diff --git a/src/MNH/aircraft_balloon_evol.f90 b/src/MNH/aircraft_balloon_evol.f90
index 73d2b129408c2d538b723562c6c9271e6283afc7..f4a3dd5d236e1b1a9a7a0dbd92b1ea59236c365a 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.
@@ -122,6 +122,7 @@ END MODULE MODI_AIRCRAFT_BALLOON_EVOL
 !!     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 13/09/2019: budget: simplify and modernize date/time management
+!  P. Wautelet 01/10/2020: bugfix: initialize GSTORE
 !
 !! --------------------------------------------------------------------------
 !       
@@ -334,6 +335,7 @@ 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 e098bed2d165f00a60275766b01c88dc760111bf..0b22d34031958913fa591c450709ede432d98301 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
 !      #########################
@@ -319,15 +323,24 @@ 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