Freewing F9F Panther 64mm EDF Jet 4S Flight

In 1080p 60fps - Here is the raw uncut footage of my Freewing F9F Panther 64mm EDF Jet, modified for 4S power (Click below for additional video info).

Powered by a Tattu 4S 1800mAh 75C lipo, weighing in at 193 grams and pushed as far forward into the nose as possible (to accomplish this, I had to cut a segment of the front of the interior wooden frame grid, just stopping right before where the velcro straps are screwed in, so that the 4S lipo can slide all the way forward into the nose at an angle). The CG was measured at 23mm from the leading edge of the air intake (because of the additional weight of the 4S lipo, no additional nose ballast was required and I found this CG to be spot on for this model.. and I'll let my flight video confirm that). Flight Timer was set to 3:10 minutes. Flown with a Spektrum DX8 G2 Transmitter and using a Lemon RX DSMX 7-Channel Diversity Stabilizer / Receiver.

Personal modifications were as follows:

1) ZTW Mantis 45A ESC w/ 5A SBEC (for safe and durable 4S operation).
2) Slotted .057x.177 Carbon Fiber Flat Wing Spars (for added 4S structural reinforcement).
3) JB Weld 5-Minute Clear Epoxy-Coated Undercarriage (durable landing skid finish protection).
4) JB Weld 5-Minute Clear Epoxy-Coated Fuel Tank Heads (for additional skid finish protection).
5) Minwax Satin Finish Polycrylic Dual Coating (for overall airframe finish protection).
6) Foam Tac Surrounding Elevator Rod Keeper (additional safeguard against screw slippage).

The rates and control linkage setup I used were as follows:

Aileron: 70% with 32% Expo - Control rod to the outermost hole of the control horn.
Elevator: 85% with 29% Expo - Control rod to the outermost hole of the control horn.

Lemon RX Stabilizer Gain Settings:

Aileron: 8:45 O'Clock Position
Elevator: 9:00 O'Clock Position

With the success of my Freewing F8 Crusader 64mm EDF Jet 4S Project - https://youtu.be/gj2ymJQghEI, I chose the Freewing F9F Panther 64mm EDF Jet to be the next candidate for 4S modification. As it was originally confirmed by Motion RC that the stock EDF unit of the Panther (2627-4300Kv motor / 5-blade fan) is capable of 4S, I opted to keep that (like the Crusader) stock and simply upgrade the stock 30-amp ESC to a ZTW Mantis 45A ESC with 5A SBEC (FYI, the Crusader has had no issues to date operating on 4S with just an upgraded ESC and neither has the Panther).

I then focused on reinforcing the airframe to easily handle the additional stress of 4S by adding carbon fiber flat spars to the wing / fuselage joint. Using an Xacto knife, I chose a panel line to follow on each wing / fuselage joint and cut thin slotted channels running from the air intake segment of the fuselage, towards the aileron servos (see photo in video). I was then able to push the pre-cut .057x.177 Carbon Fiber Flat Strips into these channels to initially dry fit them, and then glue them in with JB Weld 5-Minute Clear Epoxy.

Next, I added a dab of Foam Tac to each side of the Elevator Rod Screw Keeper as added insurance in the unlikely yet unfortunate event that the Screw Keeper that holds the Elevator Rods slips.

The remaining modifications are simply for aesthetics. I carefully applied JB Weld 5-Minute Clear Epoxy to the center strip of the undercarriage with foam brushes (see photo in video), being patient to go section by section and follow the panels of the undercarriage from the front to the back of the fuselage, creating a long uniform reinforced epoxy strip, protecting the surface from belly landing abrasion. I also applied JB Weld 5-Minute Clear Epoxy to the wingtip fuel tank heads for increased protection. Lastly, the entire airframe has been polycyclic coated twice with Minwax Satin Finish Polycrylic, protecting the airframe from general handling and belly landings.

My Freewing F9F Panther 64mm EDF Jet (4S-modified) was actually a project I completed in the summer of 2018. I had just not gotten around to getting any flight footage, until now. As belly lander aircraft season approaches with the grass getting taller at the parks, I finally had the chance today to take my Panther out of winter hibernation for some rock solid dialed in flights (I think Mike was impressed as well). The work I put into this project had really paid off, resulting in a fast "locked-in" flying machine that's meant to last. I can't wait to get more flights with my Freewing F4F Panther 64mm EDF Jet (4S) as the days get longer and the temps get warmer.

Flight video footage taken with Mike's iPhone X on 1080p 60fps. Thanks Mike for this outstanding video capture! This is the best footage you have taken to date. :)

And as always, thanks for watching!