Question about Trident D5

Hi guys, just was wondering if anyone could clear something up for me. There seems to be a conflicting stats for the Trident D5 missiles on the RN website. I'm possibly just interpreting things wrong but if someone could clear this up it would be appreciated.
On one page, it says the range is over 7000 miles and each missile can deliver 8 warheads, whereas on another page the range is over 4000 nautical miles and each missile can deliver 12 warheads? Just kind of want to know these details so I know what I'm talking about in my interview, thanks in advance!


War Hero
Doesn't take long really......

  • Unit cost: US$ 37.3 million
  • Range: With full load 4,230 nautical miles (7,840 km);
    with reduced load approx. 7,456 mi (12,000 km) (exact is classified)[8]
  • Maximum speed: Approximately 18,030 mph (29,020 km/h) (Mach 24)[1](terminal phase)
  • Guidance system: The MK 6 Astro-inertial guidance navigation system which is able to receive GPS (Global Positioning System) updates.
  • CEP: Requirement: 90 metres (300 ft). (Information from flight tests is classified.)
  • Warhead (in US usage only): The Mark 5 MIRV can carry up to 14 W88 (475 kt) warheads, while the Mark 4 MIRV can also carry 14 W76 (100 kt) warheads.[27][28] START I reduced this to eight. New START provides for further reductions in deployed launch vehicles, limiting the number of Submarine-launched ballistic missiles (SLBM) to 288, and the number of deployed SLBM warheads to a total of 1,152.
  • Warhead (in UK usage): Under a 1958 agreement, the U.S. supplies the UK with blueprints of its own warhead designs but the design, manufacture and maintenance of UK warheads are purely a UK responsibility. The Atomic Weapons Establishment (AWE) at Aldermaston constantly manufactures (and along with the maintenance and remanufacturing plant at Burghfield) a range of warheads of varying yield for fitting to Trident II missiles while pursuing ongoing research into new and improved warheads. Between 2005 and 2008 a £1.1bn program was undertaken to simulate and validate the safety and operation of the entire stockpile in to the mid 2020s without underground testing. The AWE has contributed scientists and £85m to the development of the Mk4A arming, fusing, and firing system at Sandia with the intention UK production at Aldermaston and fitting to existing warheads would commence in the latter half of the 2010s. The AWE is currently researching a fundamentally new warhead design to replace the existing design from the mid 2020s.[citation needed]
Good stuff.

The only discrepancy is in the missile guidance system. It does not use GPS (that is used for additional submarine positional accuracy) it uses stellar guidance for mid-flight course corrections.