Grumman S-2 Tracker Foam Board Build

vhandon

Active member
I have built many FT planes, a few from kits but most from just the plans. I decided I wanted to build something different and it had to be something rare. I first thought of a building a Boeing 247 and I still may build one in the future. The obvious choice for me though is the Grumman S-2 Tracker. I have a special connection with this plane since my father was an electronics specialist and was part of the crew on one in the Navy. As soon as I find a picture of him with the plane I will post it. I have only found a few of these that have been built and flown and they were all large high-end balsa builds. I plan on using mostly foam board and achieving scale looks (from a distance).

s2small.jpg


I found good plans for a 63" wingspan balsa build that I am using as my template. I think I can power it with the FT Twin Power Pack C.

GrummanS-2Tracker.jpg


I am hoping to have flaps and retracts but static landing gear would be fine as well. If anyone one has a suggestion for retracts that do not come out of China please let me know. If not, I will have to order them soon so I can get this thing ready for Flite Fest Texas.
 

vhandon

Active member
Good find on the "Mini retract unit for RC planes" thing. I will be printing a copy of that one today. I am on thingiverse a lot but missed that one some how.

I already printed a copy of "Landing gear retract rc V2" but I am not in love with it.

Got a chance to print the Mini Retracts and I think they came out nice. It was a little work to clear out the built in printing supports, had to pull out the Dremel. I would prefer that the model leave those out and let the slicing software add them but just a minor nuisance.

LG1.jpg LG2.jpg LG4.jpg LG3.jpg

These are definitely a contender but I also found a nice set from MotionRC that appear to be the right size and reasonably priced.

https://www.motionrc.com/products/flightlinerc-1600mm-f7f-nose-landing-gear-flw3021081#qa-tab
https://www.motionrc.com/products/f...ding-gear-left-flw3021082?variant=30792037516
https://www.motionrc.com/products/f...ing-gear-right-flw3021083?variant=30792038476

I guess it would not hurt to have both on hand and use the set that fits the best.
 

vhandon

Active member
Build Update 1

It rained all weekend so instead of flying at a near by event I stayed in and worked on the Tracker. I made some good progress. Hopefully I can keep up the momentum and get it built in the next few months.

Fuselage skeleton and and Tail:
S2-Fuse-Tail1.jpg S2-Fuse-Tail4.jpg

Tail closeup:
S2-Fuse-Tail2.jpg S2-Fuse-Tail3.jpg

Inside the Horizontal Stabilizer:
S2-Elev1.jpg

I had a few unknowns going into this project. Some I have think I have answers for and some that are still up in the air:
  1. How do I want to address the separate elevator surfaces? Should I use two servos or just split the control rods and use one?
  2. How do I want to finish the outside? Paint or some type of wrap or coating?
  3. How to mount the wings? They need to be removable for transport.
  4. Should I install the electronics under the wing or from a hatch in the bottom that is accessible when the wings are installed?
  5. Finding the CG? I never seem to get this right on the first attempt.
Think I will tackle the wing next.
 
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vhandon

Active member
Build Update 2

The rain continues so the build does as well.

Took me three attempts to get the wing exactly the way I wanted but I am happy with the results. Everything is fitting together well so far.

S2-WingInternals.jpg S2-TestFitWing.jpg

Received all the electronics except the landing gear tonight so I will try to get them installed this weekend along with all the control surfaces. And maybe clean up my work-space if I have time.
 
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vhandon

Active member
Got a chance to print the Mini Retracts and I think they came out nice. It was a little work to clear out the built in printing supports, had to pull out the Dremel. I would prefer that the model leave those out and let the slicing software add them but just a minor nuisance.

View attachment 114358 View attachment 114359 View attachment 114361 View attachment 114360

These are definitely a contender but I also found a nice set from MotionRC that appear to be the right size and reasonably priced.

https://www.motionrc.com/products/flightlinerc-1600mm-f7f-nose-landing-gear-flw3021081#qa-tab
https://www.motionrc.com/products/f...ding-gear-left-flw3021082?variant=30792037516
https://www.motionrc.com/products/f...ing-gear-right-flw3021083?variant=30792038476

I guess it would not hurt to have both on hand and use the set that fits the best.

I went ahead and ordered the retracts from MotionRC. They are very nice but they are too big for this project. I knew I was taking a chance without more precise measurements but I am sure I can use them on a future project and i'm only out about $70.

MotionRCRetracts.jpg
 

vhandon

Active member
Build Update 3

Since the retracts are not going to work out and I don't trust the 3d printed ones without real testing I decided to install fixed gear. I was also able to get all the electronics and control surfaces installed. I reinforced the wing and figured out the mounting system.

Servos2.jpg UnderWing.jpg

Front Steering installed.
FrontGear.jpg

Here it is standing on its own three wheels. I will need to add a tail wheel or drag.
FullLow.jpg FullHigh.jpg

I learned a new term when researching how to connect the split elevator surfaces to one server. In my short time in the hobby I had never heard of a Triple Rod Connector. I found some online but not at any local hobby shops. I did, however find something that would work at the local hardware store. Found these in the electrical aisle, a package of two for $7.
TripleRodConnecter.jpg

Hope to get the motors mounted and start skinning it this weekend.
 

vhandon

Active member
Build Update 4

Finished skinning the entire plane and mounted all the motors. Just realized I did not test the motors yet. Hope I left enough room to get them out if there is a problem with either one. I think I lucked out with the CG, two 2200 3s in front of the wing seems to balance perfectly. Without the batteries the plane weighs in at exactly 1300 grams. I think the twin C power pack should have enough power to get it in the air. All that's left is a lot of sanding, filling, sanding, filling, sanding, then paint. My other hobbies include automotive paint so I am used to the sanding and filling associated with body work.

backleft.jpg front.jpg left.jpg leftlevel.jpg lefttop.jpg righttop.jpg
 

DamoRC

Elite member
Mentor
Build Update 4

Finished skinning the entire plane and mounted all the motors. Just realized I did not test the motors yet. Hope I left enough room to get them out if there is a problem with either one. I think I lucked out with the CG, two 2200 3s in front of the wing seems to balance perfectly. Without the batteries the plane weighs in at exactly 1300 grams. I think the twin C power pack should have enough power to get it in the air. All that's left is a lot of sanding, filling, sanding, filling, sanding, then paint. My other hobbies include automotive paint so I am used to the sanding and filling associated with body work.

View attachment 115432 View attachment 115433 View attachment 115434 View attachment 115435 View attachment 115436 View attachment 115437

Excellent work!

DamoRC