O'ahu has always been known for it's large system of Thunderbolts among the siren community. Many of us have seen & heard these 'bolts in action during the 2010 Chile earthquake, 2011 Japan earthquake & 2012 Canada earthquake tsunami warnings. Growing up less than 1000 feet away from a 1000BT in Kailua was one of the highlights of my younger days, & the nostalgia still lingers. For over 60 years, the Thunderbolt has been an icon of public safety on the Island of O'ahu, taking "the roar of the Thunderbolt is unmistakable" to a whole new level amongst us locals. As the decades went by, our harsh & salty climate has practically eaten through many of our legacy sirens, with excessive rust making maintenance borderline impossible. For a while, our state had to jump through hoops just to keep these old legacy units active. Sourcing spare parts from previously removed units, & in some cases completely re-winding motors & re-assembling "Frankenstein" sirens back together with all their hand-me-down spare parts as needed. In recent years, they completely abandoned the old VHF radio system & upgraded all their legacy sirens with satellite & cellular activation capabilities. For decades, they were surprisingly successful at breathing new life into these legacy sirens every time there was a failure. However in recent years, the hourglass for these relics has almost run out entirely. Between rotting & leaning poles, half century old wiring, excessive rust & intrusive wildlife, our era of legacy sirens, mechanical & electronic, is coming to a close.
Ladies & Gentlemen of the siren board, as of today (3/4/2023), the entire state of Hawai'i is down to just 1 active Thunderbolt. A lone 1000BT in the town of Kalihi is the only active remnant from the original cold war era Thunderbolt system. For us Hawai'i enthusiasts, this is a rather big deal considering how drastically the system has changed up in the past few years alone. If anybody is planning a trip to O'ahu & wishes to record a 'bolt, I recommend you do so soon. The Kalihi Thunderbolt is still quite healthy, but I'm almost certain it will not be repaired should any electrical or mechanical issues arise. Previously, the only other active 'bolt was located at Aiea Heights. Today, that Aiea Heights siren kicked the bucket & it's chopper failed to activate. I guarantee this siren won't be repaired, since the state is planning on replacing all legacy units at this point. Surprisingly, an RSH-10A still stands on O'ahu, connected to power & still tied into the sat/cell system. However this Thunderbeam is in pitiful condition, & it's reliability would be best described as flakey in the best scenario. It's already failed at least once this year, and has a massive rust hole atop the siren which has become a gateway for birds & debris. I wouldn't be surprised if it's failed again this month, for good.
Our states go-to siren, the Modulator 6024B, has proven to be a reliable choice. Sure, it's output is nothing compared to the units of the OG legacy system, but reliability is the priority. With more & more units being installed in gap areas to make up for lost coverage, the massive system of 400+ electronic sirens has definitely earned it's keep. Plus, standardizing the entire system to just one specific model definitely helps keep maintenance costs down, especially when money & funding is limited. The new MOD's have proven to withstand the harsh climate well, much better than the I-Forces that were installed around a decade ago. In fact, all remaining I-Forces, except for 1, have been replaced with 6024B's. Unfortunately, ASC's controllers were not compatible with the sat/cell activation. Furthermore, the top mounted solar panels were notorious for collapsing due to corrosion on the brackets used to suspend them above the siren's head. The surviving I-Force 1600 at Ala Wai Boat Harbor now uses FS UV controls, set to 850/1020hz dual tone like the rest of the system. O'ahu does have 3 remaining EOWS 612's, although 1 failed today's monthly test due to dead batteries caused by a very dirty solar panel. A lone 1212 also stands & remains active, but it's days are numbered. All EOWS sirens in Hawai'i have been upgraded with UV's. Currently, no SiraTone controllers remain in the system. Even the US Army Garrison Hawai'i, who operated a system of over a dozen SiraTone MOD3012's, has completely replaced their sirens with brand new 2nd generation "B' series Modulators. These new Modulators owned by the Army are tested monthly, in tandem alongside the state's system just like the JBPHH sirens. On neighboring islands, several dozen EOWS units remain active, once again all on UltraVoice. If all is still well, a lone RSH-10 on Maui & several late model STH-10's also remain active, however these will soon be replaced just like all other legacy sirens.
In conclusion, Hawai'i''s statewide siren system has definitely come a long way over the past decade. Regular upgrades have kept most communities within decent earshot of a siren, ensuring the system remains effective for everybody. Although it's sad to see the 'bolts go, it's certainly for the better. As international tensions grow, we need our sirens to be reliable, just in case. Despite the state no longer testing the attack tone monthly, they can & will be activated in attack for a legitimate war related emergency. In fact, the state is now calling the sirens "All Hazard outdoor warning sirens for public safety" emphasizing their role as multi-use sirens for all forms of emergencies. I think it's safe to say sirens will continue to play a significant public safety role in our state for decades to come. Below is a photo of the last active Thunderbolt in the entire state. I'll also add a link to my last recording of it back in November of 2022.
https://www.youtube.com/watch?v=QnEtC2pWstI