So, google says 13mtrs clearance , Navionics says 15.982mtr (52.4feet), then a blog I was reading said 16.5mtr, and my charts on OpenCPN say centre span 16mtr, with other spans at 15, 13 and 10mtrs respectively...
I'm presuming all at Mean High Tide....
However 13-16mtrs range means yes or no, anyone know the height of their rig, or actual clearance on XX tide?

The height is "above high water spring tides". The top of page 43 of the link below has 16.6m. It is a 2012 document and would be expected to be correct.

maritimemanagement.transport.nsw.gov.au/documents/boating-safety-plan-nov-12.pdf

The 2 links below suggest 16m and 16.6m.

www.scarlettsailing.net/SCARLETT/Frankly_my_dear.../Entries/2012/3/22_Day_323_-_And_were_bound_for_Botany_Bay!.html

www.mhyc.com.au/images/stories/compase%20rose/Compass_Rose_May_14_A4.pdf

We are 13.2m top of mast above the waterline and have never had a problem obviously. I scaled a J109 mast off a sailboatdata drawing and got 16.7m for that. So there would be some inaccuracies in that scaling. But I know that a J109 regularly passing under the bridge to race out in the bay and back to Kogarah Bay needs to keep an eye on extra high tides, and on at least one occasion over the years has had to get a bit of a heel on to clear the centre....................very rare obviously.

From the above evidence I would say 16.6m would be the number for the bridge clearance above high water spring tides.

If it helps, my air draft is 15.8 metres. The only times I go under the bridge are to haul out at Endeavour Marine. I wait for a low tide, and I scrape under. I would not try it at a top of tide.
There is a Bavaria 40 that now lives in Port Hacking, near my mooring, the previous owner clipped the mast to the top of the hounds, to clear that bridge.
cheers Richard

Stockie said..
If it helps, my air draft is 15.8 metres. The only times I go under the bridge are to haul out at Endeavour Marine. I wait for a low tide, and I scrape under. I would not try it at a top of tide.
There is a Bavaria 40 that now lives in Port Hacking, near my mooring, the previous owner clipped the mast to the top of the hounds, to clear that bridge.
cheers Richard

Ok good one, agree best to be safe. Sorry but for your text below what does that mean? That the previous owner of the Bavaria 40 shortened the mast from the around 7/8ths fractional rig to a masthead rig by cutting the whole mast off just above the hounds? A very drastic step to take by any measure. Realise slipways in the area are scarce, and Endeavour Marine Services are experts at everything they do. If it was me would sell and buy a shorter mast yacht...............

There is a Bavaria 40 that now lives in Port Hacking, near my mooring, the previous owner clipped the mast to the top of the hounds, to clear that bridge.

There are numerous Bavaria 40 models out there - if this is the one the mast height is 17.45m and so cutting it would obviously be needed.

www.boat-specs.com/sailing/sailboats/bavaria-yachts/bavaria-40-cruiser-farr-standard

If it is this model then scaling off the dwg gives mast height above dwl 15.4m. So no hacksawing needed.

sailboatdata.com/sailboat/bavaria-40-jj

Fully understand your gingerly approach with 15.8m - even with our 13.2m the bridge underside looks very close. Guess it is a visual impact of looking up a thin mast to the bridge underside. We have sailed under the middle span as well as the 2 next spans either side..........those 3 spans are the only ones yachts should sail under.