ACA Cyclone

The ACA Cyclone was an electro-mechanical, omnidirectional, dual-tone outdoor warning siren produced from 1968 to 2007 by Alerting Communicators of America (ACA). Originally intended for civil defense purposes, early versions of the Cyclone were rated at 120dB from 100ft, and later models were rated at 125dB.

History

The ACA Cyclone was designed by James E. Biersach of Alerting Communicators of America and presented at a Civil Defense convention in November 1968. It was originally rated at 120dB at 100 feet, but was eventually redesigned to the point of reaching 125dB at 100 feet. It utilizes a 40 HP motor (120) or 50 HP motor (125) due to the drag-heavy rotor design. The rotor consists of a "double intake" design, which is believed to have been inspired by Federal's 500 SH-TT siren rotor.

Cyclone siren rotor

The first version, the 1968 Cyclone 120, had both rows of ports angled downwards. Like some of the other 1968 ACA siren designs, it was changed shortly after to improve performance. These improvements included a new, simple intake, and most notably the top row of ports being straightened out, as to direct the low tone outwards for maximum range while projecting the high tone downwards to the immediate area. At some point afterwards we also saw the use of the long, curved intake as seen on their 3 signal sirens. This allowed for an optional coding damper to be added, which produced a pulsating "local code" tone.

In 1979, ACA was experimenting with the design of the Cyclone 120 to try and get the best performance possible. This included a slightly re-designed top cover, and a ring placed around the bottom of the stator to direct the sound outwards more smoothly. In 1980, this design was scrapped, and ACA unveiled the Cyclone 125, which came fitted with a new intake, a sound dispersion cone in the intake, and most notably a parallel stator, projecting both the high tone and low tone outwards. This was further assisted by a lip or "ring" added to the top cover of the siren. At this time, ACA unveiled the Penetrator-50, a 135dB rotating siren which replaced the Hurricane 130. The P-50 reused the rotor and stator of the Cyclone 120, and was produced alongside the Cyclone 125 until the early 2000s when both sirens were discontinued in favor of more modern sirens.

Technical information

Years	Type	Motor HP	Rotor/Stator interval	Notes
1968–1970	Cyclone 120	40 HP	8-12 port	Stator with angled bottom-row ports
1970–1980	Cyclone 120	40, 50 HP	8-12 port	Stator with angled bottom-row ports, larger intake. Allowed for a 3-signal coding mechanism
1980-1995	Cyclone 125	50 HP	8-12 port	Parallel stator, Redesigned Intake, later in 1990's Skirted Option was available using Banshee bottom Skirt
1995-2007	OM-125-AC / C-125-AC	50 HP	8-12 port	Parallel Stator, Redesigned Intake, Skirted versions now using OM-120 Bottom skirts

Cyclone locations

Town	Type	Amount	Status
Hereford, TX	125	7	Active
Bunceton, MO	120	1	Removed, Replaced by 2T22
Carrollton, MO	120	1	Active
Cheyenne, WY	120	4	Removed, some units were 50HP Powered. Replaced by 2001's
Toluca, IL	120	1	Active, has "hourglass" intake but no signs of a coding mechanism
New Richland, MN	120	1	Removed, Replaced by Eclipse-8 after it was struck by lightning, sold on auction
Eldon, MO	120	1	Inactive
Riyadh, Saudi Arabia	120	1	Removed, Ran in Pulse and Attack during attacks
Nekoosa, WI	125	1	Inactive, Motor died out
Philadelphia, PA	125	1	Active, Philadelphia Gas Works siren
Harrisburg, PA	125	60	Removed. Three Mile Island Nuclear, two units remain inactive.
Gore, OK	125	1	Inactive. Ex-Sequoyah Fuels
Newkirk, OK	125	1	Active. Reverse wired
Boynton, OK	125	1	Active
Bensenville, IL	125	3	Active
Contra Costa County, CA	125	9	Active, most used for Chevron Richmond Refinery
Orangeburg, SC	125	3	Active. SI Group sirens
Williams Bay, WI	125	1	Inactive
Park Falls, WI	125	2	Active
Howards Grove, WI	125	1	Active
Kiel, WI	125	2	Active, one was replaced by ASC AT-121
Campbellsport, WI	125	1	Active
La Farge, WI	125	1	Active
Somerset, WI	125	1	Active, optional 3-signal coding damper equipped
Waupun, WI	125	3	Removed, replaced by Federal Signal 508-128's
Cedarburg, WI	125	5	Removed, replaced by T-121's
Columbus, NE	125	3	Removed
Two Rivers, NE	125	1	Removed, replaced by T-128. Kewaunee Nuclear Power Plant
Two Creeks, WI	125	1	Removed, originally replaced an ACA Hurricane, was replaced by T-128. Kewaunee Nuclear Power Plant
Mequon, WI	125	6	Removed, replaced by T-135's
Amarillo, TX	125	8	Removed, some replaced by FS 508-128's
Canyon, TX	125	1	Inactive
Oyster Creek Nuclear Generating Station, NJ	125	31	Removed, most replaced with T-128s, only 2 remain
Seaside Park, NJ	125	1	Active as Fire Siren, Ex-Oyster Creek N.G.S.
Beach Haven, NJ	125	1	Inactive, former Coast Guard siren
Quinton, NJ	125	1	Removed, replaced by T-121, Was a part of Hope Creek Nuclear Power Plant and was Skirted
Salem, NJ	125	1	Removed, replaced by T-121, Was a part of Hope Creek Nuclear Power Plant and was Skirted
Alpha, NJ	125	1	Removed, placed near Rt. 80 and was a warning siren for Merrill Creek Reservoir
Maine Yankee Nuclear Power Plant, MA	125's	Unknown	Removed, were mentioned in an A.C.A. Demonstration Tape
Clydach, Wales U.K.	125	1	Removed, only cyclone in the entire European continent, possibly scrapped