diff --git a/qt_ui/models.py b/qt_ui/models.py
index 0d8bf45a..8c17ff92 100644
--- a/qt_ui/models.py
+++ b/qt_ui/models.py
@@ -125,7 +125,8 @@ class PackageModel(QAbstractListModel):
         count = flight.count
         name = db.unit_type_name(flight.unit_type)
         estimator = TotEstimator(self.package)
-        delay = datetime.timedelta(seconds=estimator.mission_start_time(flight))
+        delay = datetime.timedelta(
+            seconds=int(estimator.mission_start_time(flight).total_seconds()))
         origin = flight.from_cp.name
         return f"[{task}] {count} x {name} from {origin} in {delay}"