I have been trying to build my own indoor 85mm tiny whoop that can get 7 minutes of flight time ever since iFlight built the Alpha A85. The best I ever got is about 5:30min on a BetaFPV 85x frame. So, I broke down and bought a brand new iFlight Alpha A85 from an online store to see what made them better. To my surprise, I still could not get anywhere near the 7 min flight times. But I must admit, I really like the build quality of the iFlight Alpha A85. It is a well thought out design and easy to work on. But there is one major flaw and I think it is because they can save on assembly time. The motor wires come out from the inside of the prop guards. Make sure you keep a close watch on the motors wires because the props can cut them up. Buy doing this, they can solder the motors to the AIO FC before they mount it to the frame. If they did it correctly and ran the motor wires from the bottom side of the prop ducts, they can only solder the wires after the motors are mounted.

About a week after getting the iFlight Alpha A85, I ended up selling it to a friend. Then I decided to build my own A85 because I had some spare 1204 motors and Caddx Nebula. Plus, I wanted to try any build my quad lighter than iFlight.

I went with the BetaFPV 1204 5K motors because I had a lot of spares and the HQ 2” props fit very snug on the props shafts without needing additional screws (trying to save some weight). After trying out the 1303 motors which comes stock on the Alpha A85, I notice I did not need any more power when I’m flying indoors. But I have to say that the 1303 motor ran a lot cooler in comparison to the 1204.

As for the Flight controller, I used the same iflight 20a AIO board that the A85 has. It is kind of expensive in comparison to some of the other 20a AIO boards, but it will fit perfectly without any modifications. Most of the other 20a TW boards are slightly larger and has a side mounted USB plug.

For some odd reason, I did not like the BF4.2 tune that it came with. So, I used my own tune and also ran JESC firmware on my ESC so I could enable Bidirectional Dshot. I included some screen shots of my BF settings in the image gallery below.

If you did not have all the misc. parts as I did, you are better off getting the kit because it is cheaper that way. I also found it interesting that the replacement fame kit comes with tons of hardware and even a carbon fiber brace. I did not use the brace because of the additional weight. I do not think the brace is necessary because it seem to fly perfectly fine with out it.

Outdoor flight:

Indoor Flight