http://s000.tinyupload.com/index.php?file_id=58028232103089441796

I make no claim or warranties for this, nor do I plan to troubleshoot it; i just got tired of playing without it.

Please note, that I havent tested anything other than research, build, fly, and enter/exit vehicle. None of the heliport/call helicopter functions have been tested.

Hello,
it works for the helicopter against the remote :

Error while running event Helicopters::on_gui_click (ID 1)
Unknown sprite "heli_to_character"
stack traceback:
Helicopters/logic/gui/heliSelectionGui.lua:323: in function 'buildGui'
Helicopters/logic/gui/heliSelectionGui.lua:24: in function 'new'
Helicopters/logic/gui/remoteGui.lua:77: in function 'new'
Helicopters/logic/gui/remoteGui.lua:34: in function 'toggleRemoteGui'
Helicopters/control.lua:245: in function <Helicopters/control.lua:238>
stack traceback:
[C]: in function 'add'
Helicopters/logic/gui/heliSelectionGui.lua:323: in function 'buildGui'
Helicopters/logic/gui/heliSelectionGui.lua:24: in function 'new'
Helicopters/logic/gui/remoteGui.lua:77: in function 'new'
Helicopters/logic/gui/remoteGui.lua:34: in function 'toggleRemoteGui'
Helicopters/control.lua:245: in function <Helicopters/control.lua:238>

I regularly have this error in flight:

2019/05/09 21:05:29 Factorio Server: 7110.646 Error MainLoop.cpp:1173: Exception at tick 21197769: The mod Helicopters caused a non-recoverable error.
2019/05/09 21:05:29 [7110.646 Error MainLoop.cpp:1173: Exception at tick 21197769: The mod Helicopters caused a non-recoverable error.]
2019/05/09 21:05:29 Factorio Server: Please report this error to the mod author.
2019/05/09 21:05:29 Factorio Server:
2019/05/09 21:05:29 Factorio Server: Error while running event Helicopters::on_tick (ID 0)
2019/05/09 21:05:29 Factorio Server: LuaEntity doesn't contain key is_character.
2019/05/09 21:05:29 Factorio Server: stack traceback:
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:181: in function 'extractcharacter'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:193: in function 'getCarcharacters'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:596: in function 'setFuelGaugeTarget'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:828: in function 'handleFuelConsumption'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:449: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:263: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:99: in function 'checkAndTickInGlobal'
2019/05/09 21:05:29 Factorio Server: Helicopters/control.lua:102: in function <Helicopters/control.lua:101>
2019/05/09 21:05:29 Factorio Server: stack traceback:
2019/05/09 21:05:29 Factorio Server: [C]: in function 'index'
2019/05/09 21:05:29 Factorio Server: __Helicopters/logic/util.lua:181: in function 'extractcharacter'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:193: in function 'getCarcharacters'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:596: in function 'setFuelGaugeTarget'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:828: in function 'handleFuelConsumption'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:449: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:263: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:99: in function 'checkAndTickInGlobal'
2019/05/09 21:05:29 Factorio Server: Helicopters/control.lua:102: in function <Helicopters/control.lua:101
2019/05/09 21:05:29 Factorio Server: 7110.646 Error ServerMultiplayerManager.cpp:92: MultiplayerManager failed: "The mod Helicopters caused a non-recoverable error.
2019/05/09 21:05:29 [7110.646 Error ServerMultiplayerManager.cpp:92: MultiplayerManager failed: "The mod Helicopters caused a non-recoverable error.]
2019/05/09 21:05:29 Factorio Server: Please report this error to the mod author.
2019/05/09 21:05:29 Factorio Server:
2019/05/09 21:05:29 Factorio Server: Error while running event Helicopters::on_tick (ID 0)
2019/05/09 21:05:29 Factorio Server: LuaEntity doesn't contain key is_character.
2019/05/09 21:05:29 Factorio Server: stack traceback:
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:181: in function 'extractcharacter'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:193: in function 'getCarcharacters'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:596: in function 'setFuelGaugeTarget'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:828: in function 'handleFuelConsumption'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:449: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:263: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:99: in function 'checkAndTickInGlobal'
2019/05/09 21:05:29 Factorio Server: Helicopters/control.lua:102: in function <Helicopters/control.lua:101>
2019/05/09 21:05:29 Factorio Server: stack traceback:
2019/05/09 21:05:29 Factorio Server: [C]: in function 'index'
2019/05/09 21:05:29 Factorio Server: __Helicopters/logic/util.lua:181: in function 'extractcharacter'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:193: in function 'getCarcharacters'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:596: in function 'setFuelGaugeTarget'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:828: in function 'handleFuelConsumption'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:449: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/heliBase.lua:263: in function 'OnTick'
2019/05/09 21:05:29 Factorio Server: Helicopters/logic/util.lua:99: in function 'checkAndTickInGlobal'
2019/05/09 21:05:29 Factorio Server: Helicopters/control.lua:102: in function <Helicopters/control.lua:101>
2019/05/09 21:05:29 Factorio Server: 7110.646 Info ServerMultiplayerManager.cpp:769: updateTick(21197769) changing state from(InGame) to(Failed)
2019/05/09 21:05:29 Factorio Server: 7110.661 Quitting: multiplayer error.

If you're looking at the github, someone made a pull to fix the 0.17.35+ changes while waiting Kumpu have free time to update this mod.
https://github.com/kumpuu/factorio-helicopters/pull/25
I just test it, and so far all function is working.

https://mods.factorio.com/mod/Helicopters/discussion/5cd696b863d5b1000dc855ea