Launcher acceleration is higher than the limited acceleration in F.C

I`m using a cubeorange v4.0.9 for my plane. and it whant to takeoff with “Catapult Launching”
To test the performance of the takeoff, I have already done “Hand Launching” takeoff test and it worked properly.
but about “Catapult Launching” I have a problem with accelerometer which is limited to acceleration 4g.
The initial acceleration of my launcher is about 7g and for this I have noticed that even speed calculations have problems due to F.C limiIt
If I set TKOFF_THR_ACC to 0, Again, there may be an error in the speed calculations due to the initial acceleration created by the launcher?

Its the log of my “Catapult Launching” test: