Character drops from air when using velocity Jump and transform.translate direction after releasing W key

Yet another jump-jet rendition needing to maneuver a character while in the air. The problem I am facing is that while pressing forward on my character and jumping, everything is great up until I release the forward (W) key. At this point it drops like a stone instead of continuing to move forward while drifting back down to the ground.

I am using transform.Translate on the ground and I know this is where the problem is since there is no forces applied to the rigidbody to keep it going forward in the air. But I'm having trouble figuring out the most appropriate/cleanest/elegant way of coding this. I've looked at potentially using CharacterController, but I'd like to handle this outside of controllers if possible.

Here's the snip of relevant code...

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class PlayerControl : MonoBehaviour {
 
     public float MoveSpeed = 20f;
     public float JumpForce = 15f;
 
     Rigidbody rb;
     
     void Start ()
     {
       rb = GetComponent<Rigidbody>();
     }
     
     void Update ()
     {
       // move player around
       float moveVert = Input.GetAxis("Vertical") * MoveSpeed ;
       float moveHorz = Input.GetAxis("Horizontal") * MoveSpeed ;
     
       moveVert *= Time.deltaTime;
       moveHorz *= Time.deltaTime;
 
       transform.Translate (moveHorz, 0, moveVert);
     }
     
     void FixedUpdate () 
     {
       // jump using rigidbody force
       if (Input.GetButtonDown("Jump"))
         rb.velocity += Vector3.up * JumpForce;
     }
 
 }

In completion, the character will be skating, jump-jetting, and also have a short-burst propulsion pack to propel the character toward the direction they are facing.

Any suggestions on best methods to work with the problem I'm facing above?

Thanks for any input and let me know if I missed some details!