Trojan T28 Rebuild

This is the account of my reconstruction of my crashed Airfield (FMS) Trojan T28.  I hope you have time, because, although the damage was not that great, this was big task as there was a lot to do.

Surprisingly the motor and mount are just fine.  With the impact and shattering of the prop hub, I thought sure that something here would have been severely damaged.

Humpty Dumpty of propellers

This is what I have to start with for the propeller and hub.  I was just going to order another hub, but it was hard to find one that I could get for a reasonable price from a place that had one on hand.  Nitro planes has them for only about $5, but they never seem to have any in stock.  Other sources have them, but they are twice the price and then shipping doubles this cost again.

All fit back together

So, I decided to try to repair mine.  I saw a post from another pilot who had the same issue and he mearly used Goop glue to put his back together and replace small pieces.  I thought if he could do this and be successful, I could do it too.  My prop blades are in great shape with no chips or gouges, so no issues there, just the hub.  I started the repair process by dry fitting all the pieces together to see

Other side

how they would fit together.  Once I was happy with how they fit together, I CA glued them to hold all of the pieces together.  I did this for each half.  I also test fit the two halves together to make sure that they would still mate up.

Epoxied together

Once I was happy with the two halves, I fill the void spaces with 5 minute epoxy.  I used a narow wooden stick to made sure that the epoxy got down into these voids and filled them to the top.

When the epoxy was almost dry, I used the tip of a small flat blade screw driver to scrape off any overage and trim everything down.


Now I was ready to fit the blades back into the repaired hub.  Although the hub was still a bit distorted, it fit back together better that it did originally.

This is what it looked like when I finally got it all back together.  I was a little worried about tightening down the screws as I thought it might break everything apart again, bit this was not to be the case.


Now on to the cowling.  There was only one broke off part but everything else had to be formed back together before this part would fit properly.  So, I fit the parts together as best as I could and CA glued them in place.  Then I secured everything with epoxy.  The tape in the photos served two purposes.  One was to hold things together and the other, to act as a glue dam.  I glued this from the inside so that it would not show on the outside.

Once the cracks were glued up and everything was close to aligned, I was able to glue back on the air scoop piece that was broken off.

Now it's all ready to go back on.

Before the cowling can go back on the mounts need to be repaired.  The cowling almost pulled out all three of its plastic mounting points.  The picture shows the worst one.  It will take some effort to repair to get these repaired.  I started with the top center mount and used a pair of needle nose pliers to jockey it around until it looked good with the cowling.  Then I used CA glue to hold it in place.  Then I did the same with the other two taking care to stuff any loose foam bits back in.  Once all three looked good and were secured with CA, I used hot glue to fill in the gaps and secure them even more.

Next, on to the tail sections.  Both the rudder and elevator movable surfaces were broken off and so they needed to be put back on.  Fortunately, there was no serious damage and the hinges were the only thing affected.  The rudder was easy and only needed the plastic spike hinges glued back in as they pulled straight out.  I used Goop as it gave me time to work and would not cause any serious issues if it got on the hinges.

 For the elevator surfaces I used these really cool paper hinges that I thought I would never use.  But, they were what I had and so decided to try them out.  They worked great and now I love them.  Check out my video and just see how easy they were to install.  All that is needed is a hobby knife, the hinges, and CA glue.

In this video I show the basic installation steps for these hinges.  I started with the movable surfaces. Since these used molded foam hinges, I had to start by trimming away all of the old hinge material.  This actually helped me in locating the hinge line and made for a good guide to follow.

This video shows more detail in how the hinges go together and how they are glued up.  The hinge material is made of a fiberus material that will wik the CA glue into the slot and make for a good bond.

You can see at the end of this video that even with the glue in the hinge material, they still move quite well.  I will be using these when ever I need a hinge where tape will not suffice.

Here is a photo of the ailerons fixed back up with the same paper hinges.  At first glance the wings looked fine but on closer inspection the aileron hinges on both sides were found to be badly cracked.  I just cut them the rest of the way off, trimmed the excess material, and repaired them just like the elevator.

Clevis repair

One of several repaired clevis

I had several clevises that broke.  At first I was going to just replace them but I had problems finding the right ones.  My LHS did not have a decent selection of them and online it was hard to tell for sure what size they had and if they would replace what I needed.  So, I decided to just repair what I had.  I started by trimming off the remains of the pin. Then I used a small drill bit to make a hole where the pin was.  Now all I had to do was to bend a trim a piece of paper clip to fit.  A small piece of fuel line is all that is needed to keep everything secure.  I have since found out that this is a common way of doing clevises.

Decal distorted by a fracture

Fracture can be seen here

 On to more fuselage damage.  This was not obvious for while, but there was a fracture across the fuselage above the back edge of the wing.  I noticed this because of the decal distortion (stretching).  Looking further revealed the fracture.  Since it wasn't that deep I repaired this by opening it up enough to squirt CA glue in and then close it down.  This seems to have done the job and it is holding well.

Front corner landing gear box damage

Another view of the damage

Doors and linkage broken free

What turned out to be the worst damage was the front landing gear.  The gear was broken, just flopping around, both doors were broken off, linkage was broken, and finally the landing gear box was cracked in the front and pushed back.

I started by removing all the broken parts and landing gear.
Fixing the box required using a needle nose pliers to pry on the bent surfaces until they fit back together.  I did this by inserting one jaw of the pliers down in between the plastic box and the foam.  The other side jaw was then inside the box.  I pushed them down until the tip was right at the bend.  I then pried back on the plastic until the pieces were back in alignment.  Then I used glue to hold everything in place.

Landing gear removed

Opened up showing
broken trungeon

 Now I needed to repair the broken landing gear.  This required the removal of the four small screws holding it all together.  This revealed the motor, electronics, and moving parts.  This gear works by moving a bar back and forth on a screw shaft rotating the gear itself.  The pawls on this pivoting part (trungeon?) were broken off.  Fortunately I had another one from the defective landing gear it originally came with.  I pulled this one apart and removed what I needed.

Part replaced and
ready to go back in

There was one issue with this and that was that the replacement piece was not intended for steering gear but for the shaft to be held in tight.  To resolve this I needed to drill out the strut hole so that it would pivot for steering.  This was easily done with my drill press and I carefully drilled out the plastic and brass to enlarge the hole.  Now I only needed to put all the pieces back together being careful to get all the pieces lined up and keep from pinching the wires.

Making sure the wires aren't pinched

You can see from these photos that it all went back together and now I have a functioning front steerable landing gear again.

Going back together

All back together

OK, the following video is a little lame, but what ever.  I was holding the camera and doing the servo tester at the same time.  Yeah, I could have used a tripod (I do have one), but I was in a hurry.  Any way, it still shows that the landing

gear works!

Pin replacements

Closer view

Next, on to the doors.  The obvious damage to both was that the servo horns were both broken off.  Fortunately one was still hanging on and I found the other.  These were glued back in place with a little CA glue.

Less obvious was the loss of the hinge pins on one end of each.  At first I did not know what to do.  I thought I was going to have to purchase new ones.  Then I got the idea, why don't is just make new ones?  I shaved the ends off flat and then drilled a hole where they used to be.  Then I carved down a piece of bamboo skewer and press fit them in.  These came out so nice I did not need to use any glue.

Covers installed

Now all was repaired and ready to go back together.  It took a little doing, but I got everything back in place.  Not easy to do with my fat fingers (not as dexterous as I used to be).

Ready for assembly

Everything is all fixed now and ready to be re-assembled.  The picture at the right shows all the repaired parts.

Please ignore all of the other stuff on the table

OK, was that enough for everybody?  I know it was for me!

Now I'm at that usual point of waiting for the right day and weather to go out and fly again.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

Airfield T28 Trojan Maiden Flight

I have this beautiful new new Airfield T28 Trojan and I finally have a chance for it's maiden flight!

I feel that I should note here, before I go on, that I have discovered that the Airfield name is actually a re-brand by Nitro Planes of FMS products.  Not that that's a bad thing, just that FMS T28 enthusiasts are included too!

Its Easter weekend and I will be visiting my folks near that cool park and the weather is expected to be great for flying.

Look at all those wires

We start packing for our trip and I realize that this plane is huge and would not fit in the trunk of my car (Mazda 3).  It wouldn't be so bad, but this plane is not made to be taken apart like most planes.  There are four screws that bolt the wings on from underneath.  This isn't so bad except that there are a million wires that come from the wings into the fuselage!  OK, OK, there are 5 sets of wires from one wing and 6 from the other (landing gear door, landing gear, flaps, ailerons, and wing lights) and not a million.  These are routed through small openings that make dis-assembly/assembly difficult and something to be avoided at all costs!  OK, I'm being dramatic again, but this is not trivial.  As it would happen, I did end up unbolting the wings, separating them, and disconnecting all of the connections for the servos and lights to get this big plane to fit.

Wow, this really made me think that I need to take transportation into account with planes in the future, and explains why serious RC pilots have trailers.

Once we arrived (we were early for once) I unloaded the plane into my Dad's workshop and started assembly.  Of course this was not until after we greeted them, brought in our dinner contribution, gifts for recent birthdays, and visited a little.  I'm not that crazy focused on RC planes.  Now I only had to wait for the meal to be over and for all of the other guests to leave!  I have to say that I did not really want that meal to be over because my Mom made this lamb that was to die for (hm... not sure that was worded appropriately).  Any way, it was really good.

Hooking up the battery

Snapping on the cockpit

Testing the throttle

Finally everyone is gone and I still have 45 minutes before we also need to leave.  Off to the park.  We arrive at the park.  I have to thank my daughter who rode in the back seat with the airplane tail in her face (I also have to thank her for being my photographer).  There is about a 5mph breeze, but this shouldn't be an issue.  We get the plane out and I get it setup.  Wow, it sure looks good sitting out there on the dirt runway!  I tested all of the control surfaces, I tested the motor, and then I taxied the big Trojan T28 out and around the runway.  I let her sit there for a bit off to my left facing into the breeze, giving me time to collect my courage.

Ready for take off

Leaping into the sky

I gave her full throttle and hoped to keep her straight.  Half way down I could see her wanting to take flight.  I gave her a little elevator and she shot straight up into the air.  Wow, beautiful!  I struggled to level her out and bring her around as the controls are a lot touchier that I'm used to.  Watch out, this thing can really snap around!  I eased up on the throttle and  pulled in the landing gear as I made a big loop around the airfield in front of me.  I'm just now thinking that I should start working with the trim.  I go for another loop but this time decide to try turning away from myself as I'm coming across the back field.  At this point she is downwind and about 100 yards off to my right at about a 45 degrees.

It hit about 10ft back

Dad and I assessing the damage

This is where things go terribly wrong as suddenly I feel that I have no control!  I had given more power, but she is not going any faster!  I gave her up elevator, and she is not climbing!  I gave her left and right aileron and she is not banking!  The next thing I know is that my beautiful $280 Trojan T28 is headed straight for the ground!  At the last moment she started to respond the my elevator command and pulled up just enough to avoid drilling in!  Pieces flew just before that terrible WHUMP sound reached us.  Nothing left to do but start that dreaded walk over to see what was left.

Still assessing the damage

Point of impact

Small pieces everywhere but the fuselage was intact!  So, this was bad, but not as bad as I anticipated.  We collected all the parts putting them in a bag.  Took the wing apart again and loaded it up, in the trunk this time.  No need for careful placement and handling.

Next post I hope to feel well enough to review the extent of the damages and reconstruction.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.

Happy Birthday To Me!

So not enough candles.

So, it's my birthday (well a few days ago) and it was a big one, and my wife, the understanding and sweet wife she is, said that I should order the RC airplane I've been wanting for some time!  Now I've been pining for one of these since I first saw one over a year ago.  The plane I saw was a T28 Trojan (Parkzone).  I just loved the look and size of that plane.  And now, my wife was telling me to go buy one! Woo whoo!

On Sunday, I started reviewing all of my options for a T28.  First off I have to say that I was not interested in the small versions (800mm).  I wanted a big one!  After reviewing the Durafly (1100mm and retracts), Parkzone (1120mm), Dynam (1270mm and retracts), and Airfield (1400mm and retracts) models, I chose the big one, the Airfield, from Nitro planes.  Now it was by far the most expensive (about $280 including shipping), but aside from being the biggest, it had the coolest features.  These include lights, sequenced landing gear and doors, flaps, cowl flaps, and a 2.4GHz 6 channel transmitter!

Now I'm really excitted!

Was hoping there would be a big
picture of it on the box.  Oh well.

On Monday, I signed up for an account and ordered my birthday present.  By the end of the day, my order was processed and ready for shipping.  By Wednesday, it was on my doorstep!  Granted it only had to go from LA to Sacramento (both in California), but still, I only selected the base UPS ground shipping.

With the top off

All of the big parts laid out

Nice battery even if the charge cable
is a little short.

Now I did order the RTF version (mostly because they were back ordered on the ARF), but it is anything but RTF.  After about 2 hours I had it together with the glue drying (rudder and elevator need to be glued together) and all of the servo connection hooked up.  I guess the RTF part is that I had everything to fly, including the battery and radio.  I only needed to assemble it and charge the battery.  This thing is a monster!

The beast, all put together.

Now I'm all ready to fly and waiting for good weather.

Soon I'll have an update on how it flies and hopefully not one on how it crashes.

Thanks for stopping by my blog.  Please feel free to post comments, good or bad, and be sure to come back and check for future posts.