Lockheed Martin SR-72 have the same range, with entry into service by 2030. The SR-72 follows the US Air Force's hypersonic road map for developing a hypersonic strike weapon by 2020, and a penetrating ISR aircraft by 2030. At the time of the concept's unveiling, Lockheed Martin had engaged in talks with government officials, but has not secured funding for the demonstrator or engine. On 13 November 2013, Air Force Chief of Staff General Mark Welsh revealed that the service was interested in the SR-72's hypersonic capabilities, but had not spoken with Lockheed Martin about the aircraft. Its high speed appeals to the
Martin/General Dynamics RB-57F Canberra the distinction of being the aircraft held the longest time (41 years) in extended storage before being returned to flight status. Martin/General Dynamics RB-57F Canberra The Martin/General Dynamics RB-57F Canberra is a specialized strategic reconnaissance aircraft developed in the 1960s for the United States Air Force by General Dynamics from the Martin B-57 Canberra tactical bomber, which itself was a license-built version of the English Electric Canberra. It was operationally assigned to the Air Weather Service for weather reconnaissance involving high-altitude atmospheric sampling and radiation detection in support of nuclear test monitoring, but four of the 21 modified aircraft performed