Why is the "Look Under Mask" option no longer available for some 6DOF Equations of Motion blocks in MATLAB R2025a?

Starting in MATLAB R2025a, the “Look Under Mask” option is disabled for certain six-degrees-of-freedom (6DOF) Equation of Motion (EOM) blocks from the Aerospace Blockset, such as the "6DOF (Quaternion)" block. 

In MATLAB R2024b, you can still open the mask and view the internal implementation of these blocks. What's changed?

Answer 1

[MathWorks Support Team]

The 6DOF Body-Axes EOM blocks have been converted to built-in core Simulink blocks in MATLAB R2025a. These blocks are no longer implemented as masked subsystems, so it is not possible to view their internal logic.

The updated blocks are now written in C++, similar to other standard Simulink blocks. This change enables improved performance and better integration with Simulink features.