Greg Covey

E-flite’s sport scale re-creation of the [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFL4150]T-34 Mentor[/link] perfectly replicates the easy-going flight characteristics of the full-scale version by using a blended Selig airfoil design that yields impressive aerobatic capability without any surprises. Available in two 25-size electric-powered versions, ARF and RTF, the T-34 Mentor provides simple, straightforward assembly with plenty of the details already completed for you.

Designed for the intermediate to advanced pilot, the T-34 Mentor 25e ARF has the following features and specifications.

Key Features:[ul][*] Can be flight ready in just a few evenings[*] Balsa and ply construction[*] Blended Selig airfoil design[*] Painted fiberglass cowl[*] Genuine UltraCote trim scheme[*] Large magnetic battery hatch[*] Plug-in wings[*] Pre-hinged control surfaces[/ul]
Specifications:[ul][*] Wingspan: 55.0 in (1575mm)[*] Overall Length: 44.0 in (1110mm)[*] Wing Area: 545 sq in (34.9 sq dm)[*] Flying Weight: 5.00 - 5.25 lb (2.20 - 2.30 kg)[*] Motor Size: Power 25 or Power 32[*] Radio: 4+ channels, 5 with flaps[*] Servos: Standard size servos, JR Sport ST47 (4, 5 with flaps)[*] Trim Scheme Colors: White (HANU870), Flame Red (HANU883), Black (HANU874)[*] Prop Size: 11x8 electric (Power 25), 12x6 electric (Power 32)[*] Spinner Size: 2.25 in.[*] Hardware Included: yes[*] Speed Control : 60 Amp ESC (EFLA1060)[*] Recommended Battery: 3200mAh 4S 14.4V Li-Po, 20C or better[/ul]

Greg Covey

The T-34 Mentor parts were secured well in the box with tape and custom cardboard designs. All parts came sealed in plastic and all control surfaces were pre-installed. Even the control horns were pre-installed.

Some of the covering was wrinkled so I touched it up with a heat gun. The Ultracote shrunk very nicely!

The wings have optional flaps and both the servo bay and gear main slots are pre-trimmed. The cowl and canopy are complete along with pre-drilled holes to mount the cowl and magnets to secure the canopy. All the hardware is included.

The 28-page manual is the usual E-flite high standard with clear photos and text instruction which helps guarantee a successful assembly. The decal sheet won't be needed on this scale model.

jarih

Hi Greg.
First off all I saw your website and you have agreat collection of Elec RC Planes specially large scale.

I started flying last year and now fly the apprentice 15e really well, doing loops and rolls..I enjoy the plane every time.

I am now planning to upgrade myself, one of the planes I was intrested was T34, for the $449 it is comming with a complete package plus Dx6 system.

Since u have experience in Electric, can you suggest if this is a good plane for me, or if you suggest something else, I prefer larger planes 55inch wing span plus

Any guidnace will help, also should I get the complete system or reuse the Dx5 on the T34

JArih

Greg Covey

Hi JArih,

I think if you can fly the Apprentice performing loops and rolls then you will have no problem flying the T-34 Mentor.

The T-34 uses 5 channels instead of 6 because it doesn't have retracts. You could use the DX5 transmitter if you use the gear switch for the flaps. You really only need two positions for the flaps, on and off, so it should work fine if you decide to go that path.

I'll be posting some fuselage and power system component photos soon.


Regards.

jarih

Thanks ...
So which means I need only the ARF version and buy the servos, motor and esc and reciever separatly

Greg Covey

A closer look at the fuselage reveals the high quality of the design as well as the amount of pre-assembly. What you can't tell from the photos is that it is very sturdy yet weighs only 13oz. The slots for the stabilizers have the covering already removed for a clean, precise look.

The decals are pre-applied, the motor box built, and the control rod tubes pre-installed. Even the nose wheel mount has been pre-installed. Magnets are mounted to hold the canopy in place and t-nuts for the gear mains are pre-installed. The servo bays have pre-drilled holes for the JR Sport ST47 standard servos.

Greg Covey

I'll be using the [link=http://www.horizonhobby.com/Products/RelatedParts.aspx?ProdID=EFL4150&Category=Completion%20Guides&SubCategory=High%20Performance%20Set-up]High Performance Setup[/link] which includes the following items.[ul][*] E-flite [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLM4032A]Power 32[/link] Brushless Outrunner Motor[*] E-flite [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLA1060]60-Amp[/link] Pro Switch-Mode BEC Brushless ESC[*] E-flite [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLB32004S]3200mAh[/link] 4S 14.8V 20C LiPo[*] Spektrum DSM2 [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=SPMAR6200]AR6200[/link] 6-Channel Receiver[*] APC Thin Electric Propeller [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=APC12060E]12x6[/link] e-prop[*] JR Sport [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=JSP20050]ST47[/link] Standard (1.55 oz, 47 oz/in Torque) Servos[*] JR [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=JRPA215]HD Servo Horns[/link]/Arms (2)[/ul]

Greg Covey

The T-34 assembly begins by mounting the stabilizers. A few of the steps in the manual were already done so I suspect that they increased the pre-assembly after the manual was created. Note that all the control surfaces are pre-hinged and already have the control horns mounted.

Both the stabilizers simply press into position and are held in place with two 4-40 washers and locknuts. The rudder control horn is inserted while pressing the vertical stab in place. My aft tail cone arrived damaged in the box so I have requested a new one. It is a single hallow piece of thin painted plastic that screws into the rear of the fuselage.

The T-34 tail assembly procedure is as good as it gets. No glue, no cutting, simply a clean beautiful look! So far, I have only used a Phillips screwdriver and a 1/4" nut driver.

Greg Covey

When using standard size servos like my JR Sport ST47s, you need to install the servo plates with medium CA before mounting the servos. All the hardware that came with the servos was used, including the grommets, brass eyelets, and screws.

The receiver is also installed at this time. I used a Spektrum AR6200 6-channel receiver and mounted it per the manual. The excess servo leads were secured with a cable tie.

Greg Covey

Horizon Hobby was quick to send out the replacement tail cone. It simply screws into place with the supplied hardware.

Now my Mentor tail looks just right!

Greg Covey

The rudder servo uses the (JRPA215) HD Servo Arm for both rudder and steerable nosewheel control. Since the control rods are pre-bent, they simply slip into the pre-mounted plastic rods before attaching the clevis to the threaded ends.

The elevator rod is the longest one at 23.25". I did end up cutting about 1/4" of the threaded end off because it was a bit too long for the clevis. The keepers were supplied in the kit and everything else fit perfectly.

Greg Covey

The nose gear installation was simple and solid. All the work has already been done so it was easy to install per the manual. However, I did have some binding when turning the nose wheel to the right which required that I elongate the slot in the motor box.

I used a small amount of Locktite on the metal screw that secures the steering rod in the brass connector.

Greg Covey

The E-flite T-34 motor box is designed to accept either a Power 25 or Power 32 outrunner motor. When using the Power 32 motor, you need to use the included 3/16" metal standoffs. Note that the manual calls them 3/8" (5mm) standoffs but it meant 3/16". I used some Locktite on the 3mm x 15mm socket head screws to keep them from vibrating loose.

I discovered something new upon reading one of the E-tips in the manual. If you use all E-flite components (e.g. motor and ESC) in the power system, you can connect the ESC and motors wires by matching the colors and the motor will spin in the correct direction for a tractor (or puller) setup. Previously, this was always hit and miss for me which required testing the direction of rotation with a live setup. A nice consistent feature from E-flite!

The E-flite 60-amp Pro Brushless ESC was placed per the manual recommendation. I used some servo tape in the upper corner of the fuselage frame and a foam wedge on the bottom to secure the ESC. The manual recommends using the supplied hook and loop tape but I didn't want to apply it across the inside of the covering material.

Lastly, I added a few cable ties to keep the motor/ESC wires neat and secure.

Greg Covey

Since the cowl was ready to screw in place using the supplied 3mm x 12mm socket head screws, the alignment was perfect. I used the supplied red plastic spinner with an APC 12x8 e-prop. Although the backplate fit perfectly onto the collet adapter, the prop hole needed to be opened a small amount by using a 1/4" drill bit. The fit and gap of the red spinner was perfect and I had no wobble at the tip of the spinner when spinning the prop.

E-flite offers a 2.25" Aluminum Spinner ([link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLSP225]EFLSP225[/link]) as an optional scale upgrade.

Greg Covey

The JR ST47 aileron servos were installed using their own grommets, eyelets, and hardware. I used a JR Sport (JSP98110) 6" servo extension on each servo lead before routing them through the wing halves using the installed strings. All the threaded rods were pre-bent so they simply inserted into the pre-installed control horns and were secured with the supplied keepers.

Working flaps are optional on the T-34 Mentor so it comes installed with the fixed flap linkage and a flap "stay" glued to the right wing half. I'm using the flaps on my model so I installed another ST47 servo in the wing bottom after first removing the covering from the optional servo opening.

A second metal threaded Y-rod is provided in the kit so you need to swap the two clevises over from the fixed linkage. The flap servo arm hole needed to be opened with a 5/64" (2mm) drill bit and the two clevises twisted to obtain a 1/4" (6mm) flap offset when the servo was centered. Again, all the keepers were supplied.

Joining the wing panels required only inserting the main aluminum wing tube and a 5/32" x 1-3/16" aluminum pin near the trailing edge of the wing. Once the two wing halves are pressed together, they are held by a nylon strap and two 3x12mm self-tapping screws going into the pre-drilled pilot holes. At this time, you can connect the remaining flap linkage.

Greg Covey

The main landing gear press into the the wing panel and are then held by two nylon straps. Unfortunately, this great looking model does not have an option for retracts.

The final wing assembly is as easy as inserting the tab in the front of the wing into the slot in the fuselage and then secure it with two nylon bolts. The wing saddle fit perfectly against the fuselage and no alignment is required. The Mentor could now stand on its own three wheels and did not tip back without the battery installed.

Greg Covey

The battery position shown provides me with the correct CG (4-3/4" or 120mm) from the leading edge of the wing center when using active flaps. I used both the supplied hook and loop straps as well as my own industrial strength Velcro to secure the battery. The Velcro goes underneath the battery pack to keep it from sliding and the straps act as a "seat belt" to keep the pack from pulling away.

The canopy simply slides into place. It uses two prongs in the front for alignment and two magnets in the back. Although both dashboards come equipped with gauge decals, there are no pilots.

I set up the control throws per the manual and added 30% exponential function to all throws except rudder.

Suddenly, my T-34 Mentor was done!

Greg Covey

We had some nice weekend weather in upstate NY for April which gave us a chance to test fly the T-34 Mentor. Before flying, I measured the power level at 784 watts at 53 amps which settled down to 775 watts after 10 seconds. The plane weighed 83oz (5.2lbs) RTF including the 13oz LiPo pack. My high performance setup produced a very capable 149w/lb.

Team JR's Devin McGrath took the sticks and gave the Mentor a real workout. The plane was very stable in flight and could perform advanced aerobatics like knife edge passes. Inverted flight was also very stable. The fuselage did twist a bit during the knife edge pass causing the canopy to drop off. This didn't seem to affect the Mentor as much as I feared and Devin landed it without any noticeable issues. We put the canopy back on with a small piece of cellophane tape on the aft end and had no other issues.

The flaps didn't seem very effective using the recommended throws in the manual. Perhaps more flap would have a better effect on slowing the Mentor but we decided that they are not needed anyway. The plane also required a fair amount of elevator offset as it wanted to pitch up with flaps so I would recommend adding a mix in with the flap switch. Overall, the Mentor was a solid and stable performer.

We caught it all on video so I'll be posting that soon along with some more flying photos.

flying photos by "Papa Jeff" Ring

Greg Covey

The video shows the Mentor landing with and without flaps. We didn't see any difference in landing speed so perhaps increasing the flaps to around a 30 degree swing would work better. The landing gear was nice and solid. It performed well in the thick, damp grass. The Mentor needed very little take-off runway and was rock solid in every maneuver.

I liked just about everything on this T-34 design. It was a quick, easy build and feels solid yet light in my hands. The Mentor looks great in the air and flies very well. There is an upgrade for the red spinner, if desired. Additional upgrades for retracts and pilots would have been nice but the Mentor does have a nice price as is.

The E-flite T-34 Mentor is a good choice for intermediate level pilots looking to get a mid-sized scale electric airplane that can fly off grass. It has the power to perform a wide range of aerobatic maneuvers or just fly a level circuit, even in some wind.

[link=http://www.gregcovey.com/reviews/EfliteT34Mentor25.wmv]T-34 Mentor Test Flying Video[/link] (25meg)

flying photos by "Papa Jeff" Ring

rivas8409

My Feedback: (1)

I'm looking to purchase one of these T-34's. How easy is it to transport? Can the wing be removed and re installed easily as with Hangar 9's Pulse?

prebres

My Feedback: (7)

Ive had mine for 2 years. Its GReat. Wing is attached 2 screws

t34pilot

Should the elevator offset be up or down (positive or negative values) to offset for the pitch up with flaps? Just wanting to make sure I have it right before trying it for the first time.

Thanks,
Bill

t34pilot

To answer my own question: It is down elevator. About 10%?

DarrellMims

[8D]   I purchased a T-34 today and found the canopy bottom at the rear section broken thru. Not a problem just noted.I did find that it would not latch properly but I think I can solve that one. I would like it to have retracts though , might take some work to do that . Oh and had to reglue the motor box  because it was coming loose.

DarrellMims

Yesterday I got a chance to fly the T-34. Everything checked out and off to the field I went. A slight breeze straight down the runway and the first flight was off . Had a slight urge to go up so a little down trim and a few touch and Go's then a little more throttle and all of a sudden the Canopy came off . No worries just land ,put it back on and take off . First flight was great ,landings were smooth and I dont think it needs the flaps because it slows too much and they were just fine not using them . Second flight with a new battery was a short one . Checked the roll rate and a loop or two and then added some speed and climb to check out slow flight and test the flaps more. Thats when things went wrong ! The Canopy came loose again but this time the plane flipped over on it's back and headed down for Terra Firma (ground) .Luckly I had enough altitude and control was regained and I brought it around for a quick landing . I thought for sure I was about to loose another plane, I checked the reciever after it was on the ground and a steady light was showing so I dont think Brown out was a problem. Could have because it had no control at some point in the roll over but it didnt show it on the reciever.                                                                                                                                  the Fuselage has so many holes in it ,I think they could have left the ones over the wing saddle to keep it stiffer would slove some of the twist and bolt down the canopy like the SeaGull Yak 54 using two screws and tabs that fit down in the side of the Fuselage. The Plane is so light Flaps are not needed. It lands much smoother than if you put them down a knotch . A 25 motor maybe the way to go instead of a 32 because only half the power is needed ,you fly around at half throttle all the time. I hope Horizon will replace the Canopy free of charge ,I found the floor in the rear seat broken because of damage to the box during shipping . I know it's not their fault about the damage but something should have been addressed in some form of bulletin and some improved latching system for it incorporated since this plane has been out for some time.  Ths is a good plane ,it just needs some updating and let people know it has had problems and correct them .