OVERVIEW: The Harrier T.4N belongs to the first generation of the Harrier family, subsonic, twin-seat V/STOL (Vertical and/or Short Take-Off and Landin), trainer aircraft used by the Royal Navy. It was developed from the T.4A and modified for naval pilot training and Sea Harrier conversion operations.

DETAILS: The T.4N entered service with the Royal Navy in 1979 as a dedicated trainer for Sea Harrier FRS.1 pilots. It was powered by the Rolls-Royce Pegasus Mk 104 turbofan engine, delivering approximately 21,500 lbf of thrust. The T.4N retained the lengthened two-seat fuselage and high tail of the T.4 series, but added features for shipboard use such as corrosion-resistant components, deck handling modifications, and strengthened undercarriage. It lacked the Blue Fox radar but retained an active radar warning receiver in the tail fairing, matching the Sea Harrier’s defensive profile. The aircraft had five underwing hardpoints and could carry practice weapons or training stores but was not used in combat.

The “T” stands for Trainer, while “N” indicates its naval configuration. Unlike the RAF’s T.4A, the T.4N added naval systems required for carrier operations, including landing aids, RWR, and modifications for maritime corrosion resistance, while omitting radar to reduce cost and weight.

TYPE: V/STOL trainer and conversion aircraft

FUNCTION: The T.4N was used for Sea Harrier pilot conversion and deck-landing qualification with squadrons such as 899 Naval Air Squadron. It enabled realistic training without using frontline combat aircraft, ensuring safe transition to naval Harrier operations.

NOTE:
IOC: 1979
IOC of related variants: T.4 – 1977 | T.4A – 1977 | GR.3 – 1973
Operators: United Kingdom
Manufacturer: British Aerospace (United Kingdom)
Conflict used in: None

SOURCE:
Royal Navy Harrier Training History: https://dunsfoldairfield.org/harrier-part-2-of-3/ ; British Aircraft Corporation Harrier Overview: https://www.bcar.org.uk/bae-harrier ; Wikipedia – List of Harrier Variants: https://en.wikipedia.org/wiki/List_of_Harrier_variants ; Harrier Training Airframes: https://www.hyperscale.com/2017/reviews/kits/sw72098reviewmd_1.htm