Military


T-34 Mentor / T-34C Turbo Mentor

The T-34 Mentor began as a private venture designed by Walter Beech shortly after WW II. Beech felt that there was a market for a military trainer based on the Model 35 Bonanza which had been flying for about a year.

Beech used the Bonanza as a starting point and began work on the design of the Model 45. The first two prototypes were powered by 205 hp Continental engines while the third had a more powerful 225 horsepower engine. The prototype made its first flight Dec. 2, 1948. The aircraft were then shown to the Air Force which ordered three military test aircraft under the designation YT-34. It wasn't until late 1952 the Air Force ordered the YT-34 into production under the designation T-34.

The T-34 spent a quarter of a century in use as a pilot trainer. The first of 350 aircraft were delivered to the Air Force in 1953 with the Navy receiving its first of 423 aircraft in 1954.

The T-34 design was rugged and reliable and best of all it was all metal construction. Many trainers as late as WW II were not. The T-34 also had many parts in common with different models of the Beech Bonanza and Debonair. Replacement parts were readily available and kept costs down.

Both the Air Force and the Navy found it to be an excellent aircraft. Particularly for the intermediate phase of training before going to jet aircraft.

In 1973, some T-34s received turboprop engines with about twice the power of the piston engine. This model, the T-34B, was used both as a trainer and light attack aircraft. The U.S. Navy and some Latin American countries are still using the turboprop version today.

T-34C Turbo Mentor

The T-34C aircraft is an unpressurized two-place, tandem cockpit low-wing single-engine monoplane manufactured by Raytheon Aircraft Company (Formally Beech Aircraft), Wichita, Kansas. The aircraft is powered by a Model PT6A-25 turbo-prop engine manufactured by Pratt & Whitney Aircraft of Canada. The primary mission of the T-34C is to provide primary flight training for student pilots attached to the Chief of Naval Air Training. As a secondary mission, approximately 10% of the aircraft provide pilot proficiency and other aircraft support services to AIRLANT, AIRPAC, and NAVAIR "satellite sites" operated throughout CONUS.

Students selected to attend joint Specialized Undergraduate Pilot Training [SUPT] with the US Navy attend aviation preflight indoctrination (API) at NAS Pensacola, Fla., for six weeks learning basic preflight topics covered in Air Force's phase I program. Following API, pilot students attend the primary and intermediate phases of flight training at NAS Whiting Field, Fla. Joint primary training takes approximately 33 weeks and includes 159 hours of ground training, 37 hours in the flight simulator, and 92 flying hours in the T-34.

The T-34C aircraft was procured as a commercial-derivative aircraft certified under an FAA Type Certificate. Throughout its life, the aircraft has been operated and commercially supported by the Navy using FAA processes, procedures and certifications. It continues to be maintained commercially at all levels of maintenance, and relies on COTS/NDI components and equipment to support airworthiness. Aircraft modification efforts are "turnkey" projects (procurement and installation) implemented as part of competitively awarded maintenance contracts. Where extensive integration efforts are required, the non-recurring engineering phase, including test and certification, is typically performed by Raytheon Aircraft Company under a sole-source engineering contract with the Navy.

The plane is a tandem two seat, low wing Beech with a 235hp engine, retractable gear and a constant speed propeller. It differs from the other aircraft because it has a world War II style bubble canopy and a flight stick instead of a yoke. Cruise speed is around 135 knots, and cruise climb will produce a rate of about 500 feet per minute. This aircraft was built for maneuverability. With light stick forces this plane can roll, turn, and loop around any other at the field.

The bubble canopy gives great visibility in all direction, making for a very dramatic difference from the usual cabin of the civilian aircraft. It has a beautiful power on stall that takes just a little extra back stick to break and it falls through nice and level through the horizon if the stall is coordinated. The power off stall is quite docile also, but there is practically no buffet before the stall to warn the pilot. It is not unusual to end up between 60 and 90 degrees of bank coming out of a power off stall, but it is hardly noticeable due the planes awesome roll rate back to level. Steep turns are a effortless is this quick aircraft as the plane settles right in at a 60 degree angle of bank.

The T-34 is a highly complex plane with many systems that are far from standard on any other civilian aircraft. The planes have almost no navigational equipment on board which makes cross country challenging but still quite fun. The instrument set is as old as the plane and very unreliable so IFR flight is completely out of the question, but this does not hinder its abilities as a VFR aircraft. It is great for the commercial pilot maneuvers because that was it is completely designed to do. In order to fly the mentor, a pilot must have 150 hours total flight time, and 25 hours complex time or 10 hours in type. Carelessness with this aircraft can have disastrous results. Sporty, powerful, and extremely capable this aircraft is for the pilot who just wants to have fun land at another airport and show off this airplane's awesome curves.

Built in the late 1950's as a military trainer, the T-34B has very slight modifications from the T-34A. The T-34C is what is currently used at Pensacola and is almost exactly the same as the T-34B except it has a turbine powered propeller (turbo-prop). When the 'A' model was brought to the civilian world, time was taken to get it certified for aerobatics. This did not happen with the T-34B, and although it performs just as well if not better then the T34A, it is restricted to a utility category rating (no aerobatics) and is spin prohibited.

When the T-34C's started coming online, the T-34B's were sent to various recruiting commands to give potential new aviation cadets a taste of their flying future with the Navy. Many more were sent to Navy flying clubs, or sold to civilian owners. Patuxent River Navy Flying Club has three T-34B's, all handed down from the recruiting command. Their current "Fly Navy" paint scheme is representative of the last official military duty these aircraft had -- encouraging new recruits to fly for the US Navy. When they were re-certified as civilian aircraft, the FAA mandated several changes to the T-34B, including a stall strip on the right wing, addition of a stall warning system, removal of the nose gear doors, replacing the tail fillet that had been removed from the 'A' models, and generally reducing the performance restrictions. In addition, T-34B's did not undergo spin testing as part of their re-certification. For this reason, civilian T-34B's registered as Beech D-45's (including those at PRNFC) are NOT certified for aerobatics, even though years of service demonstrated their capability in this regard.

Airworthiness Directive (AD) 99-12-02 resulted from a report of an in-flight separation of the right wing on a Raytheon Beech Model A45 (T-34A) airplane. The AD was issued as an interim action until the development of FAA-approved inspection procedures. Raytheon has developed procedures to inspect the wing spar assemblies of the above-referenced airplanes. Once a crack develops, it can continue to grow through cyclic loads such as maneuvers or gusts, even while the airplane is operating under the current flight and operating restrictions. The only way to ensure that the affected airplanes do not have cracked wing spar assemblies is through the accomplishment of this inspection and any necessary wing spar assembly replacement.

Airworthiness Directive (AD) 2001-13-18], requires flight and operating limitations on Raytheon Aircraft Corporation (Raytheon) Beech Models 45 (YT-34), A45 (T-34A, B-45), and D45 (T-34B) airplanes, requires repetitive inspections of the wing spar assembly for cracks with replacement of any wing spar assembly found cracked (unless the spar assembly has a crack indication in the filler strip where the direction of the crack is toward the outside edge of the filler strip). This AD also includes a reporting requirement of the results of the initial inspection and maintains the flight and operating restrictions required by AD 99-12-02 until accomplishment of the initial inspection. The actions specified by this AD are intended to prevent wing spar failure caused by fatigue cracks in the wing spar assemblies and ensure the operational safety of the above-referenced airplanes.



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