Read time: 8 min.

Nearly every community in Indiana has a series of sirens that alert people to inclement weather. In Delaware County, they’re tested every Friday at noon! Those hidden sentinels interrupted the tranquil rhythm of my week with a mix of unease and fascination when I was a kid, and I wanted to know more about them. Years later, I almost included some in the gigantic LEGO Muncie I designed during the COVID lockdown.

I started LEGO Muncie knowing I wanted to capture some obscure details to flesh out the models, and that’s where the sirens come in. My first attempt included three Federal Signal models found around Delaware County. From left to right, I designed a Thunderbolt-1000, an SD-10, and an SRN-2001 in scale with the skyline. Unfortunately, I had to paint with a broad brush, and the tiny size meant I had to give up key details that hurt their likeness. I deleted my working file and started over.

My second draft significantly increased the size of the sirens for more detail. I was pleased with how they turned out until I realized they were too big for LEGO Muncie! I may have eventually stumbled across a Mama Bear approach to get it just right, but I removed the sirens after I remembered that none of the buildings I’d chosen to depict actually featured one.

Aside from the weekly disruption, we don’t pay much attention to our outdoor warning sirens until the skies darken. Electromechanical models, like most Indiana counties use, were invented around the turn of the twentieth century. One of the earliest still in use was Federal Signal’s Model 2.

Both in LEGO and in real life, the sirens sort of look like upside-down pinecones. Federal Signal got its start in 1901 and the Model 2 debuted in 1929¹. The contraption was named after the amount of power it provided; Model 2s feature a two horsepower motor that drove a single-tone, 5-port chopper that can reach intensities of 102 dB from a hundred feet away². 

Over the years, Federal Signal developed more powerful versions of the Model 2, like the Model 5 and Model 7. They all look similar, and so do many distributed by the W.S. Darley Company! in the 1940s, Darley stopped making their Champion series of sirens and began distributing rebranded Federal Signal sirens³. My LEGO design tried to bridge the gap between the two cosmetic variations.

Originally, sirens like the Model 2 were used as fire alarms in small towns. Eventually, many were hooked up to countywide emergency management systems. I don’t have a good photo or video of them, but a pair of Model 2’s still grace the fire station in Daleville. Model 5’s can be found in Yorktown and Eaton, and Selma’s even home to Darley’s version! In fact, Federal Signal still sells the Model 2 nearly a century after it debuted. You can buy one for $3,800, and I almost have.

Federal Signal’s Thunderbolt-1000 was the next siren I recreated in LEGO. Designed from 1949 to 1952 to alert communities to impending Soviet attacks, it’s the one that looks like a trumpet. In 1958, six of them arrived in Muncie on the order of Marshall Sipe, Delaware County’s Director of Civil Defense⁴. The initial batch was installed at Riley and Roosevelt Elementary Schools, Franklin Middle School, Covalt’s Dairy, Broderick Company, and Ball Stores⁵.

Thunderbolts are unique among electromechanical sirens because they’re supercharged! Once one got word to start screaming via a phone signal from Muncie’s police radio station, it wailed at intensities as great as 127 dB from a hundred feet away. Hearing one is terrifying. These days, three Thunderbolt variations still call Muncie home.

One is in its original location at the old Riley School, but two were moved to South View Elementary and Meridian Health Service’s Suzanne Gresham Center. A fourth was at North View Elementary as recently as 2013. I got to hear the one at Meridian up close twice when I worked in a call center there for a few weeks, and now I hear it every Friday I’m at home. When I went to take video, the blast nearly made me drop my phone!

I’m enough of a weirdo to have a list of favorite warning sirens, and the Thunderbolt series tops it. That said, second place belongs to the ACA Banshee. The Thunderbolt atop Ball Stores was removed to make room for a new HVAC system in 1973⁶, and a Banshee 110 replaced it on top of the Delaware County Courthouse. The third siren I depicted in LEGO is a Banshee 115, the one that looks like a yellow pilgrim’s hat.

In 1968, a metal fabricator based in Milwaukee spun off its siren division to better compete with Federal Signal. Known as Alerting Communicators of America, the new company introduced its Banshee siren the same year to compete with sirens like Federal Signal’s STH-10 and SD-10, which I depicted in my first LEGO draft. Banshee 110’s featured a single-directional rotor and stator with a top-mounted motor.

Muncie’s Banshee is no longer yellow and doesn’t feature a motor cover, which makes it particularly susceptible to the weather it warned of. Today, Banshees are rare. According to the Indiana Siren Map administered by Spencer Harman, only six exist in Indiana, and four are in Kendallville! I’ve only heard Muncie’s Banshee once, but it was mean. Anyone who has ever been at the county building on a Friday can attest to how menacing they are.

The final siren I depicted is the Federal Signal SRN-2001. Variants of the design make up about sixty percent of Delaware County’s portfolio⁷. They’re ubiquitous! The model was introduced in 1988 as a replacement for the aging Thunderbolt. It can produce 126 dB from a hundred feet away!

The 2001-SRNB model replaced the 2001-SRN in 2002. Some early 2001-SRN models featured an arced rear housing. That’s the design I chose to model in LEGO, even though it’s not regionally accurate.

I live right by a traditional SRN-2001, but at least four of Delaware County’s outdoor warning sirens are 2001-SRNB’s. The village of Desoto is home to a 2001-130, a newer, more intense variation still sold by Federal Signal today⁷.

Aside from some variants, I skipped over a few sirens that still lurk around Delaware County as I designed them in LEGO. One is Gaston’s STH-10, a single-tone, ten-horsepower model produced for fifty years that stands behind town hall. Albany’s Darley variation was another.

All told, Delaware County is home to a mishmash of around forty outdoor warning sirens. A while back, I recorded the ones I could hear from my house with an SM-58 strung out to my balcony! I’m grateful for Fridays at home, since they provide different colors of sound based to where the sirens are pointed. I may be the only person who looks forward to the weekly test.

Even without an emergency, our hidden outdoor warning sirens remind me that our lives are sometimes a battle between the known and the mysterious; the seen and the unseen. Aside from the weekly test, the occasional call of Muncie’s old Thunderbolts, Daleville’s Model 2, or the pervasive SRN-2001s, serve as a haunting reminder that we should be vigilant!

Mass phone notifications may have taken over in 2023, but I’ll take the creepy wail of an electromechanical siren any day. They didn’t make my final design for LEGO Muncie, but it was still a lot of fun to reimagine Delaware County’s warning sirens in interlocking plastic blocks.

Sources Cited
1 Service Manual, Outdoor Warning Sirens Models 2 5 SD10 STH10 STL10 (n.d.). Signal Division, Federal Signal Corporation [Oak Brook]. Web. Retrieved March 25, 2023.
2 Trade Catalog (n.d.). W.S Darley & Co. The National Museum of American History Behring Center [Washington]. Web. Retrieved October 8, 2023.
3 Downtown Siren Last in CD Link (1958, March 17). The Muncie Evening Press. p. 1.
2 New CD sirens Will Be Tested Monday Morning (1958, March 21). The Muncie Star. p. 6.
4 Sirens’ Wails Are Check on CD Warning (1958, March 24). The Muncie Evening Press. p. 1.
5 Collier, W. (1974, June 7). Civil defense siren sounds in city again. The Muncie Evening Press. p. 1.
6 2001-130 Electro-Mechanical Siren (2007). Federal Signal Corporation [Oak Brook]. Web. Retrieved October 8, 2023.