Boeing P-8 Poseidon

It is a generational leap. The P-3C Orion uses 4× T56 turboprops, reaches ~620 mph maximum speed and a 28,300 ft service ceiling, carries 13-15 crew, ranges to ~5,800 nmi, and runs 1960s-derived mission systems. The P-8 uses 2× CFM56 turbofans, tops out at 565 mph, climbs to 41,000 ft, carries 9 crew, ranges to 4,500 nmi, and runs a current-generation mission suite. The biggest practical change is the higher service ceiling — 41,000 ft versus 28,300 ft — which enables sonobuoy launch from cruise altitude rather than the P-3C's typical 200-500 ft profile. High-altitude operation cuts fuel burn sharply and extends mission endurance compared with the P-3C's low-altitude work.

Up to 129 internally, alongside other mission-equipment loads. The P-8 has 96 sonobuoy launch tubes — against the P-3C's typical 84 — with extra sonobuoys stowed for reload during long sorties. Types carried include passive LOFAR (Low-Frequency Analysis and Recording) for distant detection, active DICASS (Directional Command-Activated Sonobuoy System) for tracking, and specialised buoys. This is the highest sonobuoy capacity of any Western maritime-patrol aircraft, and it allows sustained tracking of multiple submarine targets simultaneously.

Yes. The P-8 carries up to 5 Mk-54 lightweight torpedoes internally for ASW prosecution. The Mk-54 is 9.5 ft long, 12.75 inches in diameter, with a 60 lb HBX warhead, ~12 nmi range, and ~40 knot speed at depth. It is gravity-released from the internal weapons bay and uses sonobuoy-derived target-position data plus its own seeker for terminal guidance. Compatible weapons also include the HAAWC (High-Altitude Anti-Submarine Warfare Weapon) glide-kit conversion of the Mk-54, enabling launch from 40,000+ ft rather than the traditional sub-1,000 ft profile. HAAWC has been in frontline service on the P-8 since around 2017.

Currently the AGM-84 Harpoon, with up to 2 mounted on underwing pylons. The Harpoon is a 1970s-vintage anti-ship missile with ~70 nmi range and a 488 lb warhead, still effective against unhardened surface targets. Future weapons under development or consideration include the AGM-158C LRASM (Long-Range Anti-Ship Missile, ~250 nmi range, integrated from 2021), the Naval Strike Missile (under integration, ~100 nmi range, low-observable), and future hypersonic anti-ship weapons. The P-8's anti-shipping reach is currently limited compared with dedicated maritime-strike platforms such as the F-15E or F/A-18E/F with LRASM, but planned upgrades will broaden it.

Yes, extensively, though specific detections are typically classified. Public examples include U.S. P-8 tracking of Russian Severodvinsk-class submarines in the North Atlantic in 2018, 2019, and 2022; combined U.S. and U.K. P-8 work against Russian Yasen-M class submarines from 2020 to 2023; Indian P-8I detection of Chinese submarines in the Indian Ocean in 2017 and from 2020 to 2023; and Australian P-8A detection of Chinese submarine activity in the South Pacific in 2019 and 2022. The improved sensor suite over the P-3C — particularly the high-altitude sonobuoy concept — has sharpened Western detection of contemporary Russian and Chinese boats.

Roughly $200-260M USD per airframe, depending on configuration and customer. U.S. Navy unit cost runs around $200M USD per P-8A, while allied and export customers pay $220-260M USD. Total programme costs — including support equipment, training, weapons, and infrastructure — reach $300-450M USD per airframe. The Indian P-8I programme (~12 aircraft, ~$3.5B USD total) and the Australian P-8A programme (~14 aircraft, ~$4.0B USD total) illustrate typical export pricing. The P-8 is far more expensive per airframe than the P-3C Orion it replaced, but offers a wider mission set and lower per-flight-hour operating costs.