diff --git a/Models/Instruments/MCDU/MCDU1.xml b/Models/Instruments/MCDU/MCDU1.xml
index 2133e61a..54116e98 100644
--- a/Models/Instruments/MCDU/MCDU1.xml
+++ b/Models/Instruments/MCDU/MCDU1.xml
@@ -1678,7 +1678,7 @@
 		<object-name>overfly</object-name>
 		<action>
 			<button>0</button>
-			<repeatable>true</repeatable>
+			<repeatable>false</repeatable>
 			<binding>
 				<command>nasal</command>
 				<script>mcdu.button("OVFY", 0);</script>
@@ -1703,11 +1703,23 @@
 		<action>
 			<button>0</button>
 			<repeatable>true</repeatable>
+			<binding>
+				<command>property-adjust</command>
+				<property>/MCDU[0]/clrbtn-timeout</property>
+				<step>1</step>
+				<min>0</min>
+				<max>6</max>
+				<wrap>false</wrap>
+			</binding>
 			<binding>
 				<command>nasal</command>
-				<script>mcdu.button("CLR", 0, "down");</script>
+				<script>mcdu.button("LONGCLR", 0);</script>
 				<condition>
 					<and>
+						<equals>
+							<property>/MCDU[0]/clrbtn-timeout</property>
+							<value>5</value>
+						</equals>
 						<greater-than-equals>
 							<property>systems/electrical/bus/ac-1</property>
 							<value>110</value>
@@ -1718,17 +1730,21 @@
 						</greater-than>
 					</and>
 				</condition>
-			</binding>
+			</binding>					
 			<mod-up>
 				<binding>
 					<command>nasal</command>
-					<script>mcdu.button("CLR", 0, "up");</script>
+					<script>mcdu.button("CLR", 0);</script>
 					<condition>
 						<and>
+							<less-than>
+								<property>/MCDU[0]/clrbtn-timeout</property>
+								<value>5</value>
+							</less-than>
 							<greater-than-equals>
 								<property>systems/electrical/bus/ac-1</property>
 								<value>110</value>
-							</greater-than-equals>
+							</greater-than-equals>						
 							<greater-than>
 								<property>controls/lighting/DU/mcdu1</property>
 								<value>0.01</value>
@@ -1736,6 +1752,11 @@
 						</and>
 					</condition>
 				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/MCDU[0]/clrbtn-timeout</property>
+					<value>0</value>
+				</binding>
 			</mod-up>
 		</action>
 	</animation>
diff --git a/Models/Instruments/MCDU/MCDU2.xml b/Models/Instruments/MCDU/MCDU2.xml
index d49c0a8d..6da38c5c 100644
--- a/Models/Instruments/MCDU/MCDU2.xml
+++ b/Models/Instruments/MCDU/MCDU2.xml
@@ -1678,7 +1678,7 @@
 		<object-name>overfly</object-name>
 		<action>
 			<button>0</button>
-			<repeatable>true</repeatable>
+			<repeatable>false</repeatable>
 			<binding>
 				<command>nasal</command>
 				<script>mcdu.button("OVFY", 1);</script>
@@ -1703,32 +1703,48 @@
 		<action>
 			<button>0</button>
 			<repeatable>true</repeatable>
+			<binding>
+				<command>property-adjust</command>
+				<property>/MCDU[1]/clrbtn-timeout</property>
+				<step>1</step>
+				<min>0</min>
+				<max>6</max>
+				<wrap>false</wrap>
+			</binding>
 			<binding>
 				<command>nasal</command>
-				<script>mcdu.button("CLR", 1, "down");</script>
+				<script>mcdu.button("LONGCLR", 1);</script>
 				<condition>
 					<and>
+						<equals>
+							<property>/MCDU[1]/clrbtn-timeout</property>
+							<value>5</value>
+						</equals>
 						<greater-than-equals>
 							<property>systems/electrical/bus/ac-2</property>
 							<value>110</value>
-						</greater-than-equals>
+						</greater-than-equals>					
 						<greater-than>
 							<property>controls/lighting/DU/mcdu2</property>
 							<value>0.01</value>
 						</greater-than>
 					</and>
 				</condition>
-			</binding>
+			</binding>			
 			<mod-up>
 				<binding>
 					<command>nasal</command>
-					<script>mcdu.button("CLR", 1, "up");</script>
+					<script>mcdu.button("CLR", 1);</script>
 					<condition>
 						<and>
+							<less-than>
+								<property>/MCDU[1]/clrbtn-timeout</property>
+								<value>5</value>
+							</less-than>
 							<greater-than-equals>
 								<property>systems/electrical/bus/ac-2</property>
 								<value>110</value>
-							</greater-than-equals>
+							</greater-than-equals>									
 							<greater-than>
 								<property>controls/lighting/DU/mcdu2</property>
 								<value>0.01</value>
@@ -1736,6 +1752,11 @@
 						</and>
 					</condition>
 				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/MCDU[1]/clrbtn-timeout</property>
+					<value>0</value>
+				</binding>
 			</mod-up>
 		</action>
 	</animation>
diff --git a/Nasal/MCDU/MCDU.nas b/Nasal/MCDU/MCDU.nas
index 2ecd3c93..160b8831 100644
--- a/Nasal/MCDU/MCDU.nas
+++ b/Nasal/MCDU/MCDU.nas
@@ -1499,8 +1499,6 @@ var pagebutton = func(btn, i) {
 	}
 }
 
-var buttonCLRDown = [0,0]; # counter for down event
-
 var button = func(btn, i, event = "") {
 	page = pageNode[i].getValue();
 	if (page != "MCDU") {
@@ -1510,41 +1508,32 @@ var button = func(btn, i, event = "") {
 		} else if (btn == "SP") {
 			mcdu_scratchpad.scratchpads[i].addChar(" ");
 		} else if (btn == "CLR") {
-			if (event == "down") {
-				if (size(scratchpad) > 0) {
-					if (buttonCLRDown[i] > 4) {
-						mcdu_scratchpad.scratchpads[i].empty();
-					}
-					buttonCLRDown[i] = buttonCLRDown[i] + 1;
-				}
-			}
-			else if (event == "" or buttonCLRDown[i]<=4) {
-				buttonCLRDown[i] = 0;
-				#var scratchpad = mcdu_scratchpad.scratchpads[i].scratchpad;  <- useless??
-				if (size(scratchpad) == 0) {
-					mcdu_scratchpad.scratchpads[i].addChar("CLR");
-				} else {
-					mcdu_scratchpad.scratchpads[i].clear();
-				}
-			} else {  # up with buttonCLRDown[i]>4
-				buttonCLRDown[i] = 0;
+			if (size(scratchpad) == 0) {
+				mcdu_scratchpad.scratchpads[i].addChar("CLR");
+			} else {
+				mcdu_scratchpad.scratchpads[i].clear();
 			}
 		} else if (btn == "LONGCLR") {
 			mcdu_scratchpad.scratchpads[i].empty();
 		} else if (btn == "DOT") {
 			mcdu_scratchpad.scratchpads[i].addChar(".");
 		} else if (btn == "PLUSMINUS") {
-			if (right(mcdu_scratchpad.scratchpads[i].scratchpad, 1) == "-") {
-				mcdu_scratchpad.scratchpads[i].clear();
-				mcdu_scratchpad.scratchpads[i].addChar("+");
-			} else if (right(mcdu_scratchpad.scratchpads[i].scratchpad, 1) == "+") {
-				mcdu_scratchpad.scratchpads[i].clear();
+			if (size(scratchpad)==0) {
+				mcdu_message(i, "NOT ALLOWED");
+			} else if (isint(scratchpad)==1) {
 				mcdu_scratchpad.scratchpads[i].addChar("-");
 			} else {
-				mcdu_scratchpad.scratchpads[i].addChar("-");
+				var _toggle = right(scratchpad,1);
+				if (find(_toggle,"-+")!=-1) {
+					_toggle = (_toggle == "-") ? "+" : "-";
+					mcdu_scratchpad.scratchpads[i].clear();
+					mcdu_scratchpad.scratchpads[i].addChar(_toggle);
+				} else {
+					mcdu_message(i, "NOT ALLOWED");
+				}
 			}
 		} else if (btn == "OVFY") {
-			if (mcdu_scratchpad.scratchpads[i].scratchpad == "") {
+			if (size(scratchpad)==0) {
 				mcdu_scratchpad.scratchpads[i].addChar("@");
 			} else {
 				mcdu_message(i, "NOT ALLOWED");