diff --git a/modules/deeplearning/icing_fcn.py b/modules/deeplearning/icing_fcn.py
index b5706202072d2d75057917f9e85936d6be20f345..d1d9d3f2303def2f9ec55898f52894e0b9d20309 100644
--- a/modules/deeplearning/icing_fcn.py
+++ b/modules/deeplearning/icing_fcn.py
@@ -1017,7 +1017,13 @@ class IcingIntensityFCN:
         cnn = self.build_cnn()
         print(cnn.shape, self.inputs[1].shape)
         if self.USE_FLIGHT_ALTITUDE:
-            cnn = tf.keras.layers.concatenate([cnn, self.inputs[1]])
+            # cnn = tf.keras.layers.concatenate([cnn, self.inputs[1]])
+            # -- experimental
+            cnn_shape = cnn.shape
+            falt = tf.zeros((cnn_shape[0], cnn_shape[1] // 16, cnn_shape[2] // 16, 5))
+            falt[:, :, :, :] = self.inputs[1][:, 0, 0, :]
+            cnn = tf.keras.layers.concatenate([cnn, falt])
+            # ------------------------------------------------------------
         self.build_fcl(cnn)
         self.model = tf.keras.Model(self.inputs, self.logits)