T&T: Azimuth Drives

[2elnav at netbistro.com]

> Mike
>
> re: Azimuth Drives
>
> Many thanks for your response and had not thought of the fuel consumption
> differential. Input much appreciated. The hydraulic oil leak sounds a
> worry too. Perhaps these two more than counteract the benefits. I guess
>there is a reason why the conventional drive configuration has survived
so >long.

> Phillip Carr


REPLY
Another limitation  of azimuthing drives it the prop diameter limitation.
Because the azimuthing configuration requires a plate to be mounted in the
hull the "leg" lenght  is fixed. On a conventional straight shaft  and
inboard drive the hull itself becomes the only real limitation.

There is a company in Vancouver BC  that makes a brand called Olympic
Drives.  These have been in use since the late seventies that I know of.
thousands of them are in  daily use.  Power capability is  up to 200 HP.
This is plenty  for most of the trawles we normally doiscus that only run
at displacement speed. Unfortunately, these drives only come in one size.
Maximum prop diameter is limited to 27" diameter.  This is a bit small for
many of the trawlers  even in the under 50 foot size. 30" - 40" diameter
props is common and gives better efficiencies  than a 27" wheel would.