X-Plane 12 Flight Model Report - X-Plane Developer

Very large post but interesting nonetheless!

I'm definitely looking forward to its release!!!

I CAN NOT TAKE THE WAITING ANYMORE, AUSTIN! STOP TORTURING ME!

This is the longest Austin rampage I've seen, sniff some glue if you can before reading this 🤣

Everything about this post is just amazing. Seems like x-plane 12 flight model is in a very different league. I wonder how time consuming it was for aircraft authors to tune their flight model using cheats and how much time the new one might save.

Wow! Amazing!

Is there a TL;DR ? 😛

Even when I'm just reading something Austin wrote I find I automatically read it in his ambitious voice. This is amazing. I hope his plans work out well.

2 hours ago, anden145 said:

Wow! Amazing!

Is there a TL;DR ? 😛

Austin disproved that XP12 is a mere XP11.6 as Laminar apparently almost completely rewrote the simulator. It's going to be easier than ever to attain POH aircraft performance without having to resort to dirty tricks. And weather will now pose the challenge it's supposed to be for pilots.

Wow, for anyone with doubts about how GREAT ! XP12 is I think that taking some good time to read this rather long "essay" by Austin will prove really important !

I am 100% sure Xp12 will be a success !

Edited June 2, 20224 yr by jcomm

I can't wait for this! 

Very long to read, but full of interesting info. I think the improvements in FM definitely surpass my expectations.

XP12 flight model will be a BENCHMARK for general purpose flight sims!

 

Here's a summary:

.Everything in XP12 has been overhauled and rewritten to be physics-based (flight model, weather, lighting, etc.), so that everything appears more realistic and each part is consistent with any other part;

.The "artifical damping" sliders are gone, because the flight model is now so good that they aren't needed anymore;

.The weather system is brand new. There are 3D clouds of various types (cirrus, stratus, cumulus, cumulonimbus) which change in space and time (so the weather pattern is dynamic). The weather conditions also have an influence on the ground (puddles, braking action, etc.);

.Real weather is using worldwide NOAA GRIB data to depict detailed weather at large scales, and it interpolates METAR data from each airport to seamlessly integrate it with the large scale weather;

.The interpolation is also made in time with weather updates, so no more sudden weather shifts, but smooth transitions;

.Improved thermal model, with thermals surrounded by a disk of descending air and rising up to cloud tops; thermals are also present in real weather, depending on weather conditions and time of day;

.Improved wake turbulence modeling, influenced by g-load of the aircraft producing it;

.Microburts modeling;

.(Apparently) modeling of density altitude with temperature deviations from ISA;

.Max number of engines increased from 8 to 16 (e.g. for multi-prop VTOLs);

.Airfoils per wings increased from 2 to 3 (tip, mid, root);

.Reynolds number are now tied to the specific airfoil (in airfoil maker), so you can model different Reynolds number in a single airfoil;

.Improved transonic modeling for swept wings;

.Improved Oswald efficiency calculation (for induced drag);

.Improved induced drag calculation for all wings, including propellers;

.Improved modeling of delta wings characteristics (based on data and experience of an F4 instructor);

.Improved downwash effect (wing downwash over stabilizer);

.Also, improved downwash, drag and lift variations in ground effect; 

.Improved flaps modeling; now the deflection of flaps decreases the stall AoA (it also applies to ailerons on a stalled wing);

.Improvement in lift and side force of bodies (e.g. fuselage);

.Revised and improved modeling of trim; now there are 3 types of trims available (aerodynamic, spring-loaded, moving stabilizer) for each trimmable surface;

.General improvements to helicopter flight dynamics, and simulation of blade slap;

.Updated governor types for helicopters (no governor, correlator, piston governor, turbine governor);

.Much improved seaplanes dynamics, in cooperation with professional seaplane operators for seaplane training;

.Simulation of "plowing" and running "on the step" during taxiing and take-off of seaplanes;

.Tire pressure for tires can now be set in Plane-Maker;

.The contact patch of a tire is spread out according to tire size; this allows realistic operation of bush-planes (tundra tires);

.Brakes now account for the total energy dissipated (depending on the mass and the speed of the aircraft); if you ride the brakes or if they've already dissipated the max possible energy (e.g. after a high-speed brake) they will overheat and suffer brake fade;

.Improvement in icing modeling; the ice now reduces the stall AoA, in addition to increasing drag;

.Many improvements to the modeling of jet engines; they can now be made extremely accurate in their operating parameters, including start-up and shutting-down times, acceleration rates, windmilling; he used data from B737 (CFM56) and from T38 flight tests;

.Now the entrainment of air due to jet wash is simulated; that can affect flying surfaces close to the axis of jet exhaust;

.Improvements in propwash modeling;

.Improved modeling of transmission losses; losses are now dependent on transmitted torque;

.Improvement in weight and balance: now loading stations can be added in Plane-Maker, and each of them contributes to the moments of inertia of the aircraft;

.Improvement in wing flex; fuel in wing tanks will cause wing-droop on ground;

.Pipes can now be used as sling-loads; this is to model the slung chainsaw used by helicopters to trim trees near power lines, and train their pilots;

.Improved Airbus Flight Control Laws, based on feedback from real pilots;

.Improved yaw damper;

.C172 is able to spin at aft cg;

 

.Available aircraft:

Piper Cub

Aerolite 103

R22 + seaplane variant

Austin's Lancair Evolution

F14 Tomcat

Cirrus SR-22

Cessna Citation-X

Airbus A330;

 

All those improvements are also making to the mobile XP version; he is convinced that the desktop and mobile versions will converge in the future.

 

Edited June 3, 20224 yr by Murmur

On 6/2/2022 at 2:04 PM, jcomm said:

Wow, for anyone with doubts about how GREAT ! XP12 is I think that taking some good time to read this rather long "essay" by Austin will prove really important !

I am 100% sure Xp12 will be a success !

I am sure you are looking forward to gliding in those new thermals! Are there any good third party gliders? 

On 6/2/2022 at 4:08 PM, Murmur said:

Very long to read, but full of interesting info. I think the improvements in FM definitely surpass my expectations.

XP12 flight model will be a BENCHMARK for general purpose flight sims!

 

Absolutely bonkers! I do not think anybody was expecting this many improvements! 

8 hours ago, strider1 said:

I am sure you are looking forward to gliding in those new thermals! Are there any good third party gliders? 

Well, there's honestly in X-Plane 11 ( or the competition for truth sake ) no glider that satisfies me in as far as flight dynamics and peerformance goes... But !  Austin has mentioned some of the FM new features / improvements that might really help creating a much more realistic experience.

So far the Go-To sim for soaring is still Condorsoaring, with SilentWings also very satisfactory although rather outdated.

Edited June 4, 20224 yr by jcomm

I'm also looking forward to these new thermals system.

In XP11 I did some flights with gliders over nice-looking areas like OrbX TrueEarth and such already, but my favorite areas were not available with nice orthos. In MSFS I can glide anywhere with good visuals, but the thermals seem very basic for the moment..

If XP12 brings in a "smarter" thermal system and if it's coupled with these better clouds, this should drastically improve the experience. The problem to get good ortho remains, though 😕

35 minutes ago, Daube said:

I'm also looking forward to these new thermals system.

In XP11 I did some flights with gliders over nice-looking areas like OrbX TrueEarth and such already, but my favorite areas were not available with nice orthos. In MSFS I can glide anywhere with good visuals, but the thermals seem very basic for the moment..

If XP12 brings in a "smarter" thermal system and if it's coupled with these better clouds, this should drastically improve the experience. The problem to get good ortho remains, though 😕

Both LR an ASOBO are investing on weather, and particularly on particular soaring weather, so we glider pilots can only try to benefit from both, while Condorsoaring v2 has also been announced 😁

ASOBO's approach to convection appears to be more detailled, using their rich satellite source data to compute the sources of thermal radiation, an approach followed in 2007 by Silent Wings and rather innovative at that time. But then Austin mentioned that new thermal structure and the way he uses good weather cumulus to calculate thermal reach ( I'll try to talk to him about blue days after xp12 release 😀).

Flight model wise it looks to me that xp12 will be more sound / complex than MFS, so, let's see how gliders work there compsted to xp11 gliders...

Edited June 4, 20224 yr by jcomm