diff --git a/src/MNH/aircraft_balloon_evol.f90 b/src/MNH/aircraft_balloon_evol.f90
index 12f4f595d6cf394d7379a31fabbf68d723013dba..825a798d30ddfd740a4a08875f3ffd404621efb6 100644
--- a/src/MNH/aircraft_balloon_evol.f90
+++ b/src/MNH/aircraft_balloon_evol.f90
@@ -1,4 +1,4 @@
-!MNH_LIC Copyright 2000-2019 CNRS, Meteo-France and Universite Paul Sabatier
+!MNH_LIC Copyright 2000-2020 CNRS, Meteo-France and Universite Paul Sabatier
 !MNH_LIC This is part of the Meso-NH software governed by the CeCILL-C licence
 !MNH_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt
 !MNH_LIC for details. version 1.
@@ -128,7 +128,8 @@ END MODULE MODI_AIRCRAFT_BALLOON_EVOL
 !!      October, 2016 (G.DELAUTIER) LIMA
 !!     March,28, 2018 (P. Wautelet) replace TEMPORAL_DIST by DATETIME_DISTANCE
 !!  Philippe Wautelet: 05/2016-04/2018: new data structures and calls for I/O
-!!
+!  P. Wautelet 01/10/2020: bugfix: initialize GSTORE
+!
 !! --------------------------------------------------------------------------
 !       
 !*      0. DECLARATIONS
@@ -345,6 +346,7 @@ ALLOCATE(XSVW_FLUX(SIZE(PSV,1),SIZE(PSV,2),SIZE(PSV,3),SIZE(PSV,4)))
 ILUOUT = TLUOUT%NLU
 !
 ZR = 0.
+GSTORE = .FALSE.
 !
 !*      1.0  initialization of processor test
 !            --------------------------------
diff --git a/src/MNH/ini_aircraft_balloon.f90 b/src/MNH/ini_aircraft_balloon.f90
index 2d5cc4fb336ba31365415304c56fe39c3001fc81..1fc174da5f90cb86cb27f27e730e217a89cd5412 100644
--- a/src/MNH/ini_aircraft_balloon.f90
+++ b/src/MNH/ini_aircraft_balloon.f90
@@ -3,6 +3,10 @@
 !MNH_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt
 !MNH_LIC for details. version 1.
 !-----------------------------------------------------------------
+! Modifications:
+!  P. Wautelet 01/10/2020: bugfix: DEFAULT_FLYER: add missing default values
+!-----------------------------------------------------------------
+
 !      #########################
 MODULE MODI_INI_AIRCRAFT_BALLOON
 !      #########################
@@ -318,15 +322,24 @@ TPFLYER%STEP   = 60.     ! s
 !
 TPFLYER%LAT     = XUNDEF
 TPFLYER%LON     = XUNDEF
+TPFLYER%XLAUNCH = XUNDEF! X coordinate of launch
+TPFLYER%YLAUNCH = XUNDEF! Y coordinate of launch
 TPFLYER%ALT     = XUNDEF
 TPFLYER%WASCENT = 5.     ! m/s
 TPFLYER%RHO     = XUNDEF
 TPFLYER%PRES    = XUNDEF
+TPFLYER%DIAMETER= XUNDEF
+TPFLYER%AERODRAG= XUNDEF
+TPFLYER%INDDRAG = XUNDEF
+TPFLYER%VOLUME  = XUNDEF
+TPFLYER%MASS    = XUNDEF
 !
 TPFLYER%SEG     = 0
 TPFLYER%SEGCURN = 1
 TPFLYER%SEGCURT = 0.
 !
+TPFLYER%ALTDEF   = .FALSE.
+!
 TPFLYER%X_CUR   = XUNDEF
 TPFLYER%Y_CUR   = XUNDEF
 TPFLYER%Z_CUR   = XUNDEF