What does cold and dark mean in a flight simulator? Learn which systems are off, how start states differ and what must happen before taxi.
In a flight simulator, “cold and dark” means the aircraft is parked with its engines shut down and most electrical, avionics and cockpit systems switched off. You must establish electrical power, configure essential systems and start the engines before taxiing. The exact starting state varies by aircraft and add-on.
This is a general flight-simulation term used across Microsoft Flight Simulator, X-Plane, Prepar3D and other simulators; it is not one standardised aircraft state. “Cold” refers to the engines being stopped, while “dark” describes the unpowered instruments and displays. It does not refer to weather, daylight or simulated engine temperature.
What is switched off in a cold and dark cockpit?
A cold and dark aircraft normally has its main power sources, engines and operational systems switched off.
- Engines and, on applicable aircraft, the auxiliary power unit are stopped.
- The battery or electrical master is off, and generators or alternators are not supplying power.
- Avionics, radios, navigation displays and most cockpit screens are unpowered.
- Fuel pumps, hydraulic pumps, pneumatic bleed systems and ignition are normally off where fitted.
- Exterior and cockpit lighting is usually off.
Not every switch must be off. Clocks, emergency lighting, fire detection or standby equipment may use an independent or hot-battery supply. The aircraft can still contain fuel and payload, have wheel chocks fitted, or have a ground power unit connected but not selected.
How is cold and dark different from engines off?
“Engines off” only describes the engines, whereas cold and dark also implies that most cockpit and aircraft systems have been shut down.
| Aircraft state | Engines | Electrical and avionics |
|---|---|---|
| Cold and dark | Off | Mostly off and unpowered |
| Powered, engines off | Off | Battery, external power or APU supplying systems |
| Ready for taxi | Running | Configured for ground movement |
| Runway start | Usually running | Configured for immediate departure |
Do not confuse the phrase with the aviation “dark cockpit” philosophy. In that context, extinguished warning lights indicate that an operating aircraft is configured normally; it does not mean the cockpit lacks power.
Does cold and dark mean the same thing in every simulator?
The broad meaning is consistent, but the simulated switch positions and shutdown depth depend on the aircraft and software.
A simplified default aircraft may only stop the engines and blank the main displays. A detailed add-on can retain circuit-breaker logic, battery charge, fuel lever positions and a persistent aircraft state from the previous flight. Some models also provide their own state selector through a cockpit tablet, flight-management system or configuration panel.
Departure position matters as well. A gate or parking stand commonly loads an aircraft shut down, while a runway start usually provides a running, configured aircraft. We recommend selecting an explicit cold-and-dark preset when available rather than assuming every parking spawn uses one.
What should you do after loading cold and dark?
You should follow the aircraft’s checklist to establish power, prepare the starting systems and start the engines in the correct order.
- Secure the aircraft. Set the parking brake and use wheel chocks if the model supports them.
- Establish electrical power. Select the battery, external power or another source specified by the checklist.
- Prepare for starting. Configure fuel, ignition, pumps, APU and pneumatic systems as applicable.
- Start the engine or engines. Piston, turboprop and jet procedures differ substantially.
- Complete the after-start checks. Confirm generators, flight controls, instruments, lights and ground equipment before taxiing.
Our general cold-and-dark power-up procedure explains this sequence in more detail. For the differences between powerplants, see our guidance on starting piston, turboprop and jet engines. Airliner users can also follow the battery, APU, bleed-air and engine-start sequence for a Boeing 737.
Why will a cold and dark aircraft not power up?
A cold and dark aircraft usually remains unpowered because no usable electrical source has been connected and selected.
- Ground power is connected but not selected: connecting a unit does not necessarily energise the aircraft.
- The battery is depleted: detailed aircraft may simulate discharge and require external power or an aircraft-specific maintenance reset.
- The APU is running without its generator: starting the APU does not always connect it to the electrical buses automatically.
- Fuel or start controls remain in cutoff: check fuel selectors, mixture, condition levers, magnetos and ignition as appropriate.
- A hardware binding is overriding the cockpit: duplicate battery, avionics or fuel-cutoff assignments can continuously send an unwanted switch position.
- The automatic-start command is incomplete: detailed aircraft may ignore it or start the engines while leaving other systems incorrectly configured.
A mistake we see regularly is treating cold and dark as a fault because the screens remain blank after the battery is selected. On many aircraft, displays depend on a powered electrical bus, avionics master, generator, external source or APU rather than the battery switch alone.