diff --git a/Manifest-v1.11.toml.default b/Manifest-v1.11.toml.default
index a8077902..0adef93d 100644
--- a/Manifest-v1.11.toml.default
+++ b/Manifest-v1.11.toml.default
@@ -2,7 +2,7 @@
 
 julia_version = "1.11.5"
 manifest_format = "2.0"
-project_hash = "f9f7424be55e7c582f860e66512280fdde05365c"
+project_hash = "68e47961fc0a02ad352b159a56f527bb8f6669a3"
 
 [[deps.ADTypes]]
 git-tree-sha1 = "e2478490447631aedba0823d4d7a80b2cc8cdb32"
@@ -187,11 +187,6 @@ weakdeps = ["ChainRulesCore", "ForwardDiff"]
     BracketingNonlinearSolveChainRulesCoreExt = ["ChainRulesCore", "ForwardDiff"]
     BracketingNonlinearSolveForwardDiffExt = "ForwardDiff"
 
-[[deps.CEnum]]
-git-tree-sha1 = "389ad5c84de1ae7cf0e28e381131c98ea87d54fc"
-uuid = "fa961155-64e5-5f13-b03f-caf6b980ea82"
-version = "0.5.0"
-
 [[deps.CPUSummary]]
 deps = ["CpuId", "IfElse", "PrecompileTools", "Static"]
 git-tree-sha1 = "5a97e67919535d6841172016c9530fd69494e5ec"
@@ -613,9 +608,9 @@ uuid = "4e289a0a-7415-4d19-859d-a7e5c4648b56"
 version = "1.0.5"
 
 [[deps.EnzymeCore]]
-git-tree-sha1 = "7d7822a643c33bbff4eab9c87ca8459d7c688db0"
+git-tree-sha1 = "8272a687bca7b5c601c0c24fc0c71bff10aafdfd"
 uuid = "f151be2c-9106-41f4-ab19-57ee4f262869"
-version = "0.8.11"
+version = "0.8.12"
 weakdeps = ["Adapt"]
 
     [deps.EnzymeCore.extensions]
@@ -790,9 +785,9 @@ uuid = "d25df0c9-e2be-5dd7-82c8-3ad0b3e990b9"
 version = "0.1.5"
 
 [[deps.InlineStrings]]
-git-tree-sha1 = "6a9fde685a7ac1eb3495f8e812c5a7c3711c2d5e"
+git-tree-sha1 = "8594fac023c5ce1ef78260f24d1ad18b4327b420"
 uuid = "842dd82b-1e85-43dc-bf29-5d0ee9dffc48"
-version = "1.4.3"
+version = "1.4.4"
 weakdeps = ["ArrowTypes", "Parsers"]
 
     [deps.InlineStrings.extensions]
@@ -1906,18 +1901,6 @@ deps = ["Artifacts", "Libdl", "libblastrampoline_jll"]
 uuid = "bea87d4a-7f5b-5778-9afe-8cc45184846c"
 version = "7.7.0+0"
 
-[[deps.Sundials]]
-deps = ["CEnum", "DataStructures", "DiffEqBase", "Libdl", "LinearAlgebra", "Logging", "PrecompileTools", "Reexport", "SciMLBase", "SparseArrays", "Sundials_jll"]
-git-tree-sha1 = "7c7a7ee705724b3c80d5451ac49779db36c6f758"
-uuid = "c3572dad-4567-51f8-b174-8c6c989267f4"
-version = "4.28.0"
-
-[[deps.Sundials_jll]]
-deps = ["Artifacts", "CompilerSupportLibraries_jll", "JLLWrappers", "Libdl", "SuiteSparse_jll", "libblastrampoline_jll"]
-git-tree-sha1 = "91db7ed92c66f81435fe880947171f1212936b14"
-uuid = "fb77eaff-e24c-56d4-86b1-d163f2edb164"
-version = "5.2.3+0"
-
 [[deps.SymbolicIndexingInterface]]
 deps = ["Accessors", "ArrayInterface", "PrettyTables", "RuntimeGeneratedFunctions", "StaticArraysCore"]
 git-tree-sha1 = "b6a641e38efa01355aa721246dd246e10c7dcd4d"
diff --git a/Project.toml b/Project.toml
index d98f3d9d..be97c375 100644
--- a/Project.toml
+++ b/Project.toml
@@ -35,7 +35,6 @@ Serialization = "9e88b42a-f829-5b0c-bbe9-9e923198166b"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
-Sundials = "c3572dad-4567-51f8-b174-8c6c989267f4"
 SymbolicIndexingInterface = "2efcf032-c050-4f8e-a9bb-153293bab1f5"
 SymbolicUtils = "d1185830-fcd6-423d-90d6-eec64667417b"
 Timers = "21f18d07-b854-4dab-86f0-c15a3821819a"
@@ -90,7 +89,6 @@ Serialization = "1.10, 1.11"
 StaticArrays = "1.9.7"
 Statistics = "1"
 StatsBase = "0.34"
-Sundials = "4.24"
 SymbolicIndexingInterface = "0.3"
 SymbolicUtils = "3.25"
 Test = "1"
@@ -104,6 +102,7 @@ Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
 Colors = "5ae59095-9a9b-59fe-a467-6f913c188581"
 ControlPlots = "23c2ee80-7a9e-4350-b264-8e670f12517c"
+ControlSystemsBase = "aaaaaaaa-a6ca-5380-bf3e-84a91bcd477e"
 DSP = "717857b8-e6f2-59f4-9121-6e50c889abd2"
 Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 JLD2 = "033835bb-8acc-5ee8-8aae-3f567f8a3819"
@@ -111,7 +110,6 @@ LaTeXStrings = "b964fa9f-0449-5b57-a5c2-d3ea65f4040f"
 PackageCompiler = "9b87118b-4619-50d2-8e1e-99f35a4d4d9d"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
-ControlSystemsBase = "aaaaaaaa-a6ca-5380-bf3e-84a91bcd477e"
 
 [targets]
 test = ["Test", "BenchmarkTools", "PackageCompiler", "Documenter", "ControlPlots", "Colors", "LaTeXStrings", "StatsBase", "JLD2", "Aqua", "DSP", "ControlSystemsBase"]
diff --git a/examples_3d/Project.toml b/examples_3d/Project.toml
index cd6e1c9b..b0aa4321 100644
--- a/examples_3d/Project.toml
+++ b/examples_3d/Project.toml
@@ -24,7 +24,6 @@ Rotations = "6038ab10-8711-5258-84ad-4b1120ba62dc"
 Serialization = "9e88b42a-f829-5b0c-bbe9-9e923198166b"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 SteadyStateDiffEq = "9672c7b4-1e72-59bd-8a11-6ac3964bc41f"
-Sundials = "c3572dad-4567-51f8-b174-8c6c989267f4"
 SymbolicIndexingInterface = "2efcf032-c050-4f8e-a9bb-153293bab1f5"
 Timers = "21f18d07-b854-4dab-86f0-c15a3821819a"
 WinchModels = "7dcfa46b-7979-4771-bbf4-0aee0da42e1f"
@@ -51,7 +50,6 @@ Reexport = "1.1, 1.2"
 Rotations = "1.3"
 StaticArrays = "1.9"
 SteadyStateDiffEq = "2.3.0"
-Sundials = "4.24"
 SymbolicIndexingInterface = "0.3.27"
 Timers = "0.1.5"
 WinchModels = "0.3.3"
diff --git a/mwes/mwe_03.jl b/mwes/mwe_03.jl
index c72d7888..950790e9 100644
--- a/mwes/mwe_03.jl
+++ b/mwes/mwe_03.jl
@@ -6,7 +6,7 @@ using Pkg
 if ! ("ControlPlots" ∈ keys(Pkg.project().dependencies))
     using TestEnv; TestEnv.activate()
 end
-using Sundials, ControlPlots
+using ControlPlots
 
 const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
 const dt = 0.05
@@ -34,7 +34,7 @@ function solve(integrator, dt, t_final)
     time=Float64[]
     for t in 0:0.05:t_final    
         push!(time, t)
-        Sundials.step!(integrator, dt, true)
+        step!(integrator, dt, true)
         push!(pos_z, integrator.u[3])
         push!(vel_z, integrator.u[6])
     end
@@ -56,7 +56,7 @@ abstol  = 0.0006 # max error in m/s and m
 s = nothing
 
 prob    = DAEProblem(res!, yd0, y0, tspan, s, differential_vars=differential_vars)
-integrator = Sundials.init(prob, solver, abstol, reltol=0.001)
+integrator = init(prob, solver, abstol, reltol=0.001)
 
 @time time_, pos_z, vel_z = solve(integrator, dt, t_final)
 
diff --git a/mwes/mwe_04.jl b/mwes/mwe_04.jl
index c8d57e61..c45c8ed5 100644
--- a/mwes/mwe_04.jl
+++ b/mwes/mwe_04.jl
@@ -6,7 +6,7 @@ using Pkg
 if ! ("ControlPlots" ∈ keys(Pkg.project().dependencies))
     using TestEnv; TestEnv.activate()
 end
-using Sundials, ControlPlots
+using ControlPlots
 
 const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
 const dt = 0.05
@@ -35,7 +35,7 @@ end
 function solve!(res, integrator, dt, t_final)
     for (i,t) in pairs(0:dt:t_final)
         res.time[i] = t
-        Sundials.step!(integrator, dt, true)
+        step!(integrator, dt, true)
         res.pos_z[i] = integrator.u[3]
         res.vel_z[i] = integrator.u[6]
     end
@@ -56,7 +56,7 @@ function init()
     s = nothing
 
     prob    = DAEProblem(res!, yd0, y0, tspan, s, differential_vars=differential_vars)
-    integrator = Sundials.init(prob, solver, abstol, reltol=0.001, save_everystep=false)
+    integrator = init(prob, solver, abstol, reltol=0.001, save_everystep=false)
 end
 
 function plot(res::Result)
diff --git a/mwes/mwe_05.jl b/mwes/mwe_05.jl
index c71c4379..e6116171 100644
--- a/mwes/mwe_05.jl
+++ b/mwes/mwe_05.jl
@@ -6,7 +6,7 @@ using Pkg
 if ! ("ControlPlots" ∈ keys(Pkg.project().dependencies))
     using TestEnv; TestEnv.activate()
 end
-using Sundials, ControlPlots
+using ControlPlots
 
 const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
 const dt = 0.05
diff --git a/mwes/mwe_07.jl b/mwes/mwe_07.jl
index 22b1a894..03c3cfd9 100644
--- a/mwes/mwe_07.jl
+++ b/mwes/mwe_07.jl
@@ -6,7 +6,7 @@ using Pkg
 if ! ("ControlPlots" ∈ keys(Pkg.project().dependencies))
     using TestEnv; TestEnv.activate()
 end
-using ControlPlots, OrdinaryDiffEq, Sundials #, DASKR
+using ControlPlots, OrdinaryDiffEq #, DASKR
 
 const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
 const dt = 0.05
diff --git a/mwes/mwe_08.jl b/mwes/mwe_08.jl
index b3d5ee5b..cbb037d8 100644
--- a/mwes/mwe_08.jl
+++ b/mwes/mwe_08.jl
@@ -6,7 +6,7 @@ using Pkg
 if ! ("ControlPlots" ∈ keys(Pkg.project().dependencies))
     using TestEnv; TestEnv.activate()
 end
-using ControlPlots, OrdinaryDiffEq, Sundials
+using ControlPlots, OrdinaryDiffEq
 
 const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
 const dt = 0.05
diff --git a/mwes/mwe_09.jl b/mwes/mwe_09.jl
index 153ddafe..402b19bc 100644
--- a/mwes/mwe_09.jl
+++ b/mwes/mwe_09.jl
@@ -9,7 +9,7 @@ end
 if ! ("OrdinaryDiffEq" ∈ keys(Pkg.project().dependencies))
     Pkg.add("OrdinaryDiffEq")
 end
-using OrdinaryDiffEq, ControlPlots, Sundials, StaticArrays
+using OrdinaryDiffEq, ControlPlots, StaticArrays
 
 STATIC_ARRAYS::Bool = false
 if STATIC_ARRAYS
diff --git a/src/KiteModels.jl b/src/KiteModels.jl
index f55922d3..c21afaf2 100644
--- a/src/KiteModels.jl
+++ b/src/KiteModels.jl
@@ -16,7 +16,6 @@ using PrecompileTools: @setup_workload, @compile_workload
 using Dierckx, Interpolations, Serialization, StaticArrays, LinearAlgebra, Statistics, Parameters, NLsolve,
       DocStringExtensions, OrdinaryDiffEqCore, OrdinaryDiffEqBDF, OrdinaryDiffEqNonlinearSolve,
       NonlinearSolve
-import Sundials
 using Reexport, Pkg
 using VortexStepMethod
 @reexport using VortexStepMethod: RamAirWing, BodyAerodynamics, Solver, NONLIN
@@ -580,9 +579,7 @@ function init_sim!(s::AKM; stiffness_factor=0.5, delta=0.0001, upwind_dir=-pi/2,
     y0  = Vector{SimFloat}(y0)
     yd0 = Vector{SimFloat}(yd0)
     
-    if s.set.solver=="IDA"
-        solver  = Sundials.IDA(linear_solver=Symbol(s.set.linear_solver), max_order = s.set.max_order)
-    elseif s.set.solver=="DImplicitEuler"
+    if s.set.solver=="DImplicitEuler"
         solver  = DImplicitEuler(autodiff=AutoFiniteDiff())
     elseif s.set.solver=="DFBDF"
         solver  = DFBDF(autodiff=AutoFiniteDiff(), max_order=Val{s.set.max_order}())        
@@ -646,11 +643,7 @@ function next_step!(s::AKM, integrator; set_speed = nothing, set_torque=nothing,
     s.t_0 = integrator.t
     set_v_wind_ground!(s, calc_height(s), v_wind_gnd; upwind_dir)
     s.iter = 0
-    if s.set.solver == "IDA"
-        Sundials.step!(integrator, dt, true)
-    else
-        OrdinaryDiffEqCore.step!(integrator, dt, true)
-    end
+    OrdinaryDiffEqCore.step!(integrator, dt, true)
     if s.stiffness_factor < 1.0
         s.stiffness_factor+=0.01
         if s.stiffness_factor > 1.0
diff --git a/test/create_sys_image.jl b/test/create_sys_image.jl
index 0b47f76b..ba1e01b5 100644
--- a/test/create_sys_image.jl
+++ b/test/create_sys_image.jl
@@ -8,7 +8,7 @@ if ! ("PackageCompiler" ∈ keys(Pkg.project().dependencies))
     Pkg.update()
 end
 @info "Loading packages ..."
-using Dierckx, StaticArrays, LinearAlgebra, Parameters, NLsolve, DocStringExtensions, Sundials, KiteUtils, 
+using Dierckx, StaticArrays, LinearAlgebra, Parameters, NLsolve, DocStringExtensions, KiteUtils, 
       KitePodModels, AtmosphericModels, OrdinaryDiffEqCore, OrdinaryDiffEqBDF, ModelingToolkit,
       DSP, JLD2, Colors, REPL, VortexStepMethod, NonlinearSolve, OrdinaryDiffEqNonlinearSolve, StatsBase,
       DiscretePIDs, WinchModels, ControlSystemsBase
@@ -18,7 +18,7 @@ using PackageCompiler, BenchmarkTools, Documenter
 push!(LOAD_PATH,joinpath(pwd(),"src"))
 
 PackageCompiler.create_sysimage(
-    [:Dierckx, :StaticArrays, :Parameters, :NLsolve, :DocStringExtensions, :Sundials, :KiteUtils, 
+    [:Dierckx, :StaticArrays, :Parameters, :NLsolve, :DocStringExtensions, :KiteUtils, 
      :KitePodModels, :AtmosphericModels, :OrdinaryDiffEqCore, :OrdinaryDiffEqBDF, :WinchModels,
      :OrdinaryDiffEqNonlinearSolve, :StatsBase, :PackageCompiler, :BenchmarkTools, :Documenter,
      :ModelingToolkit, :JLD2, :Colors, :REPL, :VortexStepMethod, :NonlinearSolve, :DSP, :DiscretePIDs, 
diff --git a/test/test_sundials.jl b/test/test_sundials.jl
deleted file mode 100644
index 25306fb5..00000000
--- a/test/test_sundials.jl
+++ /dev/null
@@ -1,34 +0,0 @@
-# SPDX-FileCopyrightText: 2025 Uwe Fechner
-# SPDX-License-Identifier: MIT
-
-# unittest for Sundials.jl, works fine with 4.11.4 and older
-# also requires v6.115.4 of DiffEqBase or older
-using StaticArrays, Sundials, Test
-
-const KVec3    = MVector{3, Float64}
-
-Base.@kwdef mutable struct KPS4{S, T, P}
-    v_apparent::T =       zeros(S, 3)
-end
-
-const kps4 = KPS4{Float64, KVec3, 6+4+1}()
-
-function residual!(res, yd, y::MVector{S, Float64}, s::KPS4, time) where S
-end
-
-function init_sim!(t_end=1.0)
-    y0 = MVector{62, Float64}([13.970413450119487, 0.0, 21.238692070636343, 27.65581376097752, 0.0, 42.66213714321849, 40.976226230518435, 0.0, 64.314401166278, 53.87184032029182, 0.0, 86.22231803750196, 66.28915240374937, 0.0, 108.4048292516046, 78.17713830204762, 0.0, 130.87545423106485, 79.56930502428155, 0.0, 135.70836376062155, 80.90383289255747, 0.0, 137.7696816741141, 80.60126812407692, 2.4016533873456325, 135.3023287520457, 80.60126812407692, -2.4016533873456325, 135.3023287520457, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 150.0, 0.0])
-    yd0= MVector{62, Float64}([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0, -9.81, 0.0, 0.0])
-    differential_vars = ones(Bool, length(y0))
-    solver  = IDA(linear_solver=Symbol("GMRES"), max_order = 4)
-    tspan   = (0.0, t_end) 
-    abstol  = 0.0006 # max error in m/s and m
-    prob    = DAEProblem(residual!, yd0, y0, tspan, kps4, differential_vars=differential_vars)
-    integrator = Sundials.init(prob, solver, abstol=abstol, reltol=0.001)
-end
-
-@testset "test_simulate        " begin
-    STEPS = 500
-    integrator = init_sim!()
-end
-nothing