From fba2c3d5cc958aa218507a22d2971c40808a18dc Mon Sep 17 00:00:00 2001
From: Petr Ledvina <ledvinap@gmail.com>
Date: Fri, 9 Oct 2015 13:14:58 +0200
Subject: [PATCH] safety check in altitude code

Make sure altitude is in expected range
---
 src/main/flight/altitudehold.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/flight/altitudehold.c b/src/main/flight/altitudehold.c
index bc65b1c7e..2a0162b8b 100644
--- a/src/main/flight/altitudehold.c
+++ b/src/main/flight/altitudehold.c
@@ -270,7 +270,7 @@ void calculateEstimatedAltitude(uint32_t currentTime)
         BaroAlt = sonarAlt;
     } else {
         BaroAlt -= baroAlt_offset;
-        if (sonarAlt > 0) {
+        if (sonarAlt > 0  && sonarAlt <= 300) {
             sonarTransition = (300 - sonarAlt) / 100.0f;
             BaroAlt = sonarAlt * sonarTransition + BaroAlt * (1.0f - sonarTransition);
         }