How many times have we waited in anticipation for the new simulation where advertisements boast claims of "ultra-realistic" flight-models that don't stand up under scrutiny? Fighter Squadron: Screaming Demons Over Europe is one of the most recent simulations to suffer the indignity of exagerrated claims.

Before you write off FSSD as a failure, however, all is not lost. In an unprecedented effort, Michael Harrison (Senior Software Engineer for Parsoft) has undertaken the daunting task of rebuilding the flight models of the complete list of shipped aircraft. To further exemplify his passion, he is doing this primarily on his own time. In the following article, I will pass along what I've since learned from Michael regarding what is missing, what is being done and how it will affect this simulation, as we know it.

What's the big deal about accurate flight models?

To many this is an obvious question with an even more obvious answer. But the truth is there are surprisingly quite a few first-time sim'ers, who simply echo what they hear online and in forums without fully understanding what they're hearing.

One of the most important aspects of ACM (air-combat maneuvering) is knowing the limitations of your aircraft and your opponent's aircraft. This knowledge dictates how you will engage, attack and defend yourself from your opponent. If a simulation's flight-model does not properly depict a given aircraft's performance accurately, you've effectively removed virtually all the strategy from the simulation. Doing this to a sim flight model is the equivalent of changing all the pieces of a chess game into queens, or playing the game without any rules.

What's really wrong with the FSSD flight-models?

Most of the complaints and observations from the flight-sim community focus primarily on the lack of proper departure from flight. In actuality, stalls in FS are already present; it's the repercussions of exiting the stall that are missing.

Currently when you do get into a stall situation you are welcomed with a soft and very manageable recovery. Other issues, such as lack of proper bleeding of speed during climbs or flat turns, were corrected by the release of the 1.5 patch in which the viscosity of the air was increased to better facilitate drag.

The reasoning for the flight departure problem is best answered by a paragraph I received from Michael Harrison. "The airfoil data that was generated had spikes in it (presumably to simulate the turbulence that is typical during stalls) and the lift did not drop off fast enough in the stall region. This meant that it was difficult to get into a true stall.

"Furthermore, the weight distribution on the planes was off, causing the "center of gravity" to be too far forward. This would aid the aircraft in stall recovery, which is unrealistic."

To simplify... the generated data that was manipulated to induce stalling did not have a long enough "occurrence" to allow the aircraft to lose enough lift to enter a proper stall condition. That coupled with the fact that the "center of gravity" was off, allowed the planes to automatically "nose-over", causing an overly easy stall recovery.

Fine … How to fix it?

To better answer that question, let's discuss Fighter Squadron's flight-model and how it works. Fighter Squadron's flight-model derives its data from a CFD program Parsoft licensed from NASA. With this program, airfoils (simple aerodynamic shapes that develop lift) are placed within a liquid-dynamic environment and fluid is run over the surfaces to determine their lift values. Tables of lift, drag and moment (with optional modifiers for leading and trailing edge devices) are used to parameterize each airfoil.

This data then is inserted into a specific airplane's LOD file, (a file that contains all the aircraft's specific data) which in turn provides us with the given flight-model, as we know it. Obviously once this raw data is obtained, much of it can be manipulated and "tweaked" to accurately match known aircraft specifications.

In case you are new to Fighter Squadron, all of the sims aircraft are made up of multiple objects. Each of these objects independently has lift, drag, moment, and damage values. It's the combination of these objects that make the aircraft and its flight model as a whole. In laymans terms … each individual object (pieces of the wing, fuselage, propeller) have specific flight data that contribute to the entire flight model of the aircraft. So when you shoot a portion of a wing off an aircraft, the flight-model is affected in a real and dynamic way.

Let's go back to Michael Harrison:

"All the known texture mapping problems have been fixed and I've been systematically going through all the airfoil files and fixing the curve data for lift, drag and moment so that they are as correct as they can be. Without a Cray, they won't be "perfect" but they will be quite a lot better than "good enough" for a PC simulation.

"I'm currently going through all the aircraft and adjusting the weight distribution so that it's all as correct as can be. (Which can be difficult at times. Just how much * does* the outer wing section weigh?) This particular modification is a tedious process that we didn't go through for the initial release version of Fighter Squadron, due mostly to time constraints and the fact that the aircraft flew fairly close to "correct" as they were. When facing a deadline, it's very difficult to get some people to understand that they may not be correct, just "good enough.

Cool … So how will the changes affect FS?

One of the obvious answers is that people will have to get used to planes stalling under certain conditions. No longer will the aircraft allow people to simply "yank and bank" without any real repercussions. Veterans should have little problem understanding and adapting to the changes. However, "newbies" will have the difficult tasks of learning how to keep the planes in the air.

A flyable B-17.

The "global" weight (the default weight) for an aircraft will remain the same. But when one of the accrued objects that make up the aircraft is removed (blown / broken off) … the new weight and inertia settings will more realistically affect the performance.

The instruments are legible even out here.

What and when?

The important thing to keep in mind is that Michael Harrison has undertaken this project on his own, to be completed largely on his own time. To compound the difficulty in this undertaking, he is also in the process of moving himself and his family to a new home.

As of our last discussion, the flight models were coming along nicely. He has been prepping the P-51 and the Fw-190 and should have those out shortly. Once those have had some limited testing, the rest should follow shortly afterward. Suffice it to say that because Michael is doing this on his own time, "real life" has precedence. Michael's best guess for an ETA on the whole plane set is, "when they are done".

It is my personal opinion that thanks to Michael Harrison's personal sacrifice and Parsoft's understanding Fighter Squadron will rise out of the ashes of condemned simulations like a newborn Phoenix. I expect it will easily meet the hyped expectations that had been initially set out.

Unofficial FM Patch

Don't want to wait? Download Etienne Labuschagne's Flight Model patch right now. This patch can be used with or without the 1.5 patch since it only affects the aircraft models themselves. Changes/Fixes:

1) All the aircrafts' wing loadings have been increased to be historically correct (as historically correct as my sources are!). Those who's wing loadings I could not get, was changed via and educated guess and some thumb sucking.

2) The Lanc, B17 and Me262 should not lose their engines anymore due to damage.

Download the official 1.5 patch: Fighter Squadron 1.5 660k.