Larry, all the best for your recovery! You must have had a guardian angel - with a motorbike against a deer - the consequences could have been much worse!Wolfgang

Not quite a Cessna 172The single engined fighter planes for WW2 were basically engines with wings (and canon). All single engine fighter planes were made with assymetric wings tocounter the yaw in normal cruise flight - ie the wings were a different shape.Any speed not at cruise resulted in yaw.The later versions of the spitfire and sea-fury had to take at half power asthe yaw was too large to control with the flight surfaces at non-attack speedWhen taking off from carriers the single engine planes had to revto takeoff power before releasing the brakes or the gyroscopic change on power shiftwould flip the plane over. When landing - you must hold the same power untillanded or changes in yaw would make things "difficult".Ie all single engine planes (propeller) suffer from yaw. So does FSX parametric model this - yes, does it model it well on the default Cessna - its ok. Are other flight models for the cessna better - a bit. Do you want to get this perfect : fly a plane...helicopters suffer much more badlyFS9 yaw model was OK when at realistic settingFSX yaw model was turned down so it is not realistichovercontrol provide an addon that improves the flight dynamics considerably.Maybe you should check the calibration of the your joy-stick/rudder controls,maybe they don't allow full rudder deflection.

Before I changed the air file and the aircraft.cfg the default C172 (as all the other default single props) made an almost 90 degree turn to the left while accelerating down the runway. I do not think this was a calibration issue of my Saitek rudder padels, because all the add on single props I own behave just fine. @SurgoSince I do not own the Flight1 C172 I cannot judge how it's flight dynamics compare with Alexander's.Wolfgang

Before I changed the air file and the aircraft.cfg the default C172 (as all the other default single props) made an almost 90 degree turn to the left while accelerating down the runway. I do not think this was a calibration issue of my Saitek rudder padels, because all the add on single props I own behave just fine. @SurgoSince I do not own the Flight1 C172 I cannot judge how it's flight dynamics compare with Alexander's.Wolfgang

If you initiate a takeoff roll in a real C172, with no rudder input.. you'll be off the runway very quickly. The only thing that will keep it from becoming a 90 degree turn is the impending ground-loop :( I've done quite a bit of flight-modeling.. and own several payware singles.. haven't noticed much of difference between them and defaults when it comes to rudder use. The only thing I can think of for the discrepancy; is that MSFS doesn't model nose-wheels very well. A real C172 has an elastic linkage for the nose-wheel, so that you don't snap the nose-gear when landing with lotsa rudder input... so on a takeoff, once you reach a speed where the rudder is effective, the nose-wheel's turning power is lessened quite a bit. Perhaps some of the payware have a larger nose-wheel turning deflection, or it's placement relative to the main-gear is different (defined in contact points), meaning much less rudder input is needed during a takeoff roll ?I've never paid much attention to steering deflection when building (or tuning) a model.. mainly because I just "fly" a model without giving conscious thought to how much rudder I'm using. I will however, pay a lot of attention to in-flight rudder-use, and aim for realistic deflection needed for smooth turns, and trying for as close to a realistic slip as MSFS will allow.. and that always yields pretty realistic takeoff/rudder realtionships.In other words.. if a payware model of a light single needs LESS rudder use during takeoff than a default light single.. I'd say that the payware model is less realistic in that regard.