Hawk followed, and common improvements to the base design typically included increased range, more powerful engines, redesigned wing and undercarriage, the addition of radar and forward-looking infrared, GPS navigation, and night-vision compatibility. Later models were manufactured with a great variety in terms of avionics fittings and system compatibility to suit the individual customer nation; cockpit functionality was often rearranged and programmed to be common to an operator's main fighter fleet to increase the Hawk's training value. In 1981, a derivative of the Hawk was selected by the United States Navy as their new trainer aircraft. Designated the McDonnell Douglas T-45 Goshawk, the design was adapted to naval service and strengthened to withstand operating directly from the decks of carriers, in addition to typical land-based duties. This T-45 entered service in 1994; initial aircraft had analogue cockpits, while later deliveries featured a digital glass cockpit. All airframes were planned to undergo avionics upgrades to a common standard. Further development A major competitor to the Hawk for export sales has been the Dassault/Dornier Alpha Jet; aviation expert John W. R. Taylor commented: "What Europe must avoid is the kind of wasteful competition that has the Hawker Siddeley Hawk and Dassault-Breguet/Dornier Alpha Jet battling against each other in the world market." By early 1998, a total of 734 Hawks had been sold, more than 550 of which had been sold to export customers. Military customers often procured the Hawk as a replacement for older aircraft such as the BAC Strikemaster, Hawker Hunter, and Douglas A-4 Skyhawk. During the 1980s and 1990s, British Aerospace, the successor company to Hawker Siddeley, was trying to gain export sales of the variable-wing Panavia Tornado strike aircraft; however, countries such as Thailand and Indonesia, which had shown initial interest in the Tornado, concluded that the Hawk is a more suitable and preferable aircraft for their requirements. Malaysia and Oman cancelled their arranged Tornado orders in the early 1990s, both choosing to procure the Hawk, instead. Aviation authors Norman Polmar and Dana Bell stated of the Hawk: "Of the many similar designs competing for a share of the world market, the Hawk has been without equal in performance as well as sales". On 22 December 2004, the Ministry of Defence awarded a contract to BAE Systems to develop an advanced model of the Hawk for the RAF and Royal Navy. The Hawk Mk. 128, otherwise designated as Hawk T2,