REP 3.3.0: new big bore engine model for X-Plane

A new update of the Reality Expansion Pack for X-Plane has been released with new features and improvements, especially to the engine.

This update is free for all the current REP users. If you don’t have a copy of it already, you can get it from the store.

New 100% custom engine model

The main new feature of this release? A new piston engine algorithm for big bores such the IO-520 and the IO-550 that will greatly improve your experience.

X-Plane 11.02 introduced a bug that, in some occasions, prevented REP to set the proper engine power output. This bug was the cause of errors in cruise speeds, fuel flows, CHT, oil temperatures and, generally speaking, engine dynamics.

Luckily, Laminar provided a new way to override the engine model with XP11.10. We digged into it and took the chance to rewrite our code to make it better than before.

Our engine code does not depend anymore on Laminar  piston engine model of X-Plane. That is, it is a fully custom engine model that do not rely on internal X-Plane dynamics.

Therefore, all the algorithms in the big bore engines are custom. They provide great precision in EGT curves, fuel flows, CHTs and – more important – power output!

Many of you noted that in X-Plane, the Manifold Pressure at full throttle is always too high or too low than expected. Eventually, our engine model gets rid of this problem. You will get the proper Manifold Pressure when at full throttle.

Another great thing introduced by this model is a more precise ROP/LOP dynamic. We wrote about Lean of Peak and Rich of Peak operations in this post. I suggest you to read it if you missed it as this is a very relevant topic.

This is a starting point for this new engine algorithm. From here, we plan to improve it with future versions of REP.

Beware, this new engine model does not kick-in with the C172SP IO-360! The Lycoming IO-360 model is already good and does not suffer from the bug stated above.

Engine monitor and Red Box

Speaking of mixture leaning, this new release introduces a simple but useful engine monitor. You can enable it from REP’s settings window. Once enabled, it will show informations such Manifold Pressure, RPMs, Fuel Flow, EGT (difference from peak included) and power output. It will be shown only over the 50% of power, so it won’t bother you during ground operations, and only for a while when you change engine settings.

The engine monitor let you to set your engine as required with great precision. It will help you stay away from the red box.

Being in the red box will not kill your engine but staying away from it will certainly extend its life!

To make things a little bit simplier, a new in-flight tip will let you know when you are operating in the red box.

Complete changelog

• New! C210, F33, V35, B58: New custom engine model
• New! C210, F33, V35, B58: New engine monitor (enable it from REP’s settings window)
• New! All aircrafts: In the walkaround oil system check, the oil progress bar is now decorated with oil quantity notches
• New! C172: The installer now supports the new incoming mod for the GTN 750 by BourrinoPathe
• New! Walkaround keyboard/joystick commands (use them in VR!)
• All aircrafts: fixed the engine RPM surge during magnetos check
• B58, F33, V35, C210: Improved drag models in XP11
• All aircrafts: Improved ground roll sounds
• All aircrafts: more efficient state loading
• Dropped support for 32 bit builds
• Minor fixes