Engines

Let's take a look at the aircraft engines that make the aircraft fly. The A320 uses what is called High Bypass Ratio Turbofan Engines.

The basics first: if you are not familiar with how such an engine works, I really recommend you to spend 3 minutes watching the following video.

This excellent video is from CFM International which is one of the 3 manufacturers of engines for the A320. The other 2 manufacturers are International Aero Engines (IAE) and Pratt & Whitney (P&W).

On the A320 (and by extension on the whole Airbus family) you have two generations of engines. Airbus embarked on a modernisation program to make its airplanes more efficient and less fuel consuming. Apart from design changes on the aircraft itself (cf winglets) this introduced the use of new and better engines, referred to as the "A320Neo" which stands for "New Engine Option". These are gradually replacing the first generation airplanes that are referred to as A320Ceo, where "Ceo" stands for "Current Engine Option".

If you are still following, 3 manufacturers are 2 generations, that makes already 6 combinations. Add to this that each engine comes in different types. The engine type is linked to what is known as the engine thrust rating. Basically each family of engines is produces in different flavours that each have a specific thrust (referenced to as the maximum TakeOff thrust at sea level).

Pulling all this together, Airbus has devised the following naming convention: A320-XYZ

X is the aircraft version (cf 100, 200 family, ect). 

Y is the Engine Manufacturer:

• 0 General Electric-Aviation
• 1 (CEO), 5 (NEO) CFM International (Snecma and GE-Aviation)
• 2 (CEO), 7 (NEO) Pratt & Whitney
• 3 IAE (Pratt & Whitney, Rolls-Royce, Aero Engines Corp., and MTU Aero Engines)
• 4 Rolls-Royce
• 6 Engine Alliance (GE-Aviation and Pratt & Whitney)

Z is the Engine Type.

Now lets come to what we are developing as an A320Sim. As you can read in the Specification page of our Sim, we are implementing the Airbus A320 200 family. For this family the following engine manufacturers/types exist:

As you can see from the marketshare split posted by Leeham, the CFM and IAE are the most popular and most sold engines for the A320.

So, why all of this introduction?

Until a few months back, the engine modelling in my A320Sim SW was very basic and rudimentary. I only had one, and "from a distance" it's performance somewhat resembled that of an CFM56.

For an A320Sim "As Real As It Gets", that was simply not good enough 🙂

So with the support of a person at the University of Aachen in Germany and another person at the University of Sofia in Bulgaria, I was able to implement and add detailed engine models to my A320Sim Software for the two most popular engine fittings for the A320Ceo, respectively the IAE V2527-A5 and the CFM56-5B4.

For both of these engines I can now accurately calculate the Force, Fuel Flow, EGT, N1, N2, etc. 

This work on engine modelling was one part missing in the puzzle. The other missing part in the puzzle was the implementation of the ARINC424 Navigation Database (about which you can read in an earlier blog) allowing to construct flight plans using the real world nav data..

Finalizing these two parts are fundamental steps to enable the FMGC to be developed in more detail, since the whole flight plan prediction depends on having accurate engine models with which you can predict engine performance during the different phases of flight, combined with detailed and accurate flight plans.

For now I will return my focus to the FMGC update. But if you have the knowledge and would be willing to support me in modelling also the NEO engines "As Real As It Gets", then you can always contact me via the Chat 🙂