The Engine’s Logic

The Reality Expansion Pack features the most complex piston engine logic ever experienced in X‑Plane. It is 100% custom. It does not rely on internal X-Plane dynamics and it completely overrides the default piston engine modeled in the sim.

This big improvement is available for all the aircraft targeted by REP.

Why? Because a custom logic works to simulate all the different components you find in a real engine.

The code inside REP recreates the behavior of the pistons, the cylinders, the oil, the fuel lines, the injectors, the battery, the cowl flaps, the spark plugs and all the other little things that make an engine alive.

The result is that you need to properly manage the engine. If you don’t, the engine will revolt against you, leaving you alone just when you need it more.

In fact, you have to follow the proper procedures to start it up, to warm it up and to fly it to the sky.

Just like the real thing, the engine wears out one flight after another. If you do not take care of it, such as replacing the oil when necessary, it will die on you one day or another.

The engine logic is enhanced with each upgrade. That is, with every upgrade you get more things to care about and more stuff to learn when in flight.

The Features

This is the list of things that REP is able to simulate within X-Plane:

  1. Proper procedures for pre-heating, priming, and startup
  2. Realistic engine spool-up and “roar” at startup
  3. Starter overheat and wear
  4. Turbo automatic waste gate (C210 only)
  5. Turbo lag (C210 only)
  6. Realistic engine torque
  7. Correct EGT behavior
  8. Perfectly matching power output (BHP) at every regime/setting
  9. LOP and ROP operations
  10. Spark plugs fouling
  11. Interchangeable spark plugs between default and fine-wire
  12. Correct cowl flaps drag
  13. Realistic engine vibrations (needs HeadShake)
  14. Cylinders compression
  15. Cylinders cracking and seizure caused by improper engine management, such as running at high RPMs when the CHT is still too low
  16. Propeller movements at low speed caused by the cylinders compression
  17. Fuel filter clogging
  18. Fuel vapor in the fuel lines that may prevent a startup
  19. The “popping” and “spitting” sounds of a big bore engine
  20. Oil viscosity at different temperatures
  21. Different oil types (SAE10W30, SAE30, SAE50) that can be replaced in the hangar
  22. Oil filter clogging
  23. Wearing of the oil fluid
  24. Oil pump failures
  25. Vacuum pumps failures
  26. Electric pre-heating
  27. Winterization kit

The Behavior

Did you know that X-Plane’s default piston engine is not as good as you may have thought when it comes to simulating a specific engine model? That is because it is designed to “just fit” every kind of airplane.

It means that it’s made out of compromises to be “good enough” under every operating condition. That is, it’s not “realistic enough” to be used to simulate a specific engine model.

This is where REP enters the game.

Every engine simulated by REP is so realistic that it has its own behavior. Something that you won’t find in the default X-Plane engine.

REP’s engines can starve on fuel vapors or be flooded by the fuel itself if not managed correctly.

Every engine outputs the correct HP at every regime set. You will get the correct fuel consumption and thrust under any operating condition.

You have to correctly prime the engine before startup, depending on the temperature of the cylinders.

Did we mention that REP features an electrical engine pre-heater that helps you to start the engine in winter? And what would you say of the propeller animations? Check them out in the video below.