From b5a2bf2c6fe091fc1a8ba26bc85a13fe2b2631a8 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Fri, 14 Oct 2016 08:34:54 +1100
Subject: [PATCH] Plane: only revert a tuning parameter if it has been set

fixes a 2nd transmitter tuning bug found by expntly
---
 ArduPlane/tuning.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ArduPlane/tuning.cpp b/ArduPlane/tuning.cpp
index 33c409634e..b6947d8bf1 100644
--- a/ArduPlane/tuning.cpp
+++ b/ArduPlane/tuning.cpp
@@ -275,7 +275,11 @@ void AP_Tuning_Plane::reload_value(uint8_t parm)
     default:
         AP_Float *f = get_param_pointer(parm);
         if (f != nullptr) {
-            f->load();
+            uint64_t param_bit = (1ULL << parm);
+            // only reload if we have set this parameter at some point
+            if (param_bit & have_set) {
+                f->load();
+            }
         }
         break;
     }