Cessna T-37 Tweet

https://en.wikipedia.org/wiki/Cessna_T-37_Tweet

The Cessna T-37 Tweet (designated Model 318 by Cessna) is a small, economical
twin-engined jet trainer type 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-37C was additionally capable of some light attack duties if
required. The A-37 Dragonfly variant served in the light attack role during the
Vietnam War and continues to serve in the air forces of several South American
nations.

The T-37 served as the U.S. Air Force's primary pilot training vehicle for over
52 years after its first flight. After completing Primary in the Tweet, students
moved on to other advanced Air Force, Navy, Marine Corps or Allied trainers.
With a total of 1,269 Cessna T-37s built, the USAF retired its last T-37 in
2009.

Origins

The Cessna Aircraft Company of Wichita, Kansas, provided the United States Army
during World War II and the Korean War with utility, light transport, and
observation aircraft, particularly the "O-1 Bird Dog" series.

In the spring of 1952, the USAF issued a request for proposals for a "Trainer
Experimental (TX)" program, specifying a lightweight, two-seat basic trainer for
introducing USAF cadets to jet aircraft.

Cessna responded to the TX request with a twin-jet design with side-by-side
seating. The USAF liked the Cessna design, which was given the company
designation "Model 318", and the side-by-side seating since it let the student
and instructor interact more closely than with tandem seating. In the spring of
1954, the USAF awarded Cessna a contract for three prototypes of the Model 318,
and a contract for a single static test aircraft. The Air Force designated the
type as XT-37.

The XT-37 had a low, straight wing, with the engines buried in the wing roots, a
clamshell-type canopy hinged to open vertically to the rear, a control layout
similar to that of contemporary operational USAF aircraft, ejection seats, and
tricycle landing gear with a wide track of 14 ft (4.3 m). It first flew on 12
October 1954.

The wide track and a steerable nosewheel made the aircraft easy to handle on the
ground, and the short landing gear avoided the need for access ladders and
service stands. The aircraft was designed to be simple to maintain, with more
than 100 access panels and doors. An experienced ground crew could change an
engine in about half an hour.

The XT-37 was aerodynamically clean, so much so that a speedbrake was fitted
behind the nosewheel doors to help increase drag for landing and for use in
other phases of flight. Since the short landing gear placed the engine air
intakes close to the ground, screens pivoted over the intakes from underneath
when the landing gear was extended, to prevent foreign object damage.

The XT-37 was fitted with two Continental-Teledyne J69-T-9 turbojet engines,
French Turbomeca Marboré engines built under license, with 920 lbf (4.1 kN)
thrust each. The engines had thrust attenuators to allow them to remain
spooled-up (i.e. rotating at speeds above idle) during landing approach,
permitting shorter landings while still allowing the aircraft to easily make
another go-around in case something went wrong. Empty weight of the XT-37 was
5,000 lb (2,300 kg).

Tests showed the XT-37 had a maximum speed of 390 mph (630 km/h) at altitude,
with a range of 935 mi (1,505 km). The aircraft had a service ceiling of 35,000
feet (10,700 m) but was unpressurized so was limited to an operational ceiling
of 25,000 feet (7,600 m) by USAF regulations.

The initial prototype crashed during spin tests. Later prototypes had new
features to improve handling, including long strakes along the nose, and an
extensively redesigned and enlarged tail. After these modifications, the USAF
found the aircraft acceptable to their needs, and ordered it into production as
the T-37A. Production aircraft remained tricky in recovering from a spin; the
recovery procedure was complex compared with most aircraft.

The Air Force ordered 444 T-37As, with the last produced in 1959. In 1957, the
US Army evaluated three T-37As for battlefield observation and other combat
support roles, but eventually procured the Grumman OV-1 Mohawk, instead.

The Air Force liked the T-37A, but considered it to be underpowered;
consequently, they ordered an improved version, the T-37B, with uprated
J-69-T-25 engines. The new engines provided about 10% more thrust and were more
reliable. Improved avionics were also specified for the new variant.

A total of 552 newly built T-37Bs was constructed through 1973. All surviving
T-37As were eventually upgraded to the T-37B standard, as well.

Due to a series of accidents caused by bird strikes between 1965 and 1970, all
T-37s were later retrofitted with a new windshield made of Lexan polycarbonate
plastic 0.5 in (12.7 mm) thick, which could tolerate the impact of a 4 lb (1.8
kg) bird at a relative speed of 288 mph (463 km/h).

In 1962, Cessna suggested the T-37B as a replacement for the North American
F-100 Super Sabre as the primary aircraft for the USAF aerobatic demonstration
team, the Thunderbirds, but the USAF was satisfied with the F-100.


Role
Military trainer aircraft

National origin
United States

Manufacturer
Cessna

First flight
12 October 1954

Introduction
1957

Retired
2009 (USAF)

Status
In service

Primary users
United States Air Force (historical)
Royal Moroccan Air Force
Turkish Air Force
Colombian Air Force

Produced
1955–1975

Number built
1,269

Variants
Cessna A-37 Dragonfly

Operational history

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. It was capable of all traditional aerobatic maneuvers. Students
intentionally placed the aircraft into a spin as part of their pilot training.

The Air Force made several attempts to replace the T-37 (including the Fairchild
T-46), but it remained in service with the USAF until it was phased out in favor
of the Beechcraft T-6 Texan II between 2001 and 2009. The T-6 is a turboprop
aircraft with more power, better fuel efficiency, and more modern avionics than
the Tweet.

The final USAF student training sortie by a T-37B aircraft in the Air Education
and Training Command took place on 17 June 2009. The last USAF operator of the
T-37B, the 80th Flying Training Wing, flew the sortie from its home station at
Sheppard AFB, Texas. The last T-37B was officially retired from active USAF
service on 31 July 2009.

Specifications (T-37B)

General characteristics
Crew: 2
Length: 29 ft 3 in (8.92 m)
Wingspan: 33 ft 99.3 in (12.581 m)
Height: 9 ft 2 in (2.79 m)
Wing area: 201 sq ft (18.7 m2)
Aspect ratio: 6.2:1
Airfoil: NACA 2418 at root, NACA 2412 at tip
Empty weight: 4,056 lb (1,840 kg)
Max takeoff weight: 6,574 lb (2,982 kg)
Powerplant: 2 × Continental-Teledyne J69-T-25 turbojets, 1,025 lbf (4.56 kN)
thrust each

Performance
Maximum speed: 425 mph (684 km/h, 369 kn)
Cruise speed: 360 mph (580 km/h, 310 kn) at 35,000 ft (11,000 m)
Stall speed: 85 mph (137 km/h, 74 kn)
Range: 932 mi (1,500 km, 810 nmi)
Service ceiling: 38,700 ft (11,800 m)
Rate of climb: 3,370 ft/min (17.1 m/s)

Armament

Total stores stations: None (T-37A/B), 2 underwing for stores up to 500 lb (227
kg) (T-37C)




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In one of his cartoons, Bob Stevens referred to the T37 as
"the converter"----- it converted JP-4 to noise

Dave:

In article , Old Geezerr says...

-*


In one of his cartoons, Bob Stevens referred to the T37 as
"the converter"----- it converted JP-4 to noise

Dave:



I'm surprised at how old it was...1954 on it's first flight.


*

Miloch wrote in
:

In article , Old Geezerr
says...

-*


In one of his cartoons, Bob Stevens referred to the T37 as
"the converter"----- it converted JP-4 to noise

Dave:



I'm surprised at how old it was...1954 on it's first flight.


*



My favorite Tweet image:

In article , Mitchell Holman
says...

Miloch wrote in
:

In article , Old Geezerr
says...

-*


In one of his cartoons, Bob Stevens referred to the T37 as
"the converter"----- it converted JP-4 to noise

Dave:



I'm surprised at how old it was...1954 on it's first flight.


*



My favorite Tweet image:


Since it was military, it stands to reason that they'd ALL be 'standing at
attention'...I don't see a slacker among them.



*

Old Geezerr wrote in
:

-*


In one of his cartoons, Bob Stevens referred to the T37 as
"the converter"----- it converted JP-4 to noise

Dave:



Side by side training is more effective
than the tandam seating, IMHO.