Env/flight axial aceleration

CHANGELOG.md

@@ -31,6 +31,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 Attention: The newest changes should be on top -->
 
 ### Added
+
+- ENH: Add axial_acceleration attribute to the Flight class [#876](https://github.com/RocketPy-Team/RocketPy/pull/876)
 - ENH: Rail button bending moments calculation in Flight class [#893](https://github.com/RocketPy-Team/RocketPy/pull/893)
 - ENH: Built-in flight comparison tool (`FlightComparator`) to validate simulations against external data [#888](https://github.com/RocketPy-Team/RocketPy/pull/888)
 - ENH: Add persistent caching for ThrustCurve API [#881](https://github.com/RocketPy-Team/RocketPy/pull/881)

rocketpy/simulation/flight.py

@@ -2583,6 +2583,15 @@ def acceleration(self):
         """Rocket acceleration magnitude as a Function of time."""
         return (self.ax**2 + self.ay**2 + self.az**2) ** 0.5
 
+    @funcify_method("Time (s)", "Axial Acceleration (m/s²)", "spline", "zero")
+    def axial_acceleration(self):
+        """Axial acceleration magnitude as a Function of time."""
+        return (
+            self.ax * self.attitude_vector_x
+            + self.ay * self.attitude_vector_y
+            + self.az * self.attitude_vector_z
+        )
+
     @cached_property
     def max_acceleration_power_on_time(self):
         """Time at which the rocket reaches its maximum acceleration during

tests/unit/simulation/test_flight.py

@@ -413,6 +413,37 @@ def test_max_values(flight_calisto_robust):
     assert pytest.approx(285.94948, rel=rtol) == test.max_speed
 
 
+@pytest.mark.parametrize(
+    "flight_time_attr",
+    ["t_initial", "out_of_rail_time", "apogee_time", "t_final"],
+)
+def test_axial_acceleration(flight_calisto_custom_wind, flight_time_attr):
+    """Tests the axial_acceleration property by manually calculating the
+    dot product of the acceleration vector and the attitude vector at
+    specific time steps.
+
+    Parameters
+    ----------
+    flight_calisto_custom_wind : rocketpy.Flight
+        Flight object to be tested.
+    flight_time_attr : str
+        The name of the attribute of the flight object that contains the time
+        of the point to be tested.
+    """
+    flight = flight_calisto_custom_wind
+    t = getattr(flight, flight_time_attr)
+
+    calculated_axial_acc = flight.axial_acceleration(t)
+
+    expected_axial_acc = (
+        flight.ax(t) * flight.attitude_vector_x(t)
+        + flight.ay(t) * flight.attitude_vector_y(t)
+        + flight.az(t) * flight.attitude_vector_z(t)
+    )
+
+    assert pytest.approx(expected_axial_acc, abs=1e-9) == calculated_axial_acc
+
+
 def test_effective_rail_length(flight_calisto_robust, flight_calisto_nose_to_tail):
     """Tests the effective rail length of the flight simulation. The expected
     values are calculated by hand, and should be valid as long as the rail