• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

Scaled up and Redesigned Explorer for FPV

#1
I recently built an FT Explorer for the sole purpose of flying FPV. I liked it and it flew nice, but there were a few things I wanted to change. So I decided to design something from the ground up that incorporated the things that I liked and the things that I thought would make it better.

My goals:
- easy to hand launch
- smooth flyer
- able to carry a large battery
- room for flight controller (I use Vector)
- sturdy airframe that I wouldn’t worry about stuffing expensive electronics in.

I Used SketchUp to make my design. I incorporated a couple nice features that I’m very happy with.
- There is a removable module that holds the receiver, flight controller, video transmitter, and current sensor. This will let me change the design around later and move the electronics setup easily from plane to plane.
- I also made a removable battery tray that enables me to find the perfect CG for a given weight battery. Once established, I remove the battery by simply sliding the tray out and charging the battery in the tray. With multiple trays I can swap batteries in seconds and always get a perfect CG. The tray is long enough to provide huge flexibility in battery placement.
- I decided to go with a twin engine setup since I wasn’t very happy with the flight characteristics of the pusher setup on the Explorer. I basically copied the Sea Duck wing and designed motor pods instead of the booms on the SD. I also added some ply on the spars for a little added strength.

The end result is beyond my expectations. The plane balances perfect with a 5100 mAh battery right in the middle of the tray. It takes off with just a very light toss and flies straight and level with zero bad tendencies. The counter rotating props eliminate any torque roll and the plane gently climbs out as it leaves your hand.
Once up in the air, the plane flies super smooth. The larger size helps out here I think although I haven’t weighed it yet.

Here are some pictures. It’s not super pretty but it’s super functional if you are looking for a fun FPV plane!!
on the ground ready to fly:
4959EBF6-2532-4728-8202-03BE463AB806.jpeg


Here is a side by side with the Explorer as a size comparison
A2C7582D-BCBF-4C59-ACDC-443C18829AC3.jpeg

Here is the battery tray sliding into its slot:
64051AFC-045D-4F80-93FE-54CC6EC77872.jpeg

And a screen capture of the launch
784D5B96-0B97-467F-898D-DFBCD58067F7.png


I have a short video of the launch I’m uploading now. I also have some DVR footage from the first few flights that I need to edit. The aerial footage was so good I decided to order a Runcam Split so I can get some good HD video.
Very happy with how this came out!
 
Last edited:

b-29er

Well-known member
#2
Man that build looks clean! I like it. My only question is on the airfoil, how does a foldover perform in terms of drag and efficiency?
 
#5
Oh my goodness, that looks awesome! With a battery that big, how long does it fly? I flew a normal Explorer for an hour and 28 minutes off of a 5200 3s, but you could easily fit a second battery in there is looks like. You should make that a long distance plane.
 
#6
Man that build looks clean! I like it. My only question is on the airfoil, how does a foldover perform in terms of drag and efficiency?
Thanks! I’m sure there is a much better airfoil I could use but in an effort to keep things simple I used a wing that I knew flew well. And it does fly very well with this wing.
 
#9
Here is a short clip of the maiden hand launch. There were some strong winds above the tree tops so it gets bounced around a bit but you can see how easy the takeoff is.

 
#10
Oh my goodness, that looks awesome! With a battery that big, how long does it fly? I flew a normal Explorer for an hour and 28 minutes off of a 5200 3s, but you could easily fit a second battery in there is looks like. You should make that a long distance plane.
I haven’t flown for duration yet since I’m still fine tuning the Vector, but with the 5100 3s pack I’m guessing just over 30 minutes. (The price of having twin engines) I just picked up a 6200 (lower C rating) pack that weighs about the same. I’m sure this plane will easily fly with two of those and the battery tray will hold them.
 
#11
Update!
I finally had a chance to take the plane out for a quick flight to see how well the Vector worked and do some tuning. Although I have some work to do with getting the Vector settings right, the plane flew amazing. I decided to mount a Runcam Split 2 on the nose with pan and tilt so Ill be able to get better video than the DVR recordings. I'm also redesigning the nose a bit since it is a bit porky. Here is what I came up with:
IMG_0010.jpeg

IMG_0007.jpeg

I still need to close the front up in such a way that I can still slide the front on over the camera... working on it.
Here are what all the parts laid out in Sketchup look like. Still need to go back and re-learn how to make PDF's and turn them into plans.
Untitled.jpg

Sketchup view.jpg
 
Last edited:
#13
Update!
I finally had a chance to take the plane out for a quick flight to see how well the Vector worked and do some tuning. Although I have some work to do with getting the Vector settings right, the plane flew amazing. I decided to mount a Runcam Split 2 on the nose with pan and tilt so Ill be able to get better video than the DVR recordings. I'm also redesigning the nose a bit since it is a bit porky. Here is what I came up with:
View attachment 115302
View attachment 115303
I still need to close the front up in such a way that I can still slide the front on over the camera... working on it.
Here are what all the parts laid out in Sketchup look like. Still need to go back and re-learn how to make PDF's and turn them into plans.
View attachment 115304
View attachment 115316
This looks amazing! Were you ever able to get pdf plans available?