--- name: RocketPropulsion last_updated: 2026-06-10T23:09:12Z inherits: - BodyMover - Instance - Object type: class memory_category: Instances tags: - Deprecated summary: "Applies a force so that an assembly follows and faces a target part." --- # Class: RocketPropulsion > Applies a force so that an assembly follows and faces a target part. ## Description The `RocketPropulsion` object applies force on an assembly so that it both **follows** and **faces** a target. It acts like a hybrid of [BodyPosition](/docs/reference/engine/classes/BodyPosition.md) and [BodyGyro](/docs/reference/engine/classes/BodyGyro.md). Unlike other [BodyMovers](/docs/reference/engine/classes/BodyMover.md), `RocketPropulsion` must be instructed to begin applying or stopping force via [Fire()](/docs/reference/engine/classes/RocketPropulsion.md) or [Abort()](/docs/reference/engine/classes/RocketPropulsion.md) respectively. You can detect when the assembly reaches its target using the [ReachedTarget](/docs/reference/engine/classes/RocketPropulsion.md) event which fires once the assembly is within the [TargetRadius](/docs/reference/engine/classes/RocketPropulsion.md) of the [Target](/docs/reference/engine/classes/RocketPropulsion.md) part. ## Properties ### Property: RocketPropulsion.CartoonFactor ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Goals", "capabilities": [ "Physics" ] } ``` This property determines the tendency of the assembly to face the [Target](/docs/reference/engine/classes/RocketPropulsion.md). By default, this property is set to `0.7`. If set to `0`, the assembly will make no effort to face the target. ### Property: RocketPropulsion.MaxSpeed ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Thrust", "capabilities": [ "Physics" ] } ``` This property determines the upper limit of the velocity at which the assembly will move toward the [Target](/docs/reference/engine/classes/RocketPropulsion.md). ### Property: RocketPropulsion.MaxThrust ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Thrust", "capabilities": [ "Physics" ] } ``` This property determines the upper limit of the thrust that may be exerted to move the assembly. Assemblies that have high mass will require more thrust in order to remain airborne and thus track the [Target](/docs/reference/engine/classes/RocketPropulsion.md). ### Property: RocketPropulsion.MaxTorque ```json { "type": "Vector3", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Turn", "capabilities": [ "Physics" ] } ``` This property determines the upper limit on the amount of torque that may be exerted in order to rotate the assembly towards the [Target](/docs/reference/engine/classes/RocketPropulsion.md). It functions similarly to [BodyGyro.MaxTorque](/docs/reference/engine/classes/BodyGyro.md). ### Property: RocketPropulsion.Target ```json { "type": "BasePart", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Goals", "capabilities": [ "Physics" ] } ``` This property determines the object towards which the `RocketPropulsion` will exert force/torque. If set to `nil`, the [TargetOffset](/docs/reference/engine/classes/RocketPropulsion.md) will be used instead. ### Property: RocketPropulsion.TargetOffset ```json { "type": "Vector3", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Goals", "capabilities": [ "Physics" ] } ``` This property determines the world offset from the [Target](/docs/reference/engine/classes/RocketPropulsion.md). It is especially useful when [Target](/docs/reference/engine/classes/RocketPropulsion.md) is set to `nil`, since this property then acts as the target position. ### Property: RocketPropulsion.TargetRadius ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Goals", "capabilities": [ "Physics" ] } ``` This property determines the maximum distance from the [Target](/docs/reference/engine/classes/RocketPropulsion.md) at which the assembly must be in order for [ReachedTarget](/docs/reference/engine/classes/RocketPropulsion.md) to be fired. It does not affect the exerted forces in any way. ### Property: RocketPropulsion.ThrustD ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Thrust", "capabilities": [ "Physics" ] } ``` This property is used to dampen the velocity of the assembly in order to prevent it from overshooting the [Target](/docs/reference/engine/classes/RocketPropulsion.md) and causing a "rubber‑banding" effect. It behaves similarly to [BodyPosition.D](/docs/reference/engine/classes/BodyPosition.md). ### Property: RocketPropulsion.ThrustP ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Thrust", "capabilities": [ "Physics" ] } ``` This property determines how much power is used while applying force in order to reach the [Target](/docs/reference/engine/classes/RocketPropulsion.md) position. The higher this value, the more power will be used and the faster it will be used. This property works similarly to [BodyPosition.P](/docs/reference/engine/classes/BodyPosition.md). ### Property: RocketPropulsion.TurnD ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Turn", "capabilities": [ "Physics" ] } ``` This property specifies how much dampening will be applied to the torque used to face the [Target](/docs/reference/engine/classes/RocketPropulsion.md). When the assembly approaches the goal orientation, it needs to decelerate, otherwise it will rotate past the goal and have to stop and re-accelerate back toward the goal. This often creates an undesirable "rubber‑banding" effect, avoided by applying dampening. The higher this value is set, the greater the dampening curve becomes, or the slower the part will approach the goal orientation. ### Property: RocketPropulsion.TurnP ```json { "type": "float", "access": "ReadWrite", "security": { "read": "None", "write": "None" }, "serialization": { "can_load": true, "can_save": true }, "thread_safety": "ReadSafe", "category": "Turn", "capabilities": [ "Physics" ] } ``` This property determines how much power is used while applying torque in order to face the [Target](/docs/reference/engine/classes/RocketPropulsion.md). The higher this value, the more power will be used and the faster it will be used. ## Methods ### Method: RocketPropulsion:Abort **Signature:** `RocketPropulsion:Abort(): ()` Causes the assembly to stop moving toward its [Target](/docs/reference/engine/classes/RocketPropulsion.md). *Security: None · Thread Safety: Unsafe · Capabilities: Physics* **Returns:** `()` ### Method: RocketPropulsion:Fire **Signature:** `RocketPropulsion:Fire(): ()` Causes the assembly to start moving toward its [Target](/docs/reference/engine/classes/RocketPropulsion.md). *Security: None · Thread Safety: Unsafe · Capabilities: Physics* **Returns:** `()` ### Method: RocketPropulsion:fire **Signature:** `RocketPropulsion:fire(): ()` > **Deprecated:** This function is a deprecated variant of [RocketPropulsion:Fire()](/docs/reference/engine/classes/RocketPropulsion.md) which should be used instead. *Security: None · Thread Safety: Unsafe · Capabilities: Physics* **Returns:** `()` ## Events ### Event: RocketPropulsion.ReachedTarget **Signature:** `RocketPropulsion.ReachedTarget()` Fires when the assembly comes within [TargetRadius](/docs/reference/engine/classes/RocketPropulsion.md) of the [Target](/docs/reference/engine/classes/RocketPropulsion.md). *Security: None · Capabilities: Physics* ## Inherited Members ### From [Instance](/docs/reference/engine/classes/Instance.md) - **Property `Archivable`** (`boolean`): Determines if an Instance and its descendants can be cloned using - **Property `archivable`** (`boolean`): *(deprecated, hidden)* - **Property `Capabilities`** (`SecurityCapabilities`): The set of capabilities allowed to be used for scripts inside this - **Property `Name`** (`string`): A non-unique identifier of the Instance. - **Property `Parent`** (`Instance`): Determines the hierarchical parent of the Instance. - **Property `PredictionMode`** (`PredictionMode`): - **Property `RobloxLocked`** (`boolean`): A deprecated property that used to protect CoreGui objects. *(hidden)* - **Property `Sandboxed`** (`boolean`): When enabled, the instance can only access abilities in its `Capabilities` - **Property `UniqueId`** (`UniqueId`): A unique identifier for the instance. - **Method `AddTag(tag: string): ()`**: Applies a tag to the instance. - **Method `children(): Instances`**: Returns an array of the object's children. *(deprecated)* - **Method `ClearAllChildren(): ()`**: This method destroys all of an instance's children. - **Method `Clone(): Instance`**: Create a copy of an instance and all its descendants, ignoring instances - **Method `clone(): Instance`**: *(deprecated)* - **Method `Destroy(): ()`**: Sets the Instance.Parent property to `nil`, locks the - **Method `destroy(): ()`**: *(deprecated)* - **Method `FindFirstAncestor(name: string): Instance?`**: Returns the first ancestor of the Instance whose - **Method `FindFirstAncestorOfClass(className: string): Instance?`**: Returns the first ancestor of the Instance whose - **Method `FindFirstAncestorWhichIsA(className: string): Instance?`**: Returns the first ancestor of the Instance for whom - **Method `FindFirstChild(name: string, recursive?: boolean): Instance?`**: Returns the first child of the Instance found with the given name. - **Method `findFirstChild(name: string, recursive?: boolean): Instance`**: *(deprecated)* - **Method `FindFirstChildOfClass(className: string): Instance?`**: Returns the first child of the Instance whose - **Method `FindFirstChildWhichIsA(className: string, recursive?: boolean): Instance?`**: Returns the first child of the Instance for whom - **Method `FindFirstDescendant(name: string): Instance?`**: Returns the first descendant found with the given Instance.Name. - **Method `GetActor(): Actor?`**: Returns the Actor associated with the Instance, if any. - **Method `GetAttribute(attribute: string): Variant`**: Returns the value which has been assigned to the given attribute name. - **Method `GetAttributeChangedSignal(attribute: string): RBXScriptSignal`**: Returns an event that fires when the given attribute changes. - **Method `GetAttributes(): Dictionary`**: Returns a dictionary of the instance's attributes. - **Method `GetChildren(): Instances`**: Returns an array containing all of the instance's children. - **Method `getChildren(): Instances`**: *(deprecated)* - **Method `GetDebugId(scopeLength?: int): string`**: Returns a coded string of the debug ID used internally by Roblox. - **Method `GetDescendants(): Instances`**: Returns an array containing all of the descendants of the instance. - **Method `GetFullName(): string`**: Returns a string describing the instance's ancestry. - **Method `GetStyled(name: string, selector: string?): Variant`**: Returns the styled or explicitly modified value of the specified property, - **Method `GetStyledPropertyChangedSignal(property: string): RBXScriptSignal`**: - **Method `GetTags(): Array`**: Gets an array of all tags applied to the instance. - **Method `HasTag(tag: string): boolean`**: Check whether the instance has a given tag. - **Method `IsAncestorOf(descendant: Instance): boolean`**: Returns true if an Instance is an ancestor of the given - **Method `IsDescendantOf(ancestor: Instance): boolean`**: Returns `true` if an Instance is a descendant of the given - **Method `isDescendantOf(ancestor: Instance): boolean`**: *(deprecated)* - **Method `IsPropertyModified(property: string): boolean`**: Returns `true` if the value stored in the specified property is not equal - **Method `QueryDescendants(selector: string): Instances`**: - **Method `Remove(): ()`**: Sets the object's `Parent` to `nil`, and does the same for all its *(deprecated)* - **Method `remove(): ()`**: *(deprecated)* - **Method `RemoveTag(tag: string): ()`**: Removes a tag from the instance. - **Method `ResetPropertyToDefault(property: string): ()`**: Resets a property to its default value. - **Method `SetAttribute(attribute: string, value: Variant): ()`**: Sets the attribute with the given name to the given value. - **Method `WaitForChild(childName: string, timeOut: double): Instance`**: Returns the child of the Instance with the given name. If the - **Event `AncestryChanged`**: Fires when the Instance.Parent property of this object or one of - **Event `AttributeChanged`**: Fires whenever an attribute is changed on the Instance. - **Event `ChildAdded`**: Fires after an object is parented to this Instance. - **Event `childAdded`**: *(deprecated)* - **Event `ChildRemoved`**: Fires after a child is removed from this Instance. - **Event `DescendantAdded`**: Fires after a descendant is added to the Instance. - **Event `DescendantRemoving`**: Fires immediately before a descendant of the Instance is removed. - **Event `Destroying`**: Fires immediately before (or is deferred until after) the instance is - **Event `StyledPropertiesChanged`**: Fires whenever any style property is changed on the instance, including ### From [Object](/docs/reference/engine/classes/Object.md) - **Property `ClassName`** (`string`): A read-only string representing the class this Object belongs to. - **Property `className`** (`string`): *(deprecated)* - **Method `GetPropertyChangedSignal(property: string): RBXScriptSignal`**: Get an event that fires when a given property of the object changes. - **Method `IsA(className: string): boolean`**: Returns true if an object's class matches or inherits from a given class. - **Method `isA(className: string): boolean`**: *(deprecated)* - **Event `Changed`**: Fires immediately after a property of the object changes, with some