SSTO won’t take off

[KomradeIvan1778]

I’m trying to build my first SSTO and I am building it off of SSTO’s made by youtubers. I modified it based off of people with similar problems of their planes not getting off the ground and I still don’t know why my SSTO can’t fly... Can anyone help?     
 

 

EDIT: I can’t post a photo of the craft But is is a simple craft with 2 Panthers and a NERV with some liquid fuel fuselages strutted together. I also have some wings with some structural wings and wing connectors with medium landing gear on them behind the COM and on the front I have intakes on the 2 fuselages with panthers and I have some electric banks, a reaction wheel, and a nose cone... I don’t know why the SSTO isn’t flying or why I can’t post a photo.

 

EDIT 2: Link to the craft https://www.dropbox.com/s/219la3jjxunb6li/Photo Feb 02%2C 4 49 47 PM.jpg?dl=0

Edited February 2, 2020 by KomradeIvan1778

[overkill13]

I had a go at building your craft.  Your main gear are too far back from the CoM so the plane cannot rotate and those control surfaces are pretty weak.  I was able to take off, though.  If you let the plane run all the way off the runway it will lift off without much issue.  Move the wheels forward a bit, just behind the CoM and it will rotate off the runway around 100m/s.

I also see no vertical stabilizer, which shouldn't affect your rotation, but could cause stability issues in flight, especially if the Panthers aren't running during landing or at altitude.  I even had a couple of out of control yaw rotations even with the Panthers going.  The NERV is pretty weak and I couldn't get it to space either.  I can't really tell from the pictures, but you would benefit from angling your wings up a couple of degrees too since that will bring your prograde marker inline with the fuselage at higher speeds, reducing drag.

F1 to take screenshots.

Edited February 2, 2020 by overkill13

[Fierce Wolf]

Possible solutions without changing the concept too much:

1) Tilt the wings to change the angle of attack, so if wind comes this way --------> the wing angle is like this \

(just some degrees, not 45º like the \ bar)

2) Place the rear wheels just below the center of lift, so it can pivot upwards.

3) Make the top wheel taller than the rear ones.

4) The most kerbal solution, put some rockets pointing downwards near the cockpit.