the support organization for continuing operators. Operational history Over 800 Sabreliners were produced, of which 200 were T-39s. A number of retired military T-39s have also entered the civilian world since the military versions also carry FAA type certification. , 56 examples have been lost in accidents. The Series 65 was the last series run and 76 of them were produced, mostly for the private market. Monsanto has the oldest continuously operating company corporate jet division starting with its purchase of a Sabreliner 40. T-39s were used in support of combat operations in Southeast Asia during the Vietnam War. In late 1965 T-39s replaced Martin B-57 Canberras on flights to transport high-priority cargo, such as exposed film from photoreconnaissance missions, from outlying bases to Saigon. The original Navy version, the T3J-1, redesignated T-39D after the 1962 redesignation of USN/USMC/USCG aircraft, was initially fitted with the radar system from the McDonnell F3H-1 Demon all-weather fighter and used as a radar trainer for pilots of that aircraft. The T-39D aircraft was subsequently introduced into the Basic Naval Aviation Observer (NAO), later Student Naval Flight Officer (SNFO) program. Three versions of the T-39D were used throughout the 1960s, '70s, and '80s: one without radar for high altitude instrument navigation training and low altitude visual navigation training in the SNFO Intermediate syllabus; a second variant equipped with the APQ-126 radar from the LTV A-7 Corsair II for training primarily bombardier/navigators, reconnaissance attack navigators, and electronic countermeasures officers in attack aircraft; and a third variant with the APQ-94 radar for training pilots of the Vought F-8 Crusader. The T-39N and T-39G are currently used in the NFO Strike and Strike Fighter syllabi in training USN and USMC student Naval Flight Officers, as well as various NATO/allied/coalition student navigators. Foreign students also train in the T-39 in place of the Beechcraft T-1 Jayhawk during the Intermediate Jet syllabus. The Sabreliner requires a minimum crew of two and, depending on cabin configuration, can carry up to seven passengers (NA-265 through NA-265-40) or ten passengers (NA-265-60 and subsequent models). As a Navy flight training aircraft, it will typically fly with a pilot, one or two NFO instructors, and two to three student NFOs or student navigators/CSOs. Being derived from the F-86, the Sabreliner is the only business jet authorised for aerobatics and is used by two California companies: Flight Research Inc. and Patriots Jet Team, for inflight upset-recovery