3. E-flite Carbon-Z T-28 Assembly Log (Updated 2/28/2016)

1/14/2016 – Placed the order today from Horizon for the PNP version.

1/15/2016 – Order shipped – scheduled for delivery on the 16th.

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1/16/2016 –  Plane arrived in a giant box and in prefect shape.

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1/18/2016 – Typical Horizon Hobbies packaging with not a single dent or scratch.

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No tools are provided with the kit, but only minimal tools are need to assemble the plane.  Just a 2mm, 2.5mm and a 3mm hex driver.

Following the directions, the first assembly steps are the tail feathers.  Insert the vertical stabilizer assembly with integrated rudder and horizontal stabilizer servos.  Attach from the bottom with 2mm hex bolts.

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The horizontal stabs are supported by a fiberglass tube and inserted into the plastic retainers that are molded into the vertical stabilizer assembly.

The stabs are a tight fit into the retainers so align the stab and start to press into the retainer using you thumb nail to work the stab foam into the lip of the retainer.  Working from front to back, keep pressing until the stab is completely seated.  Attach from the top with 2mm hex bolts.

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Last step is to attach the Z-bend control rod to the elevator. (Not pictured)

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There are a lot of comments on various Carbon-Z T-28 forums regarding the size of the supplied control rods.  I don’t know what size they are but I don’t feel they need to be replaced as others do.

Moving on the wing is next.  Using a fiberglass and a carbon fiber tube slide the wing halves together and insert two plastic wing joiners.

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The joiners just rest in place in the wing and are used to attach the wing to the fuse using four 3mm hex bolts.

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I was pleased to see E-flite labeled motor and ESC.  Earlier reports mentioned that these were non-labeled parts and drew suspicion on quality.

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The motor is attached to the plastic firewall using four 2.5mm hex bolts.

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This completes the major assembly pieces.

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The electronics are next and since this is the PNP version I need to install a receiver.  I’ll be using the same receiver I’ve used in the Carbon-Z Cub, a Spektrum AR610 DSMX 6-Channel Sport Receiver.

What I believe is the biggest issue or concern with not just the T-28 but any significant sized electric plane with retracts is the receiver power method.  The stock power setup uses the flight battery through a BEC  built into the ESC to power the receiver, which also distributes power to the retracts.

Previous experience as well as documented T-28 crashes point to the concern of retract issues burning out the BEC  or draining the flight battery when there is a physical or electrical issue with the retracts.

I plan to use a power method that isolates the retracts from the flight battery eliminating any retract issue from affecting the receiver power.

I’ll simply be using a “Y” connector servo lead, a switch harness and a 4.8v battery. The “Y” connector servo lead will split the retracts between the receiver and retract battery.  The lead going from the receiver to the retracts will have the power wire disconnected so only power is being drawn from the retract battery and not the flight battery.

Electric Retract Power Option

1/23/2016 – Just waiting for the Turnigy 5000mAh 6S 30C batteries to arrive from Hobby King, should be here next week.

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These batteries need an adapter to connect to the E-flite ESC.  Hobby King sells an EC5 to 5.5mm bullet connector adapter.  Keep in mind that if this is your first high voltage/capacity battery use, you might need a 5.5mm bullet adapter for your charger as well.

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1/29/2016 – Received the batteries and they are puffed.  Working with Hobby King to get replacements which will probably take two weeks to get them.

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2/7/2016 – Hobby King is replacing the batteries and they were shipped on the 6th.

2/12/2016 – The replacement batteries arrived in good shape and both charged to capacity without any issues.

Bench tested the retract power isolation as diagramed using a regular servo in place of the retract, in case there were any major issues, and it worked perfectly.  Next step is to install the remaining electronics and get her to the field for the maiden.

2/13/2016 – Installed the electronics and tested the nose wheel retract and it worked perfectly.  One last test with the plane fully assembled, balanced and trimmed and then off to the flying field.  CG was obtained with the back of the battery touching the fuse.  I’ve watched several videos and saw the same battery location.

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2/21/2016 –  Finally had the time for a maiden flight.   Tracks pretty straight and with just a bit of elevator takes offs are very gentle and scale like.  No issues in the air, a few clicks of up and right trim and that was it for hands off.  Retracts worked as they should.

When landing, since this is a heavy plane she carries a lot of speed so you need to adjust the approach accordingly.  After the gear check pass, deploy flaps, don’t gain altitude and keep the speed as slow as you’re comfortable with so you don’t stall on the final turns.  Being a tricycle gear, the plane is sensitive to touching down with to much speed.

Overall a nice flying plane.  High speed low passes look great with the gear up and the big prop and motor make a nice noise.

I’ll get some field pictures next time.

2/28/2016 – Grabbed a shot at the field today.  This is a really nice flying plane, no bad habits and high speed low passes look great.

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