diff --git a/SAS/TMSS/backend/src/tmss/tmssapp/schemas/common_schema_template-stations-1.json b/SAS/TMSS/backend/src/tmss/tmssapp/schemas/common_schema_template-stations-1.json
index 3a634e6cb3fea45cdff17e72df895915bc5a7ceb..3c1082edf043da61227463b693b997f3b8ce2761 100644
--- a/SAS/TMSS/backend/src/tmss/tmssapp/schemas/common_schema_template-stations-1.json
+++ b/SAS/TMSS/backend/src/tmss/tmssapp/schemas/common_schema_template-stations-1.json
@@ -345,7 +345,8 @@
       "title": "SAPs",
       "description": "Station beams",
       "additionalItems": false,
-      "default": [],
+      "default": [{}],
+      "minItems": 1,
       "items": {
         "title": "SAP",
         "headerTemplate": "{{ i0 }} - {{ self.name }}",
diff --git a/SAS/TMSS/backend/src/tmss/tmssapp/schemas/task_template-beamforming_observation-1.json b/SAS/TMSS/backend/src/tmss/tmssapp/schemas/task_template-beamforming_observation-1.json
index ec3c02c3df1b181fe3b22c753a434215f11df119..ca6183d9b0bc64484007c7372866492e5415f657 100644
--- a/SAS/TMSS/backend/src/tmss/tmssapp/schemas/task_template-beamforming_observation-1.json
+++ b/SAS/TMSS/backend/src/tmss/tmssapp/schemas/task_template-beamforming_observation-1.json
@@ -60,7 +60,8 @@
       "$ref": "http://tmss.lofar.org/api/schemas/commonschematemplate/pointing/1/#/definitions/pointing"
     },
     "SAPs": {
-      "$ref": "http://tmss.lofar.org/api/schemas/commonschematemplate/stations/1/#/definitions/SAPs"
+      "$ref": "http://tmss.lofar.org/api/schemas/commonschematemplate/stations/1/#/definitions/SAPs",
+      "default": [{}]
     },
     "duration": {
       "$id": "#duration",