The Harrier, the World s first vertical take off fighter evolved from the P.1127 project and the follow on from this, the Kestrel. The Harrier gradually evolved through the GR1-GR3 and the AV-8A, the American version. Later Aircraft were upgraded to the GR5, GR7 and the Mk GR9. Other Mks of Harrier were also operated by the Indian Navy and in Spain. The Harrier had a long and successful detachment of several years operating in Afghanistan, and was unrivalled throughout the World and playing a major part both on land and sea.