diff --git a/Nasal/MCDU/WINDCLB.nas b/Nasal/MCDU/WINDCLB.nas
index 9e1bed20..c40782c1 100644
--- a/Nasal/MCDU/WINDCLB.nas
+++ b/Nasal/MCDU/WINDCLB.nas
@@ -147,14 +147,21 @@ var windCLBPage = {
 		if (size(me.windList) >= index) {
 			if (size(mcdu_scratchpad.scratchpads[me.computer].scratchpad) == 13) {
 				var winds = split("/", mcdu_scratchpad.scratchpads[me.computer].scratchpad);
-				me.windList[index - 1] = [winds[0], winds[1], winds[2]];
-				mcdu_scratchpad.scratchpads[me.computer].empty();
-				if (index != 5) {
-					append(me.windList, nil);
+				if (size(winds[0]) == 3 and num(winds[0]) != nil and winds[0] >= 0 and winds[0] <= 360 and
+				size(winds[1]) == 3 and num(winds[1]) != nil and winds[1] >= 0 and winds[1] <= 200 and
+				size(winds[2]) == 5 and ((num(winds[2]) != nil and winds[2] >= 1000 and winds[2] <= 39000) or
+				(num(split("FL", winds[2])[1]) != nil and split("FL", winds[2])[1] >= 10 and split("FL", winds[2])[1] <= 390))) {
+					me.windList[index - 1] = [winds[0], winds[1], winds[2]];
+					mcdu_scratchpad.scratchpads[me.computer].empty();
+					if (index != 5) {
+						append(me.windList, nil);
+					}
+					me._setupPageWithData();
+					me.makeTmpy();
+					me.updateTmpy();
+				} else {
+					mcdu_message(me.computer, "NOT ALLOWED");
 				}
-				me._setupPageWithData();
-				me.makeTmpy();
-				me.updateTmpy();
 			} else {
 				mcdu_message(me.computer, "NOT ALLOWED");
 			}