using UnityEngine;
using System;

public class JetPack : MonoBehaviour {

    private JetPackPath path;
    private double speed = 1, height = 5;
    private bool jetPackOn;

    private void FixedUpdate() {
        MoveWithJetPack();
    }

    private void Update() {
        GetJetPackOn();
    }

    private void MoveWithJetPack() {
        if (jetPackOn) {
            transform.position = path.GetPosition();
            if(path.IsFinished()) {
                transform.position = path.GetEndPosition();
                jetPackOn = false;
            }
        }
    }

    private void GetJetPackOn() {
        if(!jetPackOn && Input.GetMouseButtonDown(0)) {
            InitializeJetPackSequence();
        }
    }

    private void InitializeJetPackSequence() {
        Vector3 startPosition = transform.position;
        Vector3 endPosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
        path = new JetPackPath(startPosition, endPosition, speed, height);
        jetPackOn = true;
    }
}

public class JetPackPath {
    private Vector3 startPosition, endPosition, distance;
    private double height, width;
    private double position, speed;

    public JetPackPath(Vector3 startPosition, Vector3 endPosition, double speed, double height) {
        this.startPosition = startPosition;
        this.endPosition = endPosition;
        this.speed = speed;
        this.height = height;
        distance = endPosition - startPosition;
        width = .5;
    }

    public Vector3 GetPosition() {
        position += speed * Time.fixedDeltaTime;
 
        return startPosition + new Vector3((float)GetXPosition(), (float)GetYPosition(), (float)GetZPosition());
    }

    public Vector3 GetEndPosition() {
        return endPosition;
    }

    public bool IsFinished() {
        return position >= 1.0;
    }

    private double GetXPosition() {
        return position * distance.x;
    }

    private double GetYPosition() {
        double yOffset = distance.y * position;
        double yPosition = GetSquareRoot();
        if (double.IsNaN(yPosition)) yPosition = 0;
        return yPosition + yOffset;
    }

    private double GetZPosition() {
        return position * distance.z;
    }

    private double GetSquareRoot() {
        double fraction = Squared(position - width) / Squared(width);
        double toBeSquareRooted = (1 - fraction) * Squared(height);
        return Math.Sqrt(toBeSquareRooted);
    }

    private double Squared(double value) {
        return Math.Pow(value, 2);
    }
}

Edit: I modified it to support slowing down near the end. It uses new decayStart and decayAmount variables. Both of these variable should be between 0 and 1. If you ever want it to slow down near the beginning as well you could do something similiar to this.

using UnityEngine;
using System;

public class Jetpack : MonoBehaviour {

    private JetPackPath path;
    private double speed = 1, height = 5, decayStart = .75, decayAmount = .25;
    private bool jetPackOn;

    private void FixedUpdate() {
        MoveWithJetPack();
    }

    private void Update() {
        GetJetPackOn();
    }

    private void MoveWithJetPack() {
        if (jetPackOn) {
            transform.position = path.GetPosition();
            if(path.IsFinished()) {
                transform.position = path.GetEndPosition();
                jetPackOn = false;
            }
        }
    }

    private void GetJetPackOn() {
        if(!jetPackOn && Input.GetMouseButtonDown(0)) {
            InitializeJetPackSequence();
        }
    }

    private void InitializeJetPackSequence() {
        Vector3 startPosition = transform.position;
        Vector3 endPosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
        path = new JetPackPath(startPosition, endPosition, speed, height, decayStart, decayAmount);
        jetPackOn = true;
    }
}

public class JetPackPath {
    private Vector3 startPosition, endPosition, distance;
    private double height, width;
    private double position, speed;
    private double decayAmount, decayStart, decayWindow;

    public JetPackPath(Vector3 startPosition, Vector3 endPosition, double speed, double height, double decayStart, double decayAmount) {
        this.startPosition = startPosition;
        this.endPosition = endPosition;
        this.speed = speed;
        this.height = height;
        this.decayStart = decayStart;
        this.decayAmount = decayAmount;
        distance = endPosition - startPosition;
        width = .5;
        decayWindow = 1 - decayStart;
    }

    public Vector3 GetPosition() {
        position += GetSpeed() * Time.fixedDeltaTime;
        return startPosition + new Vector3((float)GetXPosition(), (float)GetYPosition(), (float)GetZPosition());
    }

    public double GetSpeed() {
        if(position >= decayStart) {
            double decay = position - decayWindow;
            double proportion = decay / decayWindow;
            return speed - (proportion * speed * decayAmount);
        }
        return speed;
    }

    public Vector3 GetEndPosition() {
        return endPosition;
    }

    public bool IsFinished() {
        return position >= 1.0;
    }

    private double GetXPosition() {
        return position * distance.x;
    }

    private double GetYPosition() {
        double yOffset = distance.y * position;
        double yPosition = GetSquareRoot();
        if (double.IsNaN(yPosition)) yPosition = 0;
        return yPosition + yOffset;
    }

    private double GetZPosition() {
        return position * distance.z;
    }

    private double GetSquareRoot() {
        double fraction = Squared(position - width) / Squared(width);
        double toBeSquareRooted = (1 - fraction) * Squared(height);
        return Math.Sqrt(toBeSquareRooted);
    }

    private double Squared(double value) {
        return Math.Pow(value, 2);
    }
}