal, the hopping-off platform at Magnums would need to be no higher than 3.45 m to 6.9m above sea level.
The height of my house above sea level is approximately 115m (at ground level)
The height of Magnums Bar is (say) 5m (at ground level & estimate only)
The distance between these two places (as the crow flies) is approx. 2.17 kms
As a consequence I would suggest that a zip-line might in fact be "do-able" if not for the existence of power poles and other pre-existing structures situated between Magnums and Boathaven Bay.
If an engineer happens to read this post, would you mind please running your eyes over these figures and letting us know how reliable they are?
Oh, and there was one another thing that crossed my mind. Should a tsunami hit the coast whilst someone was riding the zipline, how close would they get to Magnums before becoming submerged?
By way of background, the tallest recorded tsunami wave in Australian history was 7.9m (refer https://link.springer.com/article/10.1007/s11069-011-9953-y).
(NB: This proposal would be subject to local government and body corporate approval)