In response to the T-37A being underpowered, the USAF ordered an improved version, the T-37B, that was powered by uprated J-69-T-25 engines and was also equipped with improved avionics. A total of 552 new-built T-37Bs were constructed through 1973; all surviving T-37As were eventually upgraded to the T-37B standard as well.

The T-37 is a twin-engine primary trainer used for teaching the fundamentals of jet aircraft operation and for flying on instruments, in formation and at night. Affectionately known as the "Tweety Bird," it was the first U.S. Air Force jet designed from,

T-37鳴鳥式教練機 （英語： T-37 Tweet）是 美國 在 第二次世界大戰 後首種噴射教練機，1952年委託 西斯納飛機公司 研製，目的是要去取代各種 螺旋槳 教練機，T-37於1957年進入 美國空軍 服役.

The T-37B is an improved version outfitted with two J69-T-25 turbojet engines and enhanced navigation and communications equipment. The T-37C is a light-attack version with weapons pylons under each wing.

T-37B在T-37A的基础上改进了 无线电导航系统 、UHF无线电接收系统，并重新设计了一表面版。 T-37B被包括泰国、希腊、智利、约旦、土耳其和巴基斯坦等许多国家在内的空军所使用。 1959年投入使用。 所有的T-37A都被改造成了T-37B。 T-37C和T-37B相似，但配备了外挂武器和 翼尖 副油箱，可携带两枚250重的 炸弹，并可携带照相机完成侦察任务。 使用T-37C的国家有葡萄牙、秘鲁、哥伦比亚和希腊等。 T-37共被生产了1000多架，其中507架至今仍在美国空军服役。 它 …

The T-37 is a twin-engine primary trainer used for teaching the fundamentals of jet aircraft operation and instrument, formation, and night flying. Affectionately known as the Tweety Bird, it was the first USAF jet aircraft designed from conception as a trainer (as opposed to a modification such as the T-33).

The T-37A was delivered to the U.S. Air Force beginning in June 1956. The USAF began cadet training in the T-37A during 1957. The first T-37B was delivered in 1959. Instructors and students considered the T-37A a pleasant aircraft to fly. It handled well and was agile and responsive, though it was definitely not overpowered.

The T-37 has a hydraulically operated speed brakes, tricycle landing gear and a steerable nose wheel. Six rubber-cell, interconnected fuel tanks in each wing feed the main tank in the fuselage. The T-37B has improved radio navigational equipment, UHF …

The Cessna T-37 Tweet (designated Model 318 by Cessna) is a small, economical Twin-engine jet trainer-attack type aircraft which flew for decades as a primary trainer for the United States Air Force (USAF) and in the air forces of several other nations.

The T-37B was a winning design that might have been improved by replacing the two J69-T-25 turbojets with one J85-GE-4 that pushed out 2950 lbf of thrust with a weight savings of over 400 lbs. A single engine redesign using either the J85 or its 4250 lbf thrust TF37 derivative would have been my choice over the Texan II.