Freewing F14 underpowered

Been doing a lot of head scratching over the problems I'm having with my Freewing F14. Have spent time going through everything I can think of to try and increase the thrust from the twin EDF's but have only managed a small improvement. According to the manufacturer it should be producing over 5000 grams of thrust but I can only achieve just over 3000 grams. Before I start spending money on a power upgrade I thought I would ask if anyone had any suggestions. Its fitted with twin 80mm edf's, two Hobbywing 80amp opto esc's, two 6s 5000mah Turnigy Lipo's. Cheers John

What is the c rating of your batteries?

Have you tried flying it?

John - I'm not a ducted fan man but searched " Freewing F14 Tomcat " and came up with a very interesting posting
by " The RC Geek " claims he's the man who flew the prototype.

This used 2 off 6S 30C 5,800 mAh LiPos.

Interesting reading, goes into loads of detail on setting up etc.

Hope this helps.

Colin.

Hi Colin, thanks for your reply. I have spent literally hours on line researching information about this model and have read reviews and watched videos. This chap from RC geeks has some interesting ideas, 5800 mah packs would be heavier than the lipos that I'm using now which I believe would give a longer flight time but not more power. I have toyed with the idea of fitting 4000mah packs which would be lighter and therefore in theory the model would fly without the extra power. Lots good stuff online tho but no real answer to my problem.
Thanks John

As Mike asks... what is the C rating of your current packs?

And I'm asking if you've tried flying it yet because there is no way of knowing whether your method of measuring thrust is comparable to theirs. IOW, you might already have enough thrust and all this tinkering is wasted when you should be out flying it.

Hi David. The 6s lipos have 30 to 40c. Cheers

Hi Mike. I would like nothing more than to get this model up and flying but it struggles to reach take off speed .

Since this is a twin EDF you can either assume that both motors and ESC's are faulty or that both are fine. And since it is unlikely that both will be faulty this would point to the problem being your batteries (or your radio setup). Does your charger tell you the internal resistance of the cells in your battery? Anything over 10mOhm is not good and if it's over 20mOhm you'll really struggle. Linked to this, are you able to measure current and voltage under load - a wattmeter? You might find that the batteries are just not able to supply the power needed.

As for radio setup, I'm sure you have checked, but are you sure that you are getting full throttle?

I'm not sure if I can measure resistance with my charger I will have a look when I get home. I can measure amps and watts under load I will check those later too. I have sett the throttle using the guide for the hobbywing esc I can only assume that it's right. Thanks tho Mike , my first thought was batteries but wanted a second opinion. I will let you know how I get on with it.