diff --git a/aman/app.py b/aman/app.py
index 2ec17df..ff120b5 100644
--- a/aman/app.py
+++ b/aman/app.py
@@ -18,7 +18,8 @@ class InboundEncoder(JSONEncoder):
         delimiter = pta.find('.')
         if -1 == delimiter:
             delimiter = pta.find('+')
-        return { 'callsign' : o.Callsign, 'fixed' : o.FixedSequence, 'runway' : o.PlannedRunway.Name, 'pta' : pta[0:delimiter] }
+        delta = int((o.PlannedArrivalTime - o.InitialArrivalTime).total_seconds() / 60.0);
+        return { 'callsign' : o.Callsign, 'fixed' : o.FixedSequence, 'runway' : o.PlannedRunway.Name, 'pta' : pta[0:delimiter], 'delay' : delta }
 
 class RunwaySequencingEncoder(JSONEncoder):
     def default(self, o):