RowanBlossom wrote:Oh wow. I have always wanted to see what an older Hurricane looks like. Do you know why the square Hurricanes were taken out of production?
I believe that the original ACA Hurricane 130 (it was never officially called the MkI - that is a 'fan-name') was replaced by the Hurricane 130 MkII sometime around 1973.
I believe that the square horn design was less efficient at projecting sound, which is why it was changed to a round horn for the MkII.
The very first Hurricane 130 sirens supposedly came with a 10/12 port ratio. You can see an illustration of one in
this old ACA ad (I won't embed it, as many of us have seen it countless times already).
This was revised into the Hurricane 130 that you see pictured in this thread, and in
this manual. Notice the different rotator and the shorter chopper compartment when compared to the 130 pictured in the
old ad. This came with an 8/10 port ratio as standard, but was also available in 8/12, 10/12, 8/8, 10/10 and 12/12 configurations upon special request (as far as I know, none were ever ordered with anything other than the standard 8/10 configuration).
The Hurricane 130 MkII switched to the round horn design, as well as bringing numerous other improvements designed to reduce the amount of maintenance required. It featured a different blower, which required less maintenance, was designed to be mounted vertically (rather than horizontally like the original 130 and the Thunderbolt), and was rated at 30HP rather than 25HP. The MkII kept the same 8/10 port ratio as its predecessor, with the other configurations still available on special order. The rotator was also upgraded. See these pictures from
civildefensemuseum.com:
Horn 1,
Horn 2,
Horn 3,
Compressor & Boxes 1,
Compressor & Boxes 2. You can see the MkII manual
here.
I apologize if any of this information is incorrect.
RowanBlossom wrote:Also, how do you pronounce Allertor? The pronunciation of that particular siren has driven me nuts for some time now.
I agree with Andy - I pronounce it Alerter.
Regards,
Jerry.