{
  "id": "holbrook",
  "name": "Holbrook",
  "aliases": [],
  "domain": "nuclear",
  "country": "GBR",
  "category": "Nuclear warhead",
  "status": "active",
  "fielded": null,
  "operators": [
    "GBR"
  ],
  "summary": "UK Trident warhead, believed to be very similar to the U.S. W76-0; refurbished for the Mk4A aeroshell in 2023.",
  "specs": [
    {
      "k": "yield_kt",
      "v": 100,
      "src": [
        "fas-nn-gbr-2024"
      ],
      "conf": "medium",
      "note": "About 100 kt full yield"
    },
    {
      "k": "delivery",
      "v": "Trident II D5 (Mk4A)",
      "src": [
        "fas-nn-gbr-2024"
      ],
      "conf": "medium"
    }
  ],
  "payloads": [],
  "variants": [],
  "art": "nuclear",
  "image": null,
  "verified": null,
  "changelog": [
    {
      "date": "2026-11-08",
      "change": "Entry created from United Kingdom nuclear weapons, 2024 (FAS Nuclear Notebook)"
    }
  ],
  "url": "https://www.defensepedia.com/systems/holbrook.html",
  "sources": {
    "fas-nn-gbr-2024": {
      "title": "United Kingdom nuclear weapons, 2024",
      "publisher": "Federation of American Scientists Nuclear Notebook, Bulletin of the Atomic Scientists",
      "url": "https://fas.org/wp-content/uploads/2024/11/United-Kingdom-nuclear-weapons-2024.pdf",
      "published": "2024-11-12",
      "tier": 2,
      "checked": "2026-11-08"
    }
  }
}