From 415a2f39c3dcc8dcf9cbb85d685b8feb0ea6a080 Mon Sep 17 00:00:00 2001
From: Ian Renton <ian@ianrenton.com>
Date: Sun, 28 Jul 2024 10:25:00 +0100
Subject: [PATCH] Remove altitude field for ships to get grey icons in skyaware

---
 ais2adsb.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/ais2adsb.py b/ais2adsb.py
index 5a937ef..5bd2f8e 100755
--- a/ais2adsb.py
+++ b/ais2adsb.py
@@ -148,10 +148,11 @@ def sendBaseStation(decoded):
         tstr = now_utc.strftime("%H:%M:%S.%f")[:-3]
         callsign = "V:" + ("00000" + str(decoded['mmsi']) )[-6:]
         ground_flag = 1 if alt < 1 else 0
+        alt_str = "" if alt < 1 else str(alt)
 
         global client_socket
 
-        spos = f'MSG,2,1,0,{ICAO},1,{dstr},{tstr},{dstr},{tstr},,{alt},{speed},{heading},{lat},{lon},,,,,,{ground_flag}\n'
+        spos = f'MSG,2,1,0,{ICAO},1,{dstr},{tstr},{dstr},{tstr},,{alt_str},{speed},{heading},{lat},{lon},,,,,,{ground_flag}\n'
         scs = f'MSG,1,1,0,{ICAO},1,{dstr},{tstr},{dstr},{tstr},{callsign},,,,,,,,,,,\n'
 
         if client_socket == None: