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Then-Rear Admiral (lower half) Michelle J. Howard addresses the crew of USS Wasp (LHD-1).
General quarters
A call to general quarters aboard a United States Navy vessel
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1 Main Circuit (1MC) is the shipboard public address circuits on United States Navy and United States Coast Guard vessels. This provides a means of transmitting general information and orders to all internal ship spaces and topside areas, and is loud enough that all embarked personnel are (normally) able to hear it. It is used to put out general information to the ship's crew on a regular basis each day. The system consists of an amplifier-oscillator group which is located in the IC/gyro room, a microphone control station, portable microphones at each control station and loudspeakers located throughout the ship. Control stations for the 1MC announcing system are located at the pilot house, OOD stations on the quarterdecks, aft steering and Damage Control Central area.[1]

During an incident involving a casualty, the 1MC is a communication tool used by DCAs (damage control assistants) to keep ship members alerted and informed of casualty location area, status, and incident response efforts by the DC organization.

The 1MC is divided into smaller sub-circuits, such as officer's quarters and topside. At the option of the officer of the deck, some details are not passed on certain circuits.[1]

The 1MC is also used for transmitting various alarm sounds to alert the crew of specific impending dangers such as an inbound anti-ship missile, chemical attack, collision, or a flight deck crash.

Other circuits

[edit]
  • 2MC: Propulsion plant[2]
  • 3MC: Aviators[2]
  • 4MC: Damage control[2]
  • 5MC: Flight deck[2]
  • 6MC: Intership[2]
  • 7MC: Submarine control[2]
  • 8MC: Troop administration and control[2]
  • 9MC: Underwater troop communication[2]
  • 10MC: Well Deck
  • 18MC: Bridge[2]
  • 19MC: Aviation control
  • 21MC: Captain's command[2]
  • 22MC: Electronic control[2]
  • 23MC: Electrical control[2]
  • 24MC: Flag command[2]
  • 26MC: Machinery control[2]
  • 27MC: Sonar and radar control[2]
  • 29MC: Sonar control and information[2]
  • 30MC: Special weapons[2]
  • 31MC: Escape trunk[2]
  • 32MC: Weapons control[2]
  • 35MC: Launcher captains[2]
  • 39MC: Cargo handling[2]
  • 40MC: Flag administrative[2]
  • 42MC: CIC coordinating[2]
  • 44MC: Instrumentation space[2]
  • 45MC: Research operations[2]
  • 46MC: Aviation ordnance and missile handling[2]
  • 47MC: Torpedo control[2]
  • 50MC: Integrated operational intelligence center[2]
  • 51MC: Aircraft maintenance and handling control[2]
  • 53MC: Ship administrative[2]
  • 54MC: Repair officer's control[2]
  • 55MC: Sonar service[2]
  • 58MC: Hangar-deck damage control[2]
  • 59MC: SAMID alert[2]

Usage examples

[edit]
  • General Quarters: "General Quarters, General Quarters! All hands man your battle stations. The flow of traffic is up and forward on the starboard side, down and aft on the port side. Set material condition [place material condition here] throughout the ship. This is [or "is not"] a drill." "General Quarters, General Quarters!", "Up and forward", etc., refer to the flow of foot traffic as personnel make their way to their stations; the directions given are standard on U.S. Navy and U.S. Coast Guard vessels. The reason for General Quarters is generally given (such as "Fire in Main Space 2").
  • Sweepers: "Sweepers, Sweepers, man your brooms. Give the ship a clean sweep down both fore and aft! Sweep down all decks, ladders and passageways! Dump all garbage clear of the fantail! Sweepers." (Most ships today actually discourage throwing of trash over the side but instead use mulch/pulp rooms.) In port, "Dump all garbage clear of the fantail" is replaced with "Take all trash to the proper receptacles provided for on the pier."
  • 8 O'Clock Reports: "Lay before the mast all eight o'clock reports. Eight o'clock reports will be taken by the Executive Officer in the Executive Officer's stateroom." When in port Eight O'Clock Reports are normally taken by the Command Duty Officer at a location of the CDO's choosing.
  • Personnel Working Aloft: "There are personnel working aloft on board (ship), do not rotate, radiate, or energize any electric or electronic equipment, start gas turbines [or aboard submarines, "raise or lower any mast"], or operate ship's whistle while personnel are working aloft on board (ship)." Passed every thirty minutes and by all adjacent ships.
  • Divers Over the Side: "There are divers over the side, do not rotate screws, cycle rudders, operate sonar, take suction from or discharge to the sea, blow, flood, or vent any tanks, or operate any underwater equipment without first contacting the Chief Engineer and the diving supervisor." (Passed every thirty minutes)
  • Men in the Sail (RE: Submarine Tender craftsmen from the Repair Department R4 (Electrical/Electronic Repair) Division, ICs (Interior Communications Electricians)): "There are men working in the sail, do not raise or lower, rotate or radiate from any mast or antenna, there are men working in the sail." Passed every thirty minutes.
  • Reveille: "Reveille! Reveille! Reveille! All hands heave out and trice up. Reveille!" (Trice up is a reference to the past when enlisted personnel slept in hammocks. One end was detached at reveille and both ends attached to the same bulkhead, making the space available for other use. Also, in the past reveille would generally include 'the smoking lamp is lit in all berthing spaces'.
  • Tattoo: "Tattoo! Tattoo! Stand by for evening prayer. Silence about the decks." Given 5 minutes before Taps.
  • Taps: "Taps! Taps! Lights Out. All hands turn in to their racks and maintain silence about the decks. Taps."
  • Darken Ship: "Darken Ship! Make Darken Ship reports to DCS."
  • Fire: A rapid ringing of the bell on the quarterdeck and then one, two, or three single strokes of the bell are sounded (one for the forward third of the ship, two for middle third, and three for the after third). Then "Fire, Fire, Fire, Class (A, B, C, or D) Fire in Compartment [Compartment Number and Nomenclature if known]. Away the [at sea fire party (generally called "Flying Squad"), IET (In-port Emergency Team), or ship's fire fighting team] provide from Repair 2 (or closest Repair Station not inside the fire boundary)"
  • Breakaway music: Popular music played at the conclusion of an underway replenishment evolution. It is used to motivate the crew.
  • Submarine diving: "Dive, dive." (followed by two klaxon blasts then) "Dive, dive."
  • Security Alert: "Security Alert! Security Alert! Away the Security Alert team! Away the Back-up Alert force! All hands not involved in Security Alert stand fast! Reason for Security Alert: [state reason]"
  • Flight Quarters: "Flight Quarters! Flight Quarters! Set condition 1-alpha for flight operations! Set condition 1-alpha for hoisting and lowering of boats, port boat davit! The smoking lamp is out aft of frame 1-2-niner; all personnel not involved in flight operations stay forward of frame 1-2-niner! All personnel remove soft hats and refrain from throwing FOD material over the side!"
  • Testing shipwide alarm systems: "The following is a test of the ship's general, chemical, and collision alarms from the bridge --Disregard. [Test alarm sounds] Test complete, regard all further alarms!"
  • Testing flight deck crash alarm system: "The following is a test of the flight deck crash alert, conducted from the pilothouse, helo control tower, helo control bubble - disregard. [Test alarm sounds] Test sat, test complete. Regard all further alarms!"
  • Turn To; "Now Turn To" used to start the work day, usually at 08:00 and 13:00
  • Knock Off All Ship's Work; End of the working day.
  • Set Material Condition [condition]; Informs the crew on the correct default status for all watertight doors. Normal working hours would be X-ray, non-working hours would be Yoke and the tightest would be Zebra.
  • Liberty Call; Those with permission may leave the ship. "Now liberty call, liberty call. Liberty commences for the port (starboard) section. Liberty expires on board 0800 tomorrow (... Monday) morning. Now liberty call."
  • All announcements of an emergency nature are preceded with "Now this is (or is not) a drill".e.g. "Now this is a drill, this is a drill. Man overboard port side. All hands man your man overboard stations. This is a drill."
  • The arrival and departure of the commanding officer and dignitaries is announced. " Chief of Naval Operations, arriving (departing)." The CO is referred to by the ship's name.
[edit]
  • Crimson Tide, a 1995 submarine film, demonstrates in some detail the usage of the 1MC with regard to command instructions and ship-wide orders.
  • Battlestar Galactica (2003): The series shows frequent use of the 1MC general address system aboard Galactica, most often to warn of an incoming attack. The most typical format for this warning resembles, "Action Stations! Action Stations! Set Condition One throughout the ship! This is not a drill!"

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

1 Main Circuit

View on Grokipedia
from Grokipedia
The 1 Main Circuit (1MC) is the primary shipboard used on and vessels, enabling the transmission of general announcements, orders, and alerts to all compartments simultaneously. This one-way communication circuit serves as a critical tool for shipboard operations, disseminating routine information such as calls, evening prayers, and drill notifications, as well as urgent directives like or mass casualty alerts. It is integrated with the vessel's systems to ensure rapid dissemination of safety and operational messages across the entire ship. Transmitters for the 1MC are typically located at key stations, including the bridge, quarterdeck, and damage control central, with features allowing operators to isolate specific areas from non-essential broadcasts. Control of the system is restricted to authorized personnel, such as the , senior leaders like the Chief of Naval Operations during ship visits, or in emergencies, the damage control officer, with the ’s Mate of the Watch often responsible for making announcements. For example, on November 17, 2025, the Chief of Naval Operations delivered a 1MC address to the crew of USS Blue Ridge, stating, “You are at the center of our Navy’s mission in this region, and your work matters every single day.” of the 1MC falls under Interior Communications Electricians, who ensure its reliability amid the demands of over 30,000 pieces of communication equipment on modern warships. In the event of failure, temporary hardwired systems may be deployed to maintain announcing capabilities, underscoring its essential role in vessel readiness.

History

Origins and Development

Following , the U.S. Navy faced growing needs for effective public address systems on ships, as vessel sizes expanded and crew coordination became more complex amid larger complements and compartmentalized designs. In the 1920s, the Bureau of Construction and Repair oversaw the development of these systems, leading to initial installations on destroyers and battleships around the mid-decade. The Company, leveraging its expertise in moving-coil loudspeakers patented in 1913 and refined by 1917, constructed public address setups for naval vessels, enabling captains to communicate directly with the entire crew. Early prototypes encountered significant technical hurdles, including audio interference from engine noise and degradation due to saltwater corrosion in marine environments. Solutions incorporated anti-noise microphones, originally developed for Navy seaplanes during World War I, and in-house vacuum tube amplifiers to boost signal strength and clarity.

Adoption and Evolution

The 1 Main Circuit (1MC) saw adoption during World War II as a standard shipboard communication tool, becoming installed on U.S. Navy vessels including major warships such as the aircraft carrier USS Bunker Hill (CV-17). This implementation supported critical wartime operations, enabling efficient general announcements and alerts across the fleet amid intense Pacific Theater engagements. The U.S. integrated the 1MC during to enhance coordination during wartime convoy escort duties, adapting the system for use on smaller cutters and patrol vessels that operated alongside forces in . These adaptations ensured reliable intra-ship communication on platforms like the 165-foot cutters, which were repainted in Navy gray and armed for combat roles, reflecting the service's full operational alignment under command. Following the war, naval communication systems, including the 1MC, evolved from analog vacuum tube-based designs to transistorized systems in the 1960s, improving reliability and reducing size in line with broader naval electronics advancements. Digital enhancements to shipboard communication systems were introduced in subsequent decades, aligning with naval network modernizations. In line with Naval Sea Systems Command (NAVSEA) standards, the 1MC is required to remain operational during ship repairs, with temporary systems deployed if needed.

Technical Design

Core Components

The core components of the 1 Main Circuit (1MC) general announcing system consist of rugged, maritime-grade hardware engineered to withstand harsh shipboard conditions, including humidity, salt corrosion, and vibration. Microphone stations are located at key areas such as the bridge, quarterdeck, and damage control central, ensuring rapid access for command personnel during operations. Speaker arrays form the distribution network, comprising waterproof and corrosion-resistant reproducers mounted throughout the vessel to provide comprehensive audio coverage across all decks and compartments. These units are interconnected via cabling that resists from shipboard equipment. Control panels serve as the interface for system management, allowing for zone selection—such as excluding the captain's cabin—and basic adjustments. These panels enable precise to avoid disrupting sensitive areas. Power supply integration ensures operational reliability, with primary 115-volt AC feeds from the ship's electrical system and emergency backups to sustain functionality during power disruptions. The components collectively facilitate signal amplification and distribution, though detailed processing occurs in dedicated amplification stages.

Amplification and Distribution

The signal path for the 1MC begins at inputs located at control stations such as the bridge, , and damage control central, where audio is captured and initially processed through pre-s before reaching the central main banks. These banks, often modular transistorized units, deliver outputs in the range of 125 watts per channel to support ship-wide transmission, with total power capacities reaching up to 1000 watts when shared across circuits like the 1MC and 6MC. The amplified signal is then distributed via dedicated cabling networks to loudspeakers positioned throughout all ship spaces, ensuring comprehensive coverage above and below decks. To optimize voice clarity amid shipboard noise, the 1MC employs a focused on spectrum, typically incorporating bandpass filtering starting from 300 Hz to attenuate low-frequency interference while passing essential audio up to several kilohertz. This design reduces and enhances intelligibility for announcements, aligning with standards for audio circuits in the 300 to 10,000 Hz range. Zoned distribution enables selective of announcements, allowing switches at the control group to isolate specific areas—such as battle stations for urgent alerts or mess decks for routine messages—preventing unnecessary broadcasts to sensitive or irrelevant spaces like officer quarters. is incorporated through multiple parallel paths and integration with the ship's systems, providing capabilities to maintain operational integrity during faults or emergencies. Maintenance standards for the 1MC adhere to NAVSEA guidelines for shipboard communications equipment, including testing to verify , with maintained below 5% to ensure clear audio delivery. These procedures involve inspecting cabling, amplifiers, and relays for compliance with and safety protocols, such as those outlined in MIL-STD-1310 for grounding and shielding to prevent interference.

Operational Protocols

Standard Announcement Procedures

The 1 Main Circuit (1MC) serves as the primary means for routine, non-emergency announcements on U.S. Navy vessels, ensuring clear communication of daily schedules and administrative matters to the entire crew. These announcements typically begin with the preamble "Now hear this" or similar declarative phrasing to capture attention, followed by concise, scripted language that avoids slang or abbreviations for clarity. Daily routines form the core of standard 1MC usage, structuring the ship's operational rhythm. Reveille, sounded at approximately 0600, wakes the crew with the announcement: "Now reveille, reveille, all hands heave out and trice up. Give a clean sweep down fore and aft. The smoking lamp is lit in all authorized spaces." This call prompts sailors to rise, secure their bunks, and prepare for the day. Meal calls, such as for breakfast at 0630, lunch at 1130, and supper at 1730, are simply broadcast as "Mess call" to summon personnel to the galley without elaboration. Taps, typically at 2200, signals the end of the day with: "Taps, taps, lights out. All hands turn into your bunks. Maintain silence about the decks. The smoking lamp is out in all berthing compartments," enforcing rest and quiet. These scripted calls maintain uniformity across vessels, fostering discipline and efficiency. Administrative uses of the 1MC include personnel musters, such as the morning call at 0740: "Now all hands to for muster, , and instruction," which assembles the for accountability and briefings. Policy updates and welfare messages—covering topics like command directives or family notifications—are also transmitted routinely to keep the informed, often phrased declaratively for brevity, such as "All hands, lay before the mast for the 8 o’clock report." These announcements prioritize essential information to minimize disruption. Operator protocols require bridge authorization from the Officer of the Deck (OOD), Executive Officer (XO), or Captain before any transmission, with the Boatswain’s Mate of the Watch (BMOW) typically handling the announcement to ensure proper execution. For clarity, especially with names or critical details, the NATO phonetic alphabet is employed—e.g., "Alpha Bravo Charlie" for "ABC"—and key information is repeated at the end. This structured approach prevents misunderstandings in the noisy shipboard environment. Training for 1MC announcers emphasizes familiarity with circuits and protocols, integrated into broader shipboard communications drills as outlined in naval operations manuals. Personnel designated as operators, such as BMOWs, undergo periodic instruction to maintain proficiency, though specific frequencies vary by command. In contrast to these routine procedures, emergency overrides allow immediate use without for urgent situations. U.S. Coast Guard vessels employ similar 1MC protocols, aligned with Navy standards for announcements and authorizations, though adapted for cutter-specific operations as detailed in USCG specifications.

Emergency and Specialized Uses

The 1 Main Circuit (1MC) serves critical functions in emergency situations aboard U.S. Navy vessels by transmitting automated alarm tones that alert the crew to immediate threats, overriding manual microphone controls to ensure priority dissemination. These alarms are integrated with the ship's central alarm panels and include the general quarters signal for battle stations, which sounds a continuous bell followed by the announcement "General quarters, general quarters! All hands man your battle stations!" to mobilize personnel rapidly. Other key alarms encompass the collision warning, activated by the officer of the deck for imminent impacts, prompting the crew to brace and set material condition ZEBRA; the chemical attack alarm, triggered for chemical, biological, or radiological threats, directing donning of protective gear; the flight crash alarm for aviation incidents; and the man overboard signal, consisting of three prolonged blasts on the ship's whistle supplemented by a 1MC verbal call-out such as "Man overboard, starboard side," to initiate search and rescue procedures. In damage control scenarios, such as damage, fires, or accidents, the 1MC enables directed evacuations and real-time instructions from damage control central or the bridge, with priority override circuits ensuring alarms preempt verbal announcements to prevent confusion during crises. For instance, during a or flooding event, the damage control assistant may use the 1MC to issue commands like "Away the fire-fighting team" or specify evacuation routes, coordinating efforts across compartments while maintaining crew . This system's , with control stations in damage control central and after steering, supports sustained operations even if primary circuits fail, as demonstrated in evolutions that replicate wartime casualties. Specialized modes of the 1MC extend to chemical, biological, and radiological (CBR) alerts via the dedicated chemical attack alarm, which integrates with the ship's CBR defense systems to broadcast protective action directives, such as masking and procedures, ensuring rapid response to hazardous environments.

Other Main Circuits

In addition to the primary 1MC, U.S. vessels employ several secondary main circuits tailored to specific operational departments, enabling focused communication without the shipwide reach of the 1MC. These circuits maintain narrower scopes, covering fewer zones and incorporating department-specific access controls to ensure efficient, targeted information flow during routine and emergency situations. The 2MC, known as the Announcing Circuit, serves intra-engineering spaces for transmitting orders and information related to the propulsion plant, including machinery status updates and damage reports. Limited primarily to lower decks and engineering machinery areas, it operates as a one-way system to coordinate engineering teams without disrupting other ship sections. On aircraft carriers, the 3MC, or Aviation Announcing Circuit, supports and coordination by providing amplified voice announcements for aviators and troops, such as turn-up warnings and instructions during launches and recoveries. Typically confined to the and related spaces, it facilitates real-time safety directives, like "STAND WELL CLEAR OF HELO NUMBER __ WHILE ENGAGING/DISENGAGING ROTORS," and integrates with flight warning alarms for urgent alerts. The 4MC functions as the Damage Control Circuit, enabling two-way emergency reporting and announcing for rapid response to casualties, such as fires or flooding, using dedicated switchboxes like the SA-718/WIC. Restricted to damage control personnel and relevant zones, it prioritizes immediate coordination from the bridge to repair teams, differing from the 1MC by allowing bidirectional in crisis scenarios. The 5MC, designated the Announcing Circuit on carriers, delivers air traffic directives and alerts to crews, including commands for operations, deck status changes (e.g., "FOUL DECK, FOUL DECK, STRIP THE NUMBER ___ WIRE"), and crash response coordination. Equipped with features like mandated silence during critical phases to counter jet noise and hearing protection protocols, it is limited to topside areas for precise operational control.

Integration with Shipboard Communications

The 1 Main Circuit (1MC) interfaces with various shipboard communication networks to enable coordinated voice distribution across naval vessels. It connects to systems such as the 21MC, allowing for selective muting of entertainment audio during announcements and shared wiring configurations for maintenance efficiency. Additionally, the 1MC ties into external relay systems, including high-frequency (HF) and very high-frequency (VHF) radios via radio interface units that permit dial access for , as well as communications through digitized and encrypted channels reallocated to IP networks for enhanced bandwidth utilization. Centralized control of the 1MC occurs through the ship's communication center, often utilizing the Integrated Voice Communication System (IVCS), which manages priority queuing for multi-system alerts to ensure critical messages override routine transmissions. This setup allows up to six group combinations for targeted announcements while integrating with terminals for continuous monitoring of radio channels. Modern upgrades in vessels like the DDG-1000 Zumwalt-class destroyers incorporate IP-based integration, transitioning the 1MC to digital audio over Ethernet via Voice-over-IP (VoIP) protocols and interworking functions that consolidate analog signals into a unified network. This supports net-centric warfare by enabling modular terminals with removable encryption for secure, multi-level communications. Reliability protocols for the 1MC include failover mechanisms to backup systems during electromagnetic pulse (EMP) events or cyber threats, as outlined in Navy engineering guidelines for shipboard equipment hardening and cybersecurity directives emphasizing redundant processors, battery backups, and emergency throw-over modes to maintain at least one-hour operation. These features ensure continued functionality through built-in test equipment and dual power supplies, aligning with broader IVCS redundancies.

Cultural and Historical Significance

Depictions in Media

The 1 Main Circuit (1MC), as the primary shipboard in the U.S. Navy, has been portrayed in various media as a symbol of and urgency in naval settings, often amplifying dramatic tension during crises. These depictions frequently highlight the system's role in issuing alarms or captain's orders, underscoring the hierarchical structure aboard warships and submarines. While such representations capture the 1MC's essential function in coordinating crew responses, they sometimes prioritize cinematic effect over technical precision. In films, the 1MC features prominently in submarine thrillers to convey imminent threats. For instance, in The Hunt for Red October (1990), the announcement—"General quarters, general quarters, all hands man your battle stations"—is broadcast over the PA system on the USS Dallas. Similarly, Crimson Tide (1995) depicts the 1MC during a launch on the , where an initial "this is an exercise" message escalates to a real emergency following a kitchen fire, emphasizing the system's dual use for routine and critical alerts. In (2001), a dramatized attack sequence includes a 1MC call on the USS to rally the crew amid the 1941 Japanese assault. Literature often employs the 1MC to illustrate operational command in military fiction. Tom Clancy's The Hunt for Red October (1984) references the system in scenes aboard U.S. and Soviet submarines, where announcements reinforce the captain's voice as a tool of decisive leadership during defection and pursuit sequences, reflecting Clancy's research into naval protocols. Another Clancy work, Red Storm Rising (1986), uses the 1MC on the USS Pharris to signal the transition from drills to live combat, marking the crew's entry into a full-scale war. Television series set in naval environments routinely incorporate the 1MC for procedural authenticity. In The Last Ship (2014–2018), the system is explicitly named in episodes like Season 2, Episode 5, with lines such as "This is the last 1MC message for a while," used to communicate strategic updates to the crew of the USS Nathan James amid a global pandemic crisis. Procedural dramas like JAG (1995–2005) feature shipboard scenes with overhead announcements mimicking 1MC calls for routine briefings and emergency drills, highlighting its integration into daily Navy life. Media portrayals sometimes introduce inaccuracies for dramatic impact, such as artificial echoing or reverb in 1MC audio to heighten suspense, whereas real systems deliver clear, direct broadcasts without such effects to ensure clarity across ship compartments. These tropes, while engaging, can exaggerate the 1MC's sonic presence beyond its practical design.

Notable Events and Incidents

During , the Japanese surrender ceremony took place aboard the on September 2, 1945. Captain Stuart S. Murray hosted the historic event. In the Cold War era, the 1MC was essential for issuing urgent alerts on U.S. Navy vessels enforcing the naval quarantine of Cuba during the 1962 Cuban Missile Crisis. On the destroyer USS Abbot (DD-629), a false fire alarm in the starboard hedgehog magazine and a man-overboard alert heightened crew readiness during the tense standoff. In modern incidents, the 1MC facilitated emergency responses following the al-Qaeda bombing of the USS Cole (DDG-67) on October 12, 2000, in Aden, Yemen, which killed 17 sailors and injured 39. Although the initial explosion disabled much of the system's power, it was later used to announce "flooding, flooding, flooding" around midnight on October 13 when a seal failed in Main Engine Room 2, prompting immediate damage control efforts to prevent further casualties. The 1MC also proved vital for health updates during the COVID-19 pandemic on U.S. aircraft carriers in 2020. On the USS Ronald Reagan (CVN-76), standard announcements over the 1MC reported influenza-like illness (ILI) cases—coded for potential COVID-19—to initiate rapid isolation protocols, such as: "I-L-I reported in compartment three tack, one eight zero tack, zero tack, quebec. Away the COVID response team away. All hands not involved stand clear." This practice, implemented since November 2020, helped contain outbreaks by directing medical teams to escort symptomatic sailors to isolated treatment areas. Post-incident reviews of major naval accidents have influenced procedures. Following the April 19, 1989, turret explosion on the USS Iowa (BB-61), which killed 47 sailors due to an overrammed powder charge, the 's investigations highlighted deficiencies in training, supervision, and safety procedures, leading to reforms in these areas.

References

  1. https://media.defense.gov/2014/Feb/21/2002655432/-1/-1/1/140221-N-ZZ182-5351.pdf
  2. https://www.dcms.uscg.mil/Portals/10/CG-4/documents/SFLC/StandardSpec2018/SFLC-Std-Spec-8635-%282018%29.pdf
  3. https://www.navy.mil/Press-Office/News-Stories/display-news/Article/2259742/ics-keep-boxer-in-touch/
  4. https://www.instagram.com/p/DRHP6PAkbjm/
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  6. https://www.history.navy.mil/research/histories/ship-histories/danfs/b/bunker-hill-i.html
  7. https://www.history.navy.mil/browse-by-topic/wars-conflicts-and-operations/world-war-ii/1945/battle-of-okinawa/dangerous-okinawa.html
  8. https://warfarehistorynetwork.com/article/u-s-coast-world-war-ii/
  9. https://apps.dtic.mil/sti/tr/pdf/ADA084225.pdf
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  14. https://dynalec.com/products/announcing-and-intercom/61652-000
  15. https://www.dynalec.com/products/announcing-and-intercom/60403
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  18. http://www.usscollett.com/history/f_olderr/12-25-14/1MC%20Announcements%20for%20Evolutions.pdf
  19. https://media.defense.gov/2014/Feb/21/2002655450/-1/-1/1/140221-N-ZZ182-5359.pdf
  20. https://www.navy.mil/Press-Office/Press-Releases/display-pressreleases/Article/2253098/ike-sailors-prepare-to-save-ship-one-gq-at-a-time/
  21. https://www.navy.mil/Press-Office/News-Stories/Article/2240211/medical-emergency-the-importance-of-medical-drills/
  22. https://nj2bb.org/reference/Ship%27s_Comms_Circuits.pdf
  23. https://info.publicintelligence.net/USNavy-CVN-FlightDeck.pdf
  24. https://www.dvidshub.net/news/304419/cs-9-crucial-communications
  25. https://apps.dtic.mil/sti/tr/pdf/ADA072514.pdf
  26. https://apps.dtic.mil/sti/tr/pdf/ADA123711.pdf
  27. https://www.cool.osd.mil/usn/ia_documents/COMNAVCYBERFORINST-5239-2D.pdf
  28. https://www.imdb.com/title/tt0099810/
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  32. https://abbot.us/missileCrisis/
  33. https://www.history.navy.mil/content/dam/nhhc/research/publications/publication-508-pdf/Case%20Studies%20in%20Damage%20Control_508%20FINAL.pdf
  34. https://www.navy.mil/Press-Office/News-Stories/display-news/Article/2513106/an-unseen-adversary-uss-ronald-reagans-unprecedented-fight-against-covid-19/
  35. https://www.gao.gov/assets/nsiad-91-4.pdf
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