Grumman seaplane + add-on - by "elcreador"
This mod replace cuban800 plane (or another plane).
Amphibious vehicle, with 3 weapons.
I hope you like.

files:
-replace folder
-add-on folder (with install instructions)

Installation:
With OpenIV in edit mode replace the files:

The model files(cuban800.yft-cuban800_hi.yft-cuban800.ytd) get into:
\GTA V\x64e.rpf\levels\gta5\vehicles.rpf\

Replace the handling.meta in:
GTA V\update\update.rpf\common\data

Replace the vehicle.meta in:
GTA V\update\update.rpf\common\data\levels\gta5

---------------------------------------------------------------------------

You can either replace only the vehicles lines editing the files:

In vehicle.meta:
Extract it with OpenIV and edit it with Notepad++. Open the file, press CTRL+F and search for "titan" until you find the part where cuban800 is listed 4 times.

Overwrite original entry with the following:

<modelName>cuban800</modelName>
      <txdName>cuban800</txdName>
      <handlingId>CUBAN800</handlingId>
      <gameName>CUBAN800</gameName>
      <vehicleMakeName />
      <expressionDictName>null</expressionDictName>
      <expressionName>null</expressionName>
      <animConvRoofDictName>va_cuban800</animConvRoofDictName>
      <animConvRoofName>drophatch</animConvRoofName>
      <animConvRoofWindowsAffected />
      <ptfxAssetName>null</ptfxAssetName>
      <audioNameHash />
      <layout>LAYOUT_VAN</layout>
      <coverBoundOffsets>STANDARD_COVER_OFFSET_INFO</coverBoundOffsets>
      <explosionInfo>EXPLOSION_INFO_TITAN</explosionInfo>
      <scenarioLayout />
      <cameraName>FOLLOW_TITAN_CAMERA</cameraName>
      <aimCameraName>TITAN_AIM_CAMERA</aimCameraName>
      <bonnetCameraName>TITAN_BONNET_CAMERA</bonnetCameraName>
      <povCameraName>PLANE_POV_CAMERA</povCameraName>
      <FirstPersonDriveByIKOffset x="0.000000" y="0.000000" z="0.000000" />
      <FirstPersonDriveByUnarmedIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonProjectileDriveByIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonProjectileDriveByPassengerIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonProjectileDriveByRearLeftIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonProjectileDriveByRearRightIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonDriveByLeftPassengerIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonDriveByRightPassengerIKOffset x="0.000000" y="-0.038000" z="-0.045000" />
	  <FirstPersonDriveByRightRearPassengerIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonDriveByLeftPassengerUnarmedIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonDriveByRightPassengerUnarmedIKOffset x="0.000000" y="0.000000" z="0.000000" />
	  <FirstPersonMobilePhoneOffset x="0.165000" y="0.360000" z="0.558000" />
      <FirstPersonPassengerMobilePhoneOffset x="0.189000" y="0.291000" z="0.515000" />
      <PovCameraOffset x="0.000000" y="-0.050000" z="0.700000" />
      <PovCameraVerticalAdjustmentForRollCage value="0.000000" />
      <PovPassengerCameraOffset x="0.000000" y="0.100000" z="0.140000" />
      <PovRearPassengerCameraOffset x="0.000000" y="0.100000" z="0.140000" />
      <vfxInfoName>VFXVEHICLEINFO_PLANE_TITAN</vfxInfoName>
      <shouldUseCinematicViewMode value="true" />
      <shouldCameraTransitionOnClimbUpDown value="true" />
      <shouldCameraIgnoreExiting value="false" />
      <AllowPretendOccupants value="false" />
      <AllowJoyriding value="true" />
      <AllowSundayDriving value="true" />
      <AllowBodyColorMapping value="true" />
      <wheelScale value="0.200100" />
      <wheelScaleRear value="0.117600" />
      <dirtLevelMin value="0.000000" />
      <dirtLevelMax value="0.450000" />
      <envEffScaleMin value="0.500000" />
      <envEffScaleMax value="0.700000" />
      <envEffScaleMin2 value="0.500000" />
      <envEffScaleMax2 value="0.700000" />
      <damageMapScale value="0.600000" />
      <damageOffsetScale value="1.000000" />
      <diffuseTint value="0x00FFFFFF" />
      <steerWheelMult value="1.000000" />
      <HDTextureDist value="5.000000" />
      <lodDistances content="float_array">
        50.000000
        80.000000
        150.000000
        300.000000
        1000.000000
        1000.000000
      </lodDistances>
      <minSeatHeight value="1.715" />
      <identicalModelSpawnDistance value="20" />
      <maxNumOfSameColor value="10" />
      <defaultBodyHealth value="1000.000000" />
      <pretendOccupantsScale value="1.000000" />
      <visibleSpawnDistScale value="2.750000" />
      <trackerPathWidth value="2.000000" />
      <weaponForceMult value="1.000000" />
      <frequency value="100" />
      <swankness>SWANKNESS_4</swankness>
      <maxNum value="999" />
      <flags>FLAG_NO_BOOT FLAG_DRIVER_NO_DRIVE_BY FLAG_DONT_SPAWN_IN_CARGEN FLAG_DONT_SPAWN_AS_AMBIENT FLAG_BLOCK_FROM_ATTRACTOR_SCENARIO FLAG_DONT_TIMESLICE_WHEELS FLAG_USE_LIGHTING_INTERIOR_OVERRIDE FLAG_USE_PILOT_HELMET</flags>
      <type>VEHICLE_TYPE_PLANE</type>
      <plateType>VPT_NONE</plateType>
      <dashboardType>VDT_MAVERICK</dashboardType>
      <vehicleClass>VC_PLANE</vehicleClass>
      <wheelType>VWT_SPORT</wheelType>
      <trailers />
      <additionalTrailers />
      <drivers>
        <Item>
          <driverName>S_M_M_Gentransport</driverName>
          <npcName>Pilot</npcName>
        </Item>
      </drivers>
      <extraIncludes />
      <doorsWithCollisionWhenClosed>
        <Item>VEH_EXT_BOOT</Item>
      </doorsWithCollisionWhenClosed>
      <driveableDoors>
        <Item>VEH_EXT_BOOT</Item>
      </driveableDoors>
      <bumpersNeedToCollideWithMap value="false" />
      <needsRopeTexture value="false" />
      <requiredExtras />
      <rewards />
      <cinematicPartCamera>
        <Item>TITAN_WINGLIGHT_LEFT_CAMERA</Item>
        <Item>TITAN_WINGLIGHT_RIGHT_CAMERA</Item>
        <Item>TITAN_TAIL_LEFT_CAMERA</Item>
        <Item>TITAN_TAIL_RIGHT_CAMERA</Item>
      </cinematicPartCamera>
      <NmBraceOverrideSet />
      <buoyancySphereOffset x="0.000000" y="0.000000" z="0.000000" />
      <buoyancySphereSizeScale value="1.000000" />
      <pOverrideRagdollThreshold type="NULL" />
      <firstPersonDrivebyData>
        <Item>STD_FRONT_LEFT</Item>
        <Item>PLANE_FRONT_RIGHT</Item>
      </firstPersonDrivebyData>
	  <lockOnPositionOffset x="0.000000" y="0.000000" z="-2.500000" />
    </Item>





---------------------------------------------------------------------------


HANDLING WITH SLOW SPEED
In handling.meta:

Extract it with OpenIV and edit it with Notepad++. Open the file, press CTRL+F and search for "titan" and overwrite the nexts lines.

<handlingName>cuban800</handlingName>
      <fMass value="11000.000000" />
      <fInitialDragCoeff value="8.000000" />
      <fPercentSubmerged value="5.000000" />
      <vecCentreOfMassOffset x="0.000000" y="0.000000" z="0.000000" />
      <vecInertiaMultiplier x="1.000000" y="1.000000" z="1.000000" />
      <fDriveBiasFront value="0.000000" />
      <nInitialDriveGears value="1" />
      <fInitialDriveForce value="0.010000" />
      <fDriveInertia value="1.000000" />
      <fClutchChangeRateScaleUpShift value="1.300000" />
      <fClutchChangeRateScaleDownShift value="1.300000" />
      <fInitialDriveMaxFlatVel value="268.700000" />
      <fBrakeForce value="0.050000" />
      <fBrakeBiasFront value="0.600000" />
      <fHandBrakeForce value="0.010000" />
      <fSteeringLock value="35.000000" />
      <fTractionCurveMax value="2.150000" />
      <fTractionCurveMin value="1.800000" />
      <fTractionCurveLateral value="12.000000" />
      <fTractionSpringDeltaMax value="0.100000" />
      <fLowSpeedTractionLossMult value="0.000000" />
      <fCamberStiffnesss value="0.000000" />
      <fTractionBiasFront value="0.500000" />
      <fTractionLossMult value="0.000000" />
      <fSuspensionForce value="6.500000" />
      <fSuspensionCompDamp value="6.300000" />
      <fSuspensionReboundDamp value="6.400000" />
      <fSuspensionUpperLimit value="0.080000" />
      <fSuspensionLowerLimit value="-0.080000" />
      <fSuspensionRaise value="0.000000" />
      <fSuspensionBiasFront value="0.600000" />
      <fAntiRollBarForce value="0.000000" />
      <fAntiRollBarBiasFront value="0.000000" />
      <fRollCentreHeightFront value="0.800000" />
      <fRollCentreHeightRear value="0.800000" />
      <fCollisionDamageMult value="1.500000" />
      <fWeaponDamageMult value="0.500000" />
      <fDeformationDamageMult value="4.000000" />
      <fEngineDamageMult value="1.500000" />
      <fPetrolTankVolume value="65.000000" />
      <fOilVolume value="5.000000" />
      <fSeatOffsetDistX value="0.000000" />
      <fSeatOffsetDistY value="0.000000" />
      <fSeatOffsetDistZ value="0.000000" />
      <nMonetaryValue value="45000" />
      <strModelFlags>1000000</strModelFlags>
      <strHandlingFlags>400100</strHandlingFlags>
      <strDamageFlags>20</strDamageFlags>
      <AIHandling>AVERAGE</AIHandling>
      <SubHandlingData>
        <Item type="CFlyingHandlingData">
          <fThrust value="0.620000" />
          <fThrustFallOff value="0.000100" />
          <fThrustVectoring value="0.000000" />
          <fYawMult value="-0.001550" />
          <fYawStabilise value="0.001000" />
          <fSideSlipMult value="0.055000" />
          <fRollMult value="0.003750" />
          <fRollStabilise value="-0.000000" />
          <fPitchMult value="0.001000" />
          <fPitchStabilise value="0.001000" />
          <fFormLiftMult value="0.000180" />
          <fAttackLiftMult value="0.014000" />
          <fAttackDiveMult value="0.014000" />
          <fGearDownDragV value="0.070000" />
          <fGearDownLiftMult value="0.900000" />
          <fWindMult value="0.000000" />
          <fMoveRes value="0.001000" />
          <vecTurnRes x="0.200000" y="0.600000" z="0.500000" />
          <vecSpeedRes x="0.060000" y="0.060000" z="0.060000" />
          <fGearDoorFrontOpen value="90.000000" />
          <fGearDoorRearOpen value="89.949997" />
          <fGearDoorRearOpen2 value="89.949997" />
          <fGearDoorRearMOpen value="89.949997" />
          <fTurublenceMagnitudeMax value="10.000000" />
          <fTurublenceForceMulti value="0.000050" />
          <fTurublenceRollTorqueMulti value="0.010000" />
          <fTurublencePitchTorqueMulti value="0.002000" />
          <fBodyDamageControlEffectMult value="0.100000" />
          <fInputSensitivityForDifficulty value="0.240000" />
          <fOnGroundYawBoostSpeedPeak value="3.000000" />
          <fOnGroundYawBoostSpeedCap value="6.000000" />
          <fEngineOffGlideMulti value="1.000000" />
          <handlingType>HANDLING_TYPE_FLYING</handlingType>
		</Item>
        <Item type="CSeaPlaneHandlingData">
	  <fLeftPontoonComponentId value="13"/>
	  <fRightPontoonComponentId value="13"/>
	  <fPontoonBuoyConst value="50.0"/>
	  <fPontoonSampleSizeFront value="0.9"/>
	  <fPontoonSampleSizeMiddle value="0.3"/>
	  <fPontoonSampleSizeRear value="0.6"/>
	  <fPontoonLengthFractionForSamples value="0.95"/>
	  <fPontoonDragCoefficient value="1.0"/>
	  <fPontoonVerticalDampingCoefficientUp value="1000.0"/>
	  <fPontoonVerticalDampingCoefficientDown value="1000.0"/>
	  <fKeelSphereSize value="0.0"/>
        </Item>
        <Item type="CFlyingHandlingData">
          <fThrust value="1.400000" />
          <fThrustFallOff value="0.050000" />
          <fThrustVectoring value="0.800000" />
          <fYawMult value="-3.000000" />
          <fYawStabilise value="0.001000" />
          <fSideSlipMult value="0.004000" />
          <fRollMult value="0.900000" />
          <fRollStabilise value="0.012000" />
          <fPitchMult value="0.700000" />
          <fPitchStabilise value="0.004000" />
          <fFormLiftMult value="0.600000" />
          <fAttackLiftMult value="2.500000" />
          <fAttackDiveMult value="2.500000" />
          <fGearDownDragV value="0.100000" />
          <fGearDownLiftMult value="1.000000" />
          <fWindMult value="0.000150" />
          <fMoveRes value="0.000500" />
          <vecTurnRes x="2.800000" y="2.700000" z="2.800000" />
          <vecSpeedRes x="0.500000" y="0.500000" z="0.700000" />
          <fGearDoorFrontOpen value="90.000000" />
          <fGearDoorRearOpen value="90.000000" />
          <fGearDoorRearOpen2 value="90.000000" />
          <fGearDoorRearMOpen value="90.000000" />
          <fTurublenceMagnitudeMax value="0.000000" />
          <fTurublenceForceMulti value="0.000000" />
          <fTurublenceRollTorqueMulti value="0.005000" />
          <fTurublencePitchTorqueMulti value="0.000000" />
          <fBodyDamageControlEffectMult value="0.100000" />
          <fInputSensitivityForDifficulty value="1.000000" />
          <fOnGroundYawBoostSpeedPeak value="1.000000" />
          <fOnGroundYawBoostSpeedCap value="0.000000" />
          <fEngineOffGlideMulti value="0.000000" />
          <handlingType>HANDLING_TYPE_VERTICAL_FLYING</handlingType>
        </Item>
        <Item type="CVehicleWeaponHandlingData">
          <uWeaponHash>
            <Item>VEHICLE_WEAPON_PLAYER_SAVAGE</Item>
            <Item>VEHICLE_WEAPON_SPACE_ROCKET</Item>
            <Item>VEHICLE_WEAPON_TANK</Item>
            <Item />
          </uWeaponHash>
          <WeaponSeats content="int_array">
            0 
            0 
            0 
          </WeaponSeats>
          <fTurretSpeed content="float_array">
            0.000000	
            0.000000	
          </fTurretSpeed>
          <fTurretPitchMin content="float_array">
            0.000000	
            0.000000	
          </fTurretPitchMin>
          <fTurretPitchMax content="float_array">
            0.000000	
            0.000000	
          </fTurretPitchMax>
          <fTurretCamPitchMin content="float_array">
            0.000000	
            0.000000	
          </fTurretCamPitchMin>
          <fTurretCamPitchMax content="float_array">
            0.000000	
            0.000000	
          </fTurretCamPitchMax>
          <fBulletVelocityForGravity content="float_array">
            0.000000	
            0.000000	
          </fBulletVelocityForGravity>
          <fTurretPitchForwardMin content="float_array">
            0.000000	
            0.000000	
          </fTurretPitchForwardMin>
          <fUvAnimationMult value="0.000000" />
          <fMiscGadgetVar value="0.000000" />
          <fWheelImpactOffset value="0.000000" />
        </Item>
        <Item type="NULL" />
        <Item type="NULL" />
      </SubHandlingData>
    </Item>
