Monday, December 18, 2017
Home » Product Reviews » E-Flite T-34 Mentor 25E ARF

E-Flite T-34 Mentor 25E ARF

Fly This Classic Military Trainer This Weekend

For nearly 60 years, the T-34 Mentor has been used as a primary military trainer for both the US Military and several air forces and navies throughout the world. The Mentor was a private venture designed by the infamous Walter Beech (Beechcraft Aircraft) and presented and marketed as an economical replacement to the North American T-6 Texan in the late 1940s. Once accepted, production of the first A models began in 1953 with a Continental 6-cylinder 185-horsepower engine. Interestingly, it was only a third the horsepower of the T-6 but had a much stronger structural G loading of +10g and – 4.5g. It wasnt until 2004 that the FAA reduced the Genvelope of the Mentors to +6/-3g after a series of in-flight structural failures. In all, over 1900 piston-powered T-34 A and Bs were produced. Although a prototype jet version of the Mentor never went into production, the Turbo-prop T-34C Turbine Mentor was designed and produced until 1990. The Mentor has now been nearly phased out and replaced with the T-6 Texan II. The Mentor is available to the civilian market and is an absolute dream to fly. The Lima Lima Flight Team, Dragon Flight and Julie Clark all use T-34s

SPECS
PLANE: T-34 Mentor 25e ARF
MANUFACTURER: E-flite
DISTRIBUTOR: Horizon Hobby
TYPE: Sport scale electric warbird
FOR: Intermediate pilots
WINGSPAN: 55 in.
WING AREA: 545 sq. in.
WEIGHT: 81 oz.
WING LOADING: 21.42 oz./sq. ft.
LENGTH: 44 in.
RADIO: 4 channels required; flown with a JRX9303 2.4GHz transmitter, Spektrum AR6200 6-channel receiver, 5 JR Sport ST47 servos
POWER SYSTEM: E-flite Power 32 brushless outrunner motor, APC 12X8e prop, E-flite 60-amp Pro Switch-Mode BEC speed control, E-flite 4S 3200mAh battery.
TOP RPM: 9,350
DURATION: 7-9 minutes depending on flying habits
MINIMUM FLYING AREA: Ball field/RC club field
PRICE: $199.99 ARF or $449.99 in the ePTS RTF version
COMPONENTS NEEDED TO COMPLETE: Motor, ESC, battery, 4 servos (5 servos if using flaps), prop, 2 6-inch extensions and 1 Y-harness (only needed if using a non-computer radio).

SUMMARY
I have yet to assemble and fly an E-flite airplane I didnt like. The T-34 Mentor 25e ARF from Horizon Hobby is no exception. The construction is lightweight yet very strong and durable. The fixed gear is rugged enough for nearly any grass runway cut short and the flight characteristics resemble everything from an easy-to-fly trainer to an all out aerobat.
FULL THROTTLE POWER:43.05 amps, 635 watts; 7.88 W/oz. for their air show acts. Now you, too, can fly the T-34 with this great electric version from E-flite.

THE MODEL

Offered in both an RTF ePTS and the reviewed ARF version, the T-34 is constructed of balsa and light ply and expertly covered in UltraCote. Assembly will generally take just a few hours and can be ready to fly in a couple short evenings. I found no surprises during the assembly of the ARF version and have only a few recommendations. The RTF version is available for $449.99 and comes completely assembled with all required accessories in the box. These accessories include a Spektrum DX6i 2.4GHz computer radio, E-flite Power 25 outrunner motor, 11.1V LiPobattery and Li-Po balancing charger. During the first few steps of the manual, you are instructed to assemble both the horizontal and vertical tail surfaces. Although they tell you to secure the tail in place, I suggest leaving the nylon lock nuts loose enough to adjust the tail and square it with the wing tips once the wing is in place. Ideally, you want a perfectly square airplane (symmetrical) and I found there was just enough slop in the tail to possibly put it nearly 1/2-inch out of square. This is not detrimental to the overall flying qualities but it will cause less than perfect slow speed and stall characteristics.

The wing for the Mentor comes from the factory with the flap linkage installed in a fixed position. Although not needed for this airplane due to its light weight and light wing-loading, I chose to add the additional servo and utilize the flap function on my JR transmitter. Computerized radios typically offer the ability to assign the flap channel to a switch or in my case, a slider on the transmitter. The nice thing about the slider is that you can set the flaps in any position you want for the conditions, rather than the preset up, mid and down fixed positions you get with a switch.

It took me just two evenings of a couple hours each and I was ready for the field. The nice thing about using the recommended components in the manual is that more times than not, the center of gravity comes out right on the money.

For those who chose the additional performance of the Power 32, you may need to move your battery toward the aft limit of the battery tray. Even with this setup and the 4S battery pack, the wing loading came in at just under 21.5 ounces per square foot. Trust me, it still likes to float.

TIPS FOR SUCCESS

There are very few tips for success needed here. This is another winner from E-flite. Take your time, use thin CA to harden all wood screw holes and use the included plywood plates for standard servos. Remember to go back and tighten the tail surfaces after squaring the wing tips to the tail tips. Follow the suggested control throws listed in the manual and do not exceed the recommended center of gravity limitations. These few items will reward you with a rock solid airplane.

One thing I would like to recommend is to choose a quality speed control for your model. With five servos on board you will need either a switch mode BEC or separate receiver battery pack to supply sufficient power. The E-flite controller I used can supply a continuous current of 2.5 amps at up to 6S, so it easily covers the needs for the T-34. Other options will likely require the additional hassle of an aftermarket BEC or another battery to power the radio.

AIRBORNE

The maiden flight of the new T-34 was at our freshly-cut grass field. The Power 32 and 4S 14.8V 3200mAh battery had the airplane airborne in less than 10 feet. With power reduced to approximately 65 percent, very little trimming was necessary. Two clicks of right rudder and one click of up elevator were all that were needed. The ailerons were right on. I left everything on high rates to discover its flight envelope. Power-off stalls saw a slight drop from the left wing, while power-on stalls were more pronounced with the left wing dropping more aggressively. The moderately sized rudder has quite a bit of power, and readily allowed flat turns with opposite aileron to keep the outer wing down. Both upright and inverted spins, as well as normal and flat spins were all easily accomplished. All other basic aerobatic maneuvers were no problem for this docile trainer. Given the wing loading, its not surprising that the T-34 glides very well. Knowing the stall and glide characteristics of any airplane will teach you a lot about how it will act and react in the pattern. Approaching and flying the downwind leg at one third throttle is a good place to start. Keeping the pattern somewhat close and slowly reducing power to nearly idle on final proved best. The sink rate can easily be controlled with power. Finding the groove with this airplane didnt take long. Once I made the runway, a small amount of back pressure rewarded me with a picture perfect landing the majority of the time.

I have had the opportunity to fly the Mentor in both light winds and when gusting to 15 mph. It is extremely stable in all regimes and is a pleasure to fly. I hope a retractable gear version is in the works.

CONCLUSION

The T-34 Mentor design is remarkable. With its astounding scale detail, rock solid stability and awesome performance with either the Power 25 or 32, this sport scale Mentor from E-flite is a winner. While not intended for the beginner builder or flyer, someone with intermediate building and flying skills will find this airplane a true pleasure. It has the performance and stability of a much larger airplane yet is small enough to fit in the car fully assembled. I am very pleased.

Links

APC Propellers, distributed by Landing Products, www.apcprop.com, (530) 661-0399
E-flite, distributed exclusively by Horizon Hobby Distributors, www.e-fliterc.com, (800) 338-4639
JR, distributed exclusively by Horizon Hobby Distributors, www.jrradios.com, (800) 338-4639
Spektrum, distributed by Horizon Hobby, www.spektrumrc.com, (800) 338-4639