Space movement script

using UnityEngine;
using System.Collections;

public class playerControl : MonoBehaviour
{
    public float rotationSpeed;

    public float maxForwardAcceleration;
    public float maxBackwardAcceleration;
    public float maxStrafeAcceleration;
    public float maxClimbAcceleration;
    public float maxBoostAcceleration;

    public float forwardAcceleration;
    public float boostAcceleration;
    public float backwardAcceleration;
    public float strafeAcceleration;
    public float climbAcceleration;

    private float boost;
    public float forward;
    private float backward;
    private float left;
    private float right;
    private float up;
    private float down;

    void FixedUpdate()
    {
        float pitch = Input.GetAxis("Pitch") * rotationSpeed * Time.fixedDeltaTime;
        float yaw = Input.GetAxis("Yaw") * rotationSpeed * Time.fixedDeltaTime;
        float roll = Input.GetAxisRaw("Roll") * rotationSpeed * Time.fixedDeltaTime;

        //Move forward if under speed limit
        if (forward < maxForwardAcceleration)
        {
            forward += Input.GetAxisRaw("Forward") * forwardAcceleration * Time.fixedDeltaTime;
        }

        //Move backward if under speed limit
        if (backward < maxBackwardAcceleration)
        {
            backward += Input.GetAxisRaw("Backward") * backwardAcceleration * Time.fixedDeltaTime;
        }

        //Move left if under speed limit
        if (left < maxStrafeAcceleration)
        {
            left += Input.GetAxisRaw("Left") * strafeAcceleration * Time.fixedDeltaTime;
        }

        //Move right if under speed limit
        if (right < maxStrafeAcceleration)
        {
            right += Input.GetAxisRaw("Right") * strafeAcceleration * Time.fixedDeltaTime;
        }

        //Move up if under speed limit
        if (up < maxStrafeAcceleration)
        {
            up += Input.GetAxisRaw("Up") * climbAcceleration * Time.fixedDeltaTime;
        }

        //Move down if under speed limit
        if (down < maxStrafeAcceleration)
        {
            down += Input.GetAxisRaw("Down") * climbAcceleration * Time.fixedDeltaTime;
        }

        //Boost
        if (boost < maxBoostAcceleration && Input.GetAxisRaw("Forward") > 0)
        {
            boost += Input.GetAxisRaw("Boost") * boostAcceleration * Time.fixedDeltaTime;
        }

        //Slows if forward key is released
        if (Input.GetAxisRaw("Forward") < 1 && forward > 0)
        {
            forward = 0;
        }

        //Slows if backward key is released
        if (Input.GetAxisRaw("Backward") < 1 && backward > 0)
        {
            backward = 0;
        }

        //Slows if left key is released
        if (Input.GetAxisRaw("Left") < 1 && left > 0)
        {
            left = 0;
        }

        //Slows if right key is released
        if (Input.GetAxisRaw("Right") < 1 && right > 0)
        {
            right = 0;
        }

        //Slows if up key is released
        if (Input.GetAxisRaw("Up") < 1 && up > 0)
        {
            up = 0;
        }

        //Slows if down key is released
        if (Input.GetAxisRaw("Down") < 1 && down > 0)
        {
            down = 0;
        }

        //Slows if boost key is released
        if (Input.GetAxisRaw("Boost") < 1 && boost > 0)
        {
            boost = 0;
        }

        rigidbody.AddRelativeTorque(pitch, yaw, roll);

        rigidbody.AddRelativeForce(Vector3.forward * forward);
        rigidbody.AddRelativeForce(Vector3.back * backward);
        rigidbody.AddRelativeForce(Vector3.left * left);
        rigidbody.AddRelativeForce(Vector3.right * right);
        rigidbody.AddRelativeForce(Vector3.up * up);
        rigidbody.AddRelativeForce(Vector3.down * down);
        rigidbody.AddRelativeForce(Vector3.forward * boost);
    }