I'm trying to get an enemy plane to explode when hit by a projectile but it doesn't work

I am using an empty game object with a triggered collider at the back of the plane (where I hit)
I am using this script:

using System.Collections;
using UnityEngine;

public class explode: MonoBehaviour {
public GameObject explosion;


void OnTriggerEnter(Collider other)
 {
          if (other.tag == "bullet") 
          {
            
	    Destroy (transform.parent.parent.gameObject);
            Instantiate(explosion, transform.position, transform.rotation);
          } 
          
          
  }
}

I attributed the script to the game object. When I crash my plane into the collider it explodes but when I shoot at it with a bullet it doesn’t. I don’t know if this is because the shot bullets are clones.

Do the bullets have correct colliders?
Do they have the tag?

Also, have you tried doing if (other.gameObject.tag == "bullet")

Also, if your bullet is moving to fast it could be that collisions don’t work correctly.

Maybe transform.parent.parent is wrong. Check this out Unity - Scripting API: Transform.SetParent
It shows that the Destroy changes for the gameobject when false. Possibly inside ( ) your Destroy statement is false?