Type 7 Stability analysis is not running

[AadarshGejage]

dear team, when I am trying to run type 7 analysis it is not running showing this error flow5 v7.53
Mon Feb 16 20:37:45 2026

Launching analysis

Initializing task

Plane name
T7-TriUniform-ThickSurf-Inviscid

Checking plane and polar data
...done

T7-TriUniform-ThickSurf-Inviscid
Type 7 - Stability polar

ρ = 1.225 kg/m³
ν = 1.5e-05 m²/s

RFF = 10
Core radius = 0.001 mm

Running in multi-threaded mode

Linear system calculations in floating point double precision

Using S. Nintcheu-Fata's method for off-plane integrals

Initializing the triangle analysis
Checking element sizes
...done

Connecting triangular panels... done
Time to make the triangle connections: 4.245 s

Setting flap positions

Counted 24782 elements
Matrix size = 24782

Allocating result arrays

Solving the problem...

Making the unit RHS vectors... done in 1.493 s
Making the influence matrix... done in 1.309 s
Adding the wake's contribution... done in 1.466 s
LAPACK - LU factorization... done in 20.639 s
Back-substituting RHS... done in 1.619 s
Making unit panel velocities... done
Computing trimmed conditions
Unsuccessful attempt to trim the model for control position=0.00 - skipping.

Panel analysis completed ... Errors encountered

Cleaning up
Analysis ended Mon Feb 16 20:38:17 2026
Elapsed: 32.02 s kindly help

[Flying-Geek]

Your model could not be trimmed, so make sure that the model is stable and creates a positive lift at Cm = 0.

[Flying-Geek]

Your plane may be stable, but it is unbalanced.
I would highly recommend you read up on aeroplane stability before you try to proceed with the stability analysis. Without a good understanding of the topic any results the analysis produces are going to be difficult to interpret and meaningless.

Stefan

[AadarshGejage]

Hi, Stefan, thank you for reply, my aircraft is having flight controller so that it will add elevator deflection during flight results in my AOA will get more, and I will get a level flight as with gyroscope present in flight controller will help me to maintain my level stable flight, so I will lose my efficiency naturally as I need continues elevator deflection, so can you please suggest which things can help me to get my cm=0 making positive lift, 1) increasing tail volume will help me? Or any other solution will help me out? eagerly waiting for the reply

[AadarshGejage]

@techwinder waiting for your comment as well, thank you

[Flying-Geek]

Increasing the tail volume will not help.
I can describe to you step by step how to get the analysis to run, but this is not the issue here.
The result you get from a stability analysis let you judge the aeroplanes dynamic behaviour, which requires an understanding of said dynamics, and before and more importantly that of the underlying concepts of static stability and balance.
Without that the results of the analysis will mean nothing to you or anybody else because they're not build on a solid foundation.

I cannot break down an entire set of flight mechanics lectures into a small post here, so the only thing I can do is to recommend you to have a look at literature yourself.
If you just want this plane to fly, I recommend abandoning the idea of a stability analysis and using statistical rule-of-thumb methods and testing it with a smaller free flight model instead.
My response here may seem harsh, but without the proper understanding any analysis results are more likely to lead you in the wrong direction than to be useful to you.

Stefan

[AadarshGejage]

Hey Stefen, I appreciate your comment I will go through all documentation required. thank you once again