diff --git a/aviary/variable_info/variable_meta_data.py b/aviary/variable_info/variable_meta_data.py
index 759640328..a9966c6fd 100644
--- a/aviary/variable_info/variable_meta_data.py
+++ b/aviary/variable_info/variable_meta_data.py
@@ -70,7 +70,7 @@
     },
     units='lbm',
     desc='air conditioning system mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -122,7 +122,7 @@
     },
     units='lbm',
     desc='mass of anti-icing system (auxiliary gear)',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -163,7 +163,7 @@
     },
     units='lbm',
     desc='mass of auxiliary power unit',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -204,7 +204,7 @@
     },
     units='lbm',
     desc='avionics mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -493,7 +493,7 @@
     },
     units='lbm',
     desc='mass of canards',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -519,7 +519,7 @@
     },
     units='unitless',
     desc='canard theoretical taper ratio',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -619,7 +619,7 @@
     historical_name={"GASP": 'INGASP.WFC', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total mass of cockpit controls, fixed wing controls, and SAS',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 #   _____                            _____                    _                       _
@@ -646,7 +646,7 @@
     },
     units='lbm',
     desc='mass of passenger baggage',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -679,7 +679,7 @@
     },
     units='lbm',
     desc='mass of cargo containers',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -710,7 +710,7 @@
     },
     units='lbm',
     desc='total mass of cargo',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -719,7 +719,7 @@
     historical_name={"GASP": 'INGASP.CW(12)', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='mass of catering items per passenger',
-    default_value=0.0,  # changed from 0.7
+    default_value=0.0,
 )
 
 #   ___               _
@@ -740,7 +740,7 @@
     desc='number of business class passengers that the aircraft is designed to accommodate',
     types=int,
     option=True,
-    default_value=0,  # AviaryValues.get_val(Aircraft.CrewPayload.NUM_BUSINESS_CLASS),
+    default_value=0,
 )
 
 add_meta_data(
@@ -806,7 +806,7 @@
     },
     units='lbm',
     desc='total mass of the flight crew and their baggage',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -866,7 +866,7 @@
     },
     units='lbm',
     desc='total mass of the non-flight crew and their baggage',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1013,7 +1013,7 @@
     },
     units='lbm',
     desc='TBD: total mass of all passengers without their baggage',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1034,7 +1034,7 @@
     historical_name={"GASP": 'INGASP.WPL', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='mass of passenger payload, including passengers, passenger baggage',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1053,14 +1053,14 @@
     },
     units='lbm',
     desc='mass of passenger service equipment',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
     Aircraft.CrewPayload.PASSENGER_SERVICE_MASS_PER_PASSENGER,
     meta_data=_MetaData,
     historical_name={"GASP": "INGASP.CW(9)", "FLOPS": None, "LEAPS1": None},
-    default_value=0.0,  # changed from 2.0
+    default_value=0.0,
     units="lbm",
     desc='mass of passenger service items mass per passenger',
 )
@@ -1170,7 +1170,7 @@
     historical_name={"GASP": 'INGASP.SKCC', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of cockpit controls',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1248,12 +1248,12 @@
     },
     units='lbm',
     desc='empty mass margin',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
     # Note users must enable this feature, or the associated calculation is
-    # discarded
+    # discarded. Default to 0.0
     Aircraft.Design.EMPTY_MASS_MARGIN_SCALER,
     meta_data=_MetaData,
     historical_name={
@@ -1263,7 +1263,7 @@
     },
     units='unitless',
     desc='empty mass margin scaler',
-    default_value=0.0,  # Note: not 1.0 here
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1276,7 +1276,7 @@
     meta_data=_MetaData,
     units='lbm',
     desc='total mass of all user-defined external subsystems',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1292,7 +1292,7 @@
     },
     units='unitless',
     desc='table of component fineness ratios',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1302,7 +1302,7 @@
     units='lbm',
     desc='total mass of fixed equipment: APU, Instruments, Hydraulics, Electrical, '
     'Avionics, AC, Anti-Icing, Auxilary Equipment, and Furnishings',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1311,7 +1311,7 @@
     historical_name={"GASP": 'INGASP.WFUL', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total mass of fixed useful load: crew, service items, trapped oil, etc',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1369,7 +1369,7 @@
     historical_name={"GASP": 'INGASP.CLALPH', "FLOPS": None, "LEAPS1": None},
     units="1/rad",
     desc='lift curve slope at cruise mach number',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1427,7 +1427,7 @@
     },
     units='lbm',
     desc='operating mass empty of the aircraft',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1507,7 +1507,7 @@
     },
     units='lbm',
     desc='Total structural group mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1558,7 +1558,7 @@
     },
     units='lbm',
     desc='Total systems & equipment group mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1570,7 +1570,7 @@
     historical_name={"GASP": None, "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='Total systems & equipment group mass without additional 1% of ' 'empty mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1595,7 +1595,7 @@
     },
     units='ft**2',
     desc='total aircraft wetted area',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1617,7 +1617,7 @@
     },
     units='lbm',
     desc='design landing mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1678,7 +1678,7 @@
     },
     units='lbm',
     desc='zero fuel mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1720,7 +1720,7 @@
     historical_name={"GASP": 'INGASP.LCABLE', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='length of cable for hybrid electric augmented system',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -1739,7 +1739,7 @@
     },
     units='lbm',
     desc='mass of the electrical system',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2345,8 +2345,8 @@
         "LEAPS1": 'aircraft.inputs.L0_overrides.thrust_reversers_weight',
     },
     units='unitless',
-    desc='scaler for mass of thrust reversers on engines',
-    default_value=0.0,  # FLOPS/LEAPS1 default value
+    desc='scaler for mass of thrust reversers on engines. In FLOPS/LEAPS1 default to 0.0',
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2601,7 +2601,7 @@
     },
     units='lbm',
     desc='mass of vertical fins',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2642,7 +2642,7 @@
     },
     units='unitless',
     desc='vertical fin theoretical taper ratio',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 #  ______                  _
@@ -2663,7 +2663,7 @@
     },
     units='lbm',
     desc='fuel capacity of the auxiliary tank',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2684,7 +2684,7 @@
     },
     units='unitless',
     desc='fuel capacity factor',
-    default_value=1.0,  # changed from 23.0
+    default_value=1.0,
 )
 
 add_meta_data(
@@ -2693,7 +2693,7 @@
     historical_name={"GASP": 'INGASP.FUELD', "FLOPS": None, "LEAPS1": None},
     units='lbm/galUS',
     desc='fuel density',
-    default_value=0.0,  # changed from 6.687
+    default_value=0.0,
 )
 
 # TODO replace with actual fuel density
@@ -2717,10 +2717,10 @@
     Aircraft.Fuel.FUEL_MARGIN,
     meta_data=_MetaData,
     historical_name={"GASP": 'INGASP.FVOL_MRG', "FLOPS": None, "LEAPS1": None},
-    units='unitless',  # percent
-    desc='excess fuel volume required, essentially the amount of fuel above '
+    units='unitless',
+    desc='percentage of excess fuel volume required, essentially the amount of fuel above '
     'the design point that there has to be volume to carry',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2739,7 +2739,7 @@
     },
     units='lbm',
     desc='fuel system mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2748,7 +2748,7 @@
     historical_name={"GASP": 'INGASP.SKFS', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of fuel system',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2779,7 +2779,7 @@
     },
     units='lbm',
     desc='fuel capacity of the fuselage',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2812,7 +2812,7 @@
     desc='Total fuel capacity of the aircraft including wing, fuselage and '
     'auxiliary tanks. Used in generating payload-range diagram (Default = '
     'wing_capacity + fuselage_capacity + aux_capacity)',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2830,7 +2830,7 @@
     },
     units='galUS',  # need to check this
     desc='Total fuel volume',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2849,14 +2849,14 @@
     },
     units='lbm',
     desc='unusable fuel mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
     Aircraft.Fuel.UNUSABLE_FUEL_MASS_COEFFICIENT,
     meta_data=_MetaData,
     historical_name={"GASP": "INGASP.CW(13)", "FLOPS": None, "LEAPS1": None},
-    default_value=0.0,  # 6.0
+    default_value=0.0,
     units="unitless",
     desc='mass trend coefficient of trapped fuel factor',
 )
@@ -2885,7 +2885,7 @@
     },
     units='lbm',
     desc='fuel capacity of the auxiliary tank',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2894,7 +2894,7 @@
     historical_name={"GASP": 'INGASP.SKWF', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='fraction of total theoretical wing volume used for wing fuel',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2969,7 +2969,7 @@
     historical_name={"GASP": 'INGASP.FVOLW_DES', "FLOPS": None, "LEAPS1": None},
     units='ft**3',
     desc='wing tank fuel volume when carrying design fuel plus fuel margin',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2978,7 +2978,7 @@
     historical_name={"GASP": 'INGASP.FVOLW_GEOM', "FLOPS": None, "LEAPS1": None},
     units='ft**3',
     desc='wing tank fuel volume based on geometry',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -2987,7 +2987,7 @@
     historical_name={"GASP": 'INGASP.FVOLW_MAX', "FLOPS": None, "LEAPS1": None},
     units='ft**3',
     desc='wing tank volume based on maximum wing fuel weight',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 
@@ -3018,7 +3018,7 @@
     },
     units='lbm',
     desc='Total furnishings system mass',
-    default_value=0.0,  # changed form None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3027,7 +3027,7 @@
     historical_name={"GASP": None, "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='Base furnishings system mass without additional 1% empty mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3076,7 +3076,7 @@
     },
     units='ft',
     desc='average fuselage diameter',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3239,7 +3239,7 @@
     },
     units='lbm',
     desc='mass of the fuselage structure',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3274,7 +3274,7 @@
     },
     units='ft',
     desc='maximum fuselage height',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3404,7 +3404,7 @@
     },
     units='ft**2',
     desc='fuselage planform area',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3413,7 +3413,7 @@
     historical_name={"GASP": 'INGASP.DELP', "FLOPS": None, "LEAPS1": None},
     units='psi',
     desc='fuselage pressure differential during cruise',
-    default_value=0.0,  # changed from 7.5
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3462,7 +3462,7 @@
     },
     units='ft**2',
     desc='fuselage wetted area',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3499,7 +3499,7 @@
     },
     units='ft**2',
     desc='horizontal tail theoretical area; overridden by vol_coeff, if '
-    'vol_coeff > 0.0',  # this appears to never be calculated in Aviary, need to show users the overriding capability of Aviary
+    'vol_coeff > 0.0',  # TODO: this appears to never be calculated in Aviary, need to show users the overriding capability of Aviary
     default_value=0.0,
 )
 
@@ -3605,7 +3605,7 @@
     },
     units='lbm',
     desc='mass of horizontal tail',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3614,7 +3614,7 @@
     historical_name={"GASP": 'INGASP.SKY', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of horizontal tail',
-    default_value=0.0,  # changed from 0.18
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3636,7 +3636,7 @@
     historical_name={"GASP": 'INGASP.ELTH', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='moment arm of horizontal tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3653,7 +3653,7 @@
     historical_name={"GASP": 'INGASP.CRCLHT', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='horizontal tail root chord',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3662,7 +3662,7 @@
     historical_name={"GASP": 'INGASP.BHT', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='span of horizontal tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3690,7 +3690,7 @@
     },
     units='unitless',
     desc='horizontal tail theoretical taper ratio',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3720,7 +3720,7 @@
     'tail is mounted. Defaults: 0.0 == for body mounted (default for '
     'transport with all engines on wing); 1.0 == for T tail '
     '(default for transport with multiple engines on fuselage)',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3748,7 +3748,7 @@
     },
     units='ft**2',
     desc='horizontal tail wetted area',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3780,7 +3780,7 @@
     historical_name={"GASP": 'INGASP.CW(3)', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='mass trend coefficient of hydraulics for flight control system',
-    default_value=0.0,  # changed from 0.10
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3789,7 +3789,7 @@
     historical_name={"GASP": 'INGASP.CW(4)', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='mass trend coefficient of hydraulics for landing gear',
-    default_value=0.0,  # changed from 0.16
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3808,7 +3808,7 @@
     },
     units='lbm',
     desc='mass of hydraulic system',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3872,7 +3872,7 @@
     historical_name={"GASP": 'INGASP.CW(2)', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='mass trend coefficient of instruments',
-    default_value=0.0,  # changed from 0.0862
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -3964,7 +3964,7 @@
     },
     units='lbm',
     desc='mass of main landing gear (WMG in GASP)',
-    default_value=0,  # added
+    default_value=0,
 )
 
 add_meta_data(
@@ -3973,7 +3973,7 @@
     historical_name={"GASP": 'INGASP.SKMG', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of main gear, fraction of total landing gear',
-    default_value=0.0,  # changed from 0.85
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4012,7 +4012,7 @@
     historical_name={"GASP": 'INGASP.SKLG', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of landing gear',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4027,7 +4027,7 @@
     },
     units='lbm',
     desc='mass of nose landing gear',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4105,7 +4105,7 @@
     },
     units='ft',
     desc='Average diameter of engine nacelles for each engine model',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4120,7 +4120,7 @@
     },
     units='ft',
     desc='Average length of nacelles for each engine model',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4144,7 +4144,7 @@
     historical_name={"GASP": 'INGASP.CLEARqDN', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='the minimum number of nacelle diameters above the ground that the bottom of the nacelle must be',
-    default_value=0.0,  # changed from 0.2
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4317,7 +4317,7 @@
     },
     units='lbm',
     desc='mass of paint for all wetted area',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4372,7 +4372,7 @@
     },
     units='lbm',
     desc='Total propulsion group mass',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 # TODO clash with per-engine scaling, need to resolve w/ heterogeneous engine
@@ -4397,7 +4397,7 @@
     historical_name={"GASP": None, "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total estimated mass of the engine controls for all engines on aircraft',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4406,7 +4406,7 @@
     historical_name={"GASP": 'INGASP.WEP', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total mass of all engines on aircraft',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4425,7 +4425,7 @@
     },
     units='lbm',
     desc='engine oil mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4434,7 +4434,7 @@
     historical_name={"GASP": None, "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total engine pod mass for all engines on aircraft',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4446,7 +4446,7 @@
     units='lbm',
     desc='sum of engine control, starter, and additional mass for all engines '
     'on aircraft',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4518,7 +4518,7 @@
     historical_name={"GASP": None, "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='total mass of thrust reversers for all engines on aircraft',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 #   _____   _                    _
@@ -4690,7 +4690,7 @@
     },
     units='unitless',
     desc='vertical tail theoretical aspect ratio',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4782,7 +4782,7 @@
     },
     units='lbm',
     desc='mass of vertical tail',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4791,7 +4791,7 @@
     historical_name={"GASP": 'INGASP.SKZ', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of the vertical tail',
-    default_value=0.0,  # changed from 0.22
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4813,7 +4813,7 @@
     historical_name={"GASP": 'INGASP.ELTV', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='moment arm of vertical tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4845,7 +4845,7 @@
     historical_name={"GASP": 'INGASP.CRCLVT', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='root chord of vertical tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4854,7 +4854,7 @@
     historical_name={"GASP": 'INGASP.BVT', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='span of vertical tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4870,7 +4870,7 @@
     },
     units='deg',
     desc='quarter-chord sweep of vertical tail',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -4883,7 +4883,7 @@
     },
     units='unitless',
     desc='vertical tail theoretical taper ratio',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5055,7 +5055,7 @@
     },
     units='unitless',
     desc='Reference aspect ratio, used for detailed wing mass estimation.',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5064,7 +5064,7 @@
     historical_name={"GASP": 'INGASP.CBARW', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='mean aerodynamic chord of the wing',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5076,8 +5076,9 @@
         "LEAPS1": 'aircraft.outputs.L0_wing.bending_material_factor',
     },
     units='unitless',
-    desc='Wing bending material factor with sweep adjustment. Used to compute',
-    default_value=0.0,  # added
+    desc='Wing bending material factor with sweep adjustment. Used to compute '
+    'Aircraft.Wing.BENDING_MATERIAL_MASS',
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5092,7 +5093,7 @@
     },
     units='lbm',
     desc='wing mass breakdown term 1',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5120,7 +5121,7 @@
     },
     units='lbm',
     desc='wing mass breakdown term 4',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5142,7 +5143,7 @@
     historical_name={"GASP": 'INGASP.CRCLW', "FLOPS": None, "LEAPS1": None},
     units='ft',
     desc='wing chord at fuselage centerline',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5193,7 +5194,7 @@
     units='unitless',
     desc='chord lengths as fractions of semispan at station locations; '
     'overwrites station_chord_lengths',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5228,7 +5229,7 @@
     },
     units='ft**2',
     desc='area of wing control surfaces',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5243,7 +5244,7 @@
     units='unitless',
     desc='Defines the ratio of total moveable wing control surface areas '
     '(flaps, elevators, spoilers, etc.) to reference wing area.',
-    default_value=0.0,  # changed from 0.333
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5285,7 +5286,7 @@
     units='unitless',
     desc='Engine inertia relief factor for wingspan inboard of engine locations. Used '
     'to compute Aircraft.Wing.BENDING_MATERIAL_MASS',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5309,7 +5310,7 @@
     historical_name={"GASP": 'INGASP.CFOC', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='ratio of flap chord to wing chord',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5421,7 +5422,7 @@
     historical_name={"GASP": 'INGASP.SWFOLD', "FLOPS": None, "LEAPS1": None},
     units='ft**2',
     desc='wing area of folding part of wings',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5495,7 +5496,7 @@
     historical_name={"GASP": 'INGASP.WHLDEV', "FLOPS": None, "LEAPS1": None},
     units='lbm',
     desc='mass of the high lift devices',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5504,7 +5505,7 @@
     historical_name={"GASP": 'INGASP.WCFLAP', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of high lift devices (default depends on flap type)',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5606,7 +5607,7 @@
     desc='Define the sweep of load path at station locations. Typically '
     'parallel to rear spar tending toward max t/c of airfoil. The Ith value '
     'is used between wing stations I and I+1.',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5619,7 +5620,7 @@
     },
     units='lbf/ft**2',
     desc='wing loading',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5649,7 +5650,7 @@
     },
     units='lbm',
     desc='wing total mass',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5658,7 +5659,7 @@
     historical_name={"GASP": 'INGASP.SKWW', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='mass trend coefficient of the wing without high lift devices',
-    default_value=0.0,  # changed from 133.4
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5758,7 +5759,7 @@
     },
     units='lbm',
     desc='wing mass breakdown term 3',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5780,7 +5781,7 @@
     historical_name={"GASP": 'INGASP.HWING', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='wing location on fuselage (0 = low wing, 1 = high wing)',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5851,7 +5852,7 @@
     },
     units='lbm',
     desc='wing mass breakdown term 2',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5873,7 +5874,7 @@
     historical_name={"GASP": 'INGASP.CLEOC', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='ratio of slat chord to wing chord',
-    default_value=0.0,  # changed from 0.15
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5890,7 +5891,7 @@
     historical_name={"GASP": 'INGASP.BLEOB', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='fraction of wing leading edge with slats',
-    default_value=0.0,  # changed from 0.9
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5978,7 +5979,7 @@
     },
     units='lbm',
     desc='mass of surface controls',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -5987,7 +5988,7 @@
     historical_name={"GASP": 'INGASP.SKFW', "FLOPS": None, "LEAPS1": None},
     units="unitless",
     desc='Surface controls weight coefficient',
-    default_value=0.0,  # changed from 0.404
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6090,7 +6091,7 @@
     },
     units='unitless',
     desc='the thickeness-chord ratios at station locations',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6112,7 +6113,7 @@
     historical_name={"GASP": 'INGASP.TCR', "FLOPS": None, "LEAPS1": None},
     units='unitless',
     desc='thickness-to-chord ratio at the root of the wing',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6142,7 +6143,7 @@
     },
     units='unitless',
     desc='structural ultimate load factor',
-    default_value=0.0,  # changed form 3.75
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6780,7 +6781,7 @@
     units='lbm',
     desc='fuel carried by the aircraft when it is on the ramp at the '
     'beginning of the design mission',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6790,7 +6791,7 @@
     units='lbm',
     desc='fuel carried by the aircraft when it is on the ramp at the '
     'beginning of the design mission',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6812,7 +6813,7 @@
     },
     units='lbm',
     desc='design gross mass of the aircraft',
-    default_value=0.0,  # changed from None
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -6870,7 +6871,7 @@
     },
     units='unitless',
     desc='aircraft design Mach number',
-    default_value=0.0,  # added
+    default_value=0.0,
 )
 
 add_meta_data(
@@ -7085,7 +7086,7 @@
     },
     units='unitless',
     desc='maximum lift coefficient for landing',
-    default_value=0.0,  # changed from 3.0
+    default_value=0.0,
 )
 
 add_meta_data(