In order to obtain the flight attitude of terminal-sensitive bullet in stable state scanning phase, and according to the measuring principle of gyroscope-free inertial measurement unit (GF-IMU), a ten accelerometer configuration scheme and attitude calculation algorithm were put forward. With projectile motion model, the designed GF-IMU was simulated and analyzed by MATLAB. The result shows that in 30 seconds, the centroid linear acceleration can be neglected. As time increases, angular velocity increases, and the error increases gradually, but the extent of increase is small. Since the steady-state scanning time of terminal sensitive bullet is only more than ten seconds, the measurement unit can accurately obtain the attitude data of the steady state scanning stage of terminal-sensitive bullet.