Official Freewing 64mm F-14 Tomcat Twin 64mm EDF Jet Thread

[CraigG]

The 64mm F-14 does not do an aft CG… The other day in another thread a person said all EDFs have very nose heavy CG points in the manual. I said not all and advised to find a point that each person liked. His reply was, okay 99%…

The manual does not give a cg range, just a single measurement and fuselage mark for the cg. My battery (5200mah) is well aft in the compartment to achieve that cg and although the jet flies ok, it's a little sensitive/pitchy on landing...kind of like the cg is a little aft. I was going to experiment with moving the battery forward. The only real risk I see is maybe running out of elevator on landing. Wondering what others have found and/or tried regarding cg.

[xviper]

The 64mm F-14 does not do an aft CG… The other day in another thread a person said all EDFs have very nose heavy CG points in the manual. I said not all and advised to find a point that each person liked. His reply was, okay 99%…

It's hard to reason with someone with blinkers on.

The manual does not give a cg range, just a single measurement and fuselage mark for the cg. My battery (5200mah) is well aft in the compartment to achieve that cg and although the jet flies ok, it's a little sensitive/pitchy on landing...kind of like the cg is a little aft. I was going to experiment with moving the battery forward. The only real risk I see is maybe running out of elevator on landing. Wondering what others have found and/or tried regarding cg.

There is a very easy solution to this. Make adjustments minute. Trial and error can be tedious.

[Evan D]

Agreed, I’m usually one of the first with a plane, it’s nice when I’m not and have trust worthy suggestions.

[kallend]

X viper. I do think they land less aggressively on front gear. A small amount say 10 or 15 mm behind.. on grass 4 me anyway. But 40 mm like jon. (2 brother's ). Is to much 4 most. He is very good

He also flies with very aggressive gyro gains on the pitch axis.

[CraigG]

There is a very easy solution to this. Make adjustments minute. Trial and error can be tedious.

Agreed...just trying to take advantage of the collective knowledge on this forum. No need to reinvent the wheel if I don't have to.

[400driver]

After the failed single engine take off and subsequent flat spin , the F14 is rebuilt and ready for a re maiden this week. During my rebuild i ordered a new ESC and sent the old one back to Freewing. I connected the new one for a test and all ops normaol.
Finished the re connection and went to test all functions and found that on plugging in the ESC REV wire , one motor failed to work !!! After many hours fault finding a tearing my hair out in frustration , i found the error ! I had a bad line of programming in the EdgeTx software. In my enthusiam for multiple safety measure I had made a mistake!
I love this hobby as I am always learning something new. At least its ready to go again and have a new as a spare.
I have reverse on a switch and providing that the GEAR is down , The TROTTLE is active, it will provide a certain level of reverse. Got to love RC!

[Evan D]

Good you figured it out but if you sent the original one to FreeWing how do you have a spare?

[400driver]

I ordered a new ESC and a new plane!

[400driver]

Further update on the plane after i thought i solved the issue. All was working perfectly and i powered on the model and the fault re appeared, no motor on one side. I disconnected the REV cable to the RX and powered up again....Bingo , both engines live. I then connected the REV to CH 6 as before and now all working as intended.
On RCG i was told this is an issue with some ESC firmware that gets confused when the RX is an an uknown state, IE bfore the radio connection is established. This is because ELRS receivers do not output on the PWM ports until a link is established.
Now to solve it I have to wait till powered up and then connect reverse! Another lesson learned about RC and ELRS.
Hope this may help someone down the line.

[Fast N Light]

Further update on the plane after i thought i solved the issue. All was working perfectly and i powered on the model and the fault re appeared, no motor on one side. I disconnected the REV cable to the RX and powered up again....Bingo , both engines live. I then connected the REV to CH 6 as before and now all working as intended.
On RCG i was told this is an issue with some ESC firmware that gets confused when the RX is an an uknown state, IE bfore the radio connection is established. This is because ELRS receivers do not output on the PWM ports until a link is established.
Now to solve it I have to wait till powered up and then connect reverse! Another lesson learned about RC and ELRS.
Hope this may help someone down the line.

Every time the lipo is changed, the reverse signal lead needs to be unplugged prior to power and then plugged back in? Cannot be the design intent or end user expectation.

[400driver]

It is a bit strange but thats the only way to get it to work, or have a small RX battery pack to run the RX and servos! Ill just accept that at least its working now.

[400driver]

Re maiden complete with a SMC 5900 HV pack. Managed 2 flights with the first landing ok but a little fast. I kept the wings out for the entire flight and felt that it was quite a heart racing first flight. My second landing was not as good as I flared the aircraft a bit too early and did not maintain a steady rate of descent to touchdown, it flattened out too much and I ended up dropping a wing from about 1ft. No real damage , just the pinion to the gear which sheared off. Lucky just 3.99 on Motion so have ordered a few as spares.

I have seen that many people are using lighter packs so have ordered a few of the CHNL HV packs with 4500 MaH, this drops the weight by about 160 gramms. Fingers crossed for the next flight. I think I will use this airframe until I get a bit more confidence before breaking out the replacement.