diff --git a/Systems/libraries.xml b/Systems/libraries.xml
index 451c58fa..fd3fdfad 100644
--- a/Systems/libraries.xml
+++ b/Systems/libraries.xml
@@ -68,38 +68,18 @@
 	
 	<filter>
 		<name>FF 1</name>
-		<type>gain</type>
-		<gain>1.0</gain>
-		<update-interval-secs type="double">0.05</update-interval-secs>
-		<input>
-			<expression>
-				<table>
-					<property>/engines/engine[0]/fuel-flow_pph</property> 
-					<entry><ind>   0</ind><dep>   0</dep></entry>
-					<entry><ind>2000</ind><dep>1387</dep></entry>
-					<entry><ind>9000</ind><dep>9847</dep></entry>
-				</table>
-			</expression>
-		</input>
+		<type>exponential</type>
+		<input>/engines/engine[0]/fuel-flow_pph</input>
 		<output>/engines/engine[0]/fuel-flow_actual</output>
+		<filter-time>0.32</filter-time>
 	</filter>
 	
 	<filter>
 		<name>FF 2</name>
-		<type>gain</type>
-		<gain>1.0</gain>
-		<update-interval-secs type="double">0.05</update-interval-secs>
-		<input>
-			<expression>
-				<table>
-					<property>/engines/engine[1]/fuel-flow_pph</property> 
-					<entry><ind>   0</ind><dep>   0</dep></entry>
-					<entry><ind>2000</ind><dep>1387</dep></entry>
-					<entry><ind>9000</ind><dep>9847</dep></entry>
-				</table>
-			</expression>
-		</input>
+		<type>exponential</type>
+		<input>/engines/engine[1]/fuel-flow_pph</input>
 		<output>/engines/engine[1]/fuel-flow_actual</output>
+		<filter-time>0.32</filter-time>
 	</filter>
 	
 	<filter>
diff --git a/revision.txt b/revision.txt
index 3c596919..4c225296 100644
--- a/revision.txt
+++ b/revision.txt
@@ -1 +1 @@
-4716
\ No newline at end of file
+4717
\ No newline at end of file