diff --git a/html/layers.js b/html/layers.js
index c61627e..29eb676 100644
--- a/html/layers.js
+++ b/html/layers.js
@@ -86,7 +86,7 @@ function createBaseLayers() {
             attributions: 'Powered by <a href="https://www.esri.com">Esri.com</a>' +
             '— Sources: Esri, i-cubed, USDA, USGS, AEX, GeoEye, Getmapping, Aerogrid, IGN, IGP, UPR-EGP, and the GIS User Community',
             attributionsCollapsible: false,
-            maxZoom: 17,
+            maxZoom: 16,
         }),
         name: 'esri_gray',
         title: 'ESRI.com Gray',
diff --git a/html/script.js b/html/script.js
index fa77824..5a0fc27 100644
--- a/html/script.js
+++ b/html/script.js
@@ -2149,6 +2149,10 @@ function initMap() {
             case "t":
                 selectAllPlanes();
                 break;
+            case "g":
+                nogpsOnly = !nogpsOnly;
+                refreshFilter();
+                break;
             case "h":
                 resetMap();
                 break;
@@ -3518,7 +3522,8 @@ function selectAllPlanes() {
     if (globeIndex) {
         for (let i in PlanesOrdered) {
             let plane = PlanesOrdered[i];
-            plane.processTrace();
+            if (plane.visible && plane.inView)
+                plane.processTrace();
         }
     }
     refreshFeatures();