October 16, 201510 yr http://forums.x-plane.org/index.php?showtopic=89958 Austin's post in the thread is here: http://forums.x-plane.org/index.php?showtopic=89958#entry958066 Sooooo, thx to Murmur, finally the "torque bug" was found Flying gliders since 1980 Flightsimming since 1992 AMD Ryzen 5600x, 32GB RAM, GPU Nvidia RTX 3060 Ti 8 GB, 1 TB and 500 GB nvme2 SSD drives, HP 27" 60Hz LED monitor @ 1920x1080, T16000, Hotas from old X52 Pro, Saitek Combat Rudder Pro (2010 model)
October 16, 201510 yr LOL! :smile: So the torque felt by propeller aircrafts is double what it should be. Austin said it should be fixed in 10.50. I wonder when was it introduced though? X-Plane 10? 9? 8? There also seems to be some other inaccuracies in the flight model, that could contribute to discrepancies in the response of the aircrafts, and that I hope to track and analyse thanks to a custom plugin I made. So hopefully they could be fixed in the future. "Society has become so fake that the truth actually bothers people".
October 16, 201510 yr Outstanding work Murmur, :Applause: Thanks! Windows 11 - Samsung 990 Pro M.2 | Asus Prime Z690 | i7 12700KF HT | DeepCool LS520 SE | MSI 5070 Ti Ventus OC | 64GB G.Skill XMP II | Lian Li 216 LANCOOL RGB | TrackIr v5 | Honeycomb Alfa - Bravo - Charlie | MSFS 2024 - Samsung 990 Pro M.2 | Curved 27" MSI | JBL Quantum 810
October 16, 201510 yr Author The torque bug started somewhere along version 9. I still remember it, and Austin announcing he had finally started to computer prop torque... Flying gliders since 1980 Flightsimming since 1992 AMD Ryzen 5600x, 32GB RAM, GPU Nvidia RTX 3060 Ti 8 GB, 1 TB and 500 GB nvme2 SSD drives, HP 27" 60Hz LED monitor @ 1920x1080, T16000, Hotas from old X52 Pro, Saitek Combat Rudder Pro (2010 model)
October 16, 201510 yr So, in the last few weeks you've given us improved clouds, improved fog, and found the torque bug ! Great work Murmur, thank you so much!
October 16, 201510 yr Commercial Member After reading through the linked post, that's some very impressive work there... good job! Jim Stewart Milviz Person.
October 17, 201510 yr Is this when the aircraft is pulling to the left? After takeoff.... No. The airplane should pull to the left on the takeoff run & initial climb. As airspeed builds the need for right rudder diminishes. X-Plane's torque problem has to do with the plane wanting to roll left. It also means constant roll corrections with power changes. In reality, there can be very noticeable torque, when the plane heads down the runway. The left wheel will push down. It's mostly noticeable when quickly adding power with slow airspeeds, such as go-arounds, or touch & goes. By the time we're to normal flying speed, the torque is overun by the wings lift. Some X-Planes give the impression that the pilot has to be holding the yoke to the right, so the airplane won't be rolling to the left on takeoff. It also gives the impression, that this torque force will even be more powerful with larger engines. In reality, we should be using right rudder on takeoff, and not holding the yoke or stick against a perceived roll from engine torque. It's a fact, that torque can completely roll an airplane over, when too much power is added to quickly, while the airplane is barely flying (low airspeed). This would often happen on WWII type aircraft carriers, during a wave off. P-51 Mustangs are also well known for it. But the P-51 takeoff, doesn't require aileron trim. It calls for right rudder trim, and a foot on the right rudder. Get up to airspeed in the correct manner, and the airplane won't want to roll to the left, as soon as you leave the ground. Even with the high powered P-51 engine, the torque is still overpowered with the wings lift. The spiral airstream will still call for right rudder, until airspeed is high enough to counter it with rudder trim, and/or an offset vertical stab. Without offset vertical stabs, or fixed/adjustable rudder trims, or offset engines, or a combination of all...................these airplanes will always yaw to the left, with a clockwise turning prop, from the cockpit view.
October 17, 201510 yr Author But beware that there is a LOT more behind the scenes.... Murmur has been working, using pure scientific method, to seek for other quirks... As he wrote in this thread, he has developed a set of scripts that runs a detailed evaluation of various aerodynamic parameters, and compares them to rw data, allowing to check how close a given aircraft model has those values in X-Plane. The torque bug may not be the only "problem". A prop aircraft, but any other aircraft as a mater of fact, is dependent on so many factors in terms of design and how it's aerodynamic properties characterize it's way of flying that it's difficult for a generic flight simulator to properly model any specific model accurately. Mumur's scripts will probably give the developers further insight into what has to be adjusted on a given model. To all I recommend reading the many interesting sources with a wealth of great information available, for instance, at the FlightLab's site, under "Download Courses". Read, at least, chapter 4 on Lateral and Directional stability, and understand, among other things, why aircraft, including prop aircraft, compensate for the torque effect itself, making it secondary, as dynamic pressure, slipstream effects, dihedral, weathervane stability and other factors become prevailing... Let's look fwd for whatever Murmur's finding about the "torque bug", and other aspects of X-Plane's FDM can bring developers for the future of the sim... We're getting there, slowly, but with sound steps! Flying gliders since 1980 Flightsimming since 1992 AMD Ryzen 5600x, 32GB RAM, GPU Nvidia RTX 3060 Ti 8 GB, 1 TB and 500 GB nvme2 SSD drives, HP 27" 60Hz LED monitor @ 1920x1080, T16000, Hotas from old X52 Pro, Saitek Combat Rudder Pro (2010 model)
October 17, 201510 yr Moderator Awesome work Murmur, have a virtual beer on me. I'm also quite amazed Austin responded to the post, it means they do actually read the forums in-spite of what many people actually say
October 17, 201510 yr I'm also quite amazed Austin responded to the post, it means they do actually read the forums in-spite of what many people actually say Keep in mind though, he has been informed via private emails on that thread, so I think they don't usually follow the forums. "Society has become so fake that the truth actually bothers people".
October 17, 201510 yr Thanks to Murmur, jcomm, and several others who have persisted in bringing this to the forefront. I also read (on Sesquashto's post) and found to be true that going into the airfoils folder in your main x-plane folder and clicking (at the top) the line saying something like bring to current standards, it will update all your aircraft to the latest 10.41 airfoil standards. It is said to greatly improve rotor-wing aircraft, but adjusts all the others as well. Great information coming from this community! John John Wingold
October 17, 201510 yr Moderator Either way, I'm glad somebody found and pointed this out, otherwise I think it would have been a long time before it was actually fixed :-)
Create an account or sign in to comment