From 8f0e7e0693405d30d05d1ab67d7ae855f1a561ec Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Wed, 29 Jul 2015 08:20:23 +1000
Subject: [PATCH] Plane: fixed above_location_current() for non-terrain alt

thanks to Lekston for finding the bug (PR#2610)
---
 ArduPlane/altitude.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ArduPlane/altitude.cpp b/ArduPlane/altitude.cpp
index 66ab26a1a3..5fdc398c39 100644
--- a/ArduPlane/altitude.cpp
+++ b/ArduPlane/altitude.cpp
@@ -398,8 +398,8 @@ bool Plane::above_location_current(const Location &loc)
 #endif
 
     float loc_alt_cm = loc.alt;
-    if (!loc.flags.relative_alt) {
-        loc_alt_cm -= home.alt;
+    if (loc.flags.relative_alt) {
+        loc_alt_cm += home.alt;
     }
     return current_loc.alt > loc_alt_cm;
 }