I have P-Factor but no torque or gyro effects

[Oracle427]

Some immediate observations of mine. I like the 172 model a lot so far, but I would like to figure out if something is wrong with my install or if there is a bug. I am running Acceleration and have checked the FAQ (realism sliders, no auto-rudder, etc.). The settings all appear to be the same for the A2A J-3 w/Accu-sim which I also have.

I am able to keep my feet off the rudder all through the takeoff roll and climbout at Vx. There is absolutely no torque effect being modeled at all in my install. The only time I need to use a little right rudder is to hold heading in slow flight at 40kias with full flaps.

I then proceeded with some rudder coordination drills by trying to hold the nose on a point without yawing while banking briskly to the left and right to 30 degrees and those felt pretty good to me. The adverse yaw is being modeled and I need to account for it.

Next I tried a falling leaf stall and found that I could keep my feet off the rudders and use aileron only to bank and and level off the airplane to 45 degrees and back. I do like the way the spin is modeled once I kicked it over into one using the rudder. Not sure if this is a FSX limitation, because it is deeply staled flight I'm playing around with here, I imagine this is beyond the scope of what A2A was trying to achieve.

I don't know if I should open a separate thread for this, but I also find that the nose will not come down after a full stick back, full stall landing with the plane loaded with two 170lb front passengers and 40 gals of fuel. The aircraft will remain with the nose in the air and will not come down even with some light braking. It will come down if I release some back pressure or if I keep the stick all the way back and the airplane has nearly come to a full stop. All this is with the engine at idle power and full flaps the entire time. The elevator seems to remain very effective when it should probably be stalled.

--

Otherwise, I am greatly enjoying the 172R. My cockpit fogged up when I started up cold and dark in rainy weather. Not having read the manual at all, I looked up over the glareshield, just as I would on the real 172 and saw the defroster vents were closed to I opened them up with my mouse!! Then I opened up the cabin air as well. Nice attention to detail.

I was finally able to do a forward slip to a landing!

The sounds affects are wonderful.

The sounds and function of the avionics are very realistic so far. I have to set the Baro pressure on the autopilot and altitude changes must be initiated properly. I also see that changing the Nav source reverts back to Roll mode.

This is wonderful and I wish a detailed tool to simulate procedures in the cockpit like this was around when I was a student.

[Scott - A2A]

Oracle,

We were not happy with the p-factor and torque were were seeing in the FM, so we turned it down as it was more natural to have less torque and p-factor than something that wasn't right. We are working on bringing these systems into Accu-Sim. A much nicer and more accurate torque, p-factor, and some slipstream effects coming. This is also coordinated with some new physics for the ball in the turn & balance indicator.

I am not sure the nose up with four passengers and baggage is wrong. I know in our Comanche, as soon as people are in the back seat, the nose is so high it's like a tail dragger.

Scott.

[Alec246]

Yes, I did a Slow Flight and it almost didn't ask for any rudder. A 160HP should definitely ask for some rudder to keep the heading. It just drops a little bit of the left wing. There's some issue with the Yaw tendencies on this C172. The C152 I fly with a 110HP has much more than this 160HP. I remember to have my legs tired after doing slow flights on the weak C152

[Alec246]

Oracle,

We were not happy with the p-factor and torque were were seeing in the FM, so we turned it down as it was more natural to have less torque and p-factor than something that wasn't right. We are working on bringing these systems into Accu-Sim. A much nicer and more accurate torque, p-factor, and some slipstream effects coming. This is also coordinated with some new physics for the ball in the turn & balance indicator.

I am not sure the nose up with four passengers and baggage is wrong. I know in our Comanche, as soon as people are in the back seat, the nose is so high it's like a tail dragger.

Scott.

Is there a estimate for when this gets implemented? Weeks? Months? If I knew of this, honestly, I maybe would've waited to make the purchase. But the rest of the airplane is great.

[Scott - A2A]

Alec,

I am resistant to give a date because there are always unexpected events that can push things back. But this is a high priority for us and we already have the framework in place. It just needs a good bit of testing.

Scott.

[Oracle427]

I only had 2 passengers aboard which were my virtual self and the right seater both at 170 lbs. With 4 passengers I would certainly expect the aircraft to feel a little more "tail heavy" but given the CG remains well forward of the main gear when within limits, I would expect the nose to come down fairly quickly after touching down in a full stall with the engine at idle power.

Thank you and I do hope you can work with the engine to get the desired results sooner than later!

[Scott - A2A]

I would expect the nose to come down fairly quickly after touching down in a full stall with the engine at idle power.

The nose is a strut, and this isn't a strut like a car. I have to do chiropractic moves on our Comanche all the time to just keep the wings level.

There is likely going to be a large difference in the plane's stance with 4 people. However, next time we're up, we'll see if we can do some measurements with a gross weight loadout. I added this to our list of things to test on our next flight.

Scott.

[Alec246]

Alec,

I am resistant to give a date because there are always unexpected events that can push things back. But this is a high priority for us and we already have the framework in place. It just needs a good bit of testing.

Scott.

Thank you.

Most of all, I respect A2A's attitude of trying to fix the Torque that has always been flawed in FSX! Hope you guys succeed! This will bring this simulation to a level even more realistic!

If you need anyone to help with the testing, I have some C152 time. Not the same, but hey! A Cessna is a Cessna

Now back to FSX! Have to keep a look on that engine, with AccuSim anything can happen!

About the Nose high. The C152 with 2 people on board can keep the nose high until you're incredibly slow. My CFI did that once! Don't know about the C172 though

[Oracle427]

Scott - A2A"]

I would expect the nose to come down fairly quickly after touching down in a full stall with the engine at idle power.

The nose is a strut, and this isn't a strut like a car. I have to do chiropractic moves on our Comanche all the time to just keep the wings level.
Scott.[/quote]

Scott,

I see confusion about what I am trying to describe. Try to picture the aircraft remaining in a soft field takeoff attitude after touchdown with the tail very low and the nosewheel clear off the ground. This is the attitude I expect to touch down in once I have pulled the stick all the way back in the flare. The runway can not be seen over the nose and the nose wheel is not touching the ground. The problem I have is that while I hold the stick back the nose will not come down until the airplane has nearly come to a complete stop. I just tried this with only a pilot in the airplane.

I guess the simplest way to phrase it is that I am able to hold a soft field landing attitude for way too long after touching down in a full stall and with no throttle. Hopefully that makes it clearer?

I am seeing an expected ground attitude once the airplane pitches forward and the nosewheel makes contact with the runway.

A RL example is this video: http://www.youtube.com/watch?v=Uwy29IfglWY

If you listen at 1:05 the throttle is closed and the nose comes down right away, which is just how I experience it IRL.

The soft field takeoff is fun to perform in the A2A 172, but the nose refuses to come up until you have reached around 40KIAS after which the rest of the soft field takeoff behaves perfectly. It is funny to me because this is how I expect it to behave during landing. If the two behaviors could be swapped it would be perfect!

[flapsdown]

Oracle,

We were not happy with the p-factor and torque were were seeing in the FM, so we turned it down as it was more natural to have less torque and p-factor than something that wasn't right. We are working on bringing these systems into Accu-Sim. A much nicer and more accurate torque, p-factor, and some slipstream effects coming. This is also coordinated with some new physics for the ball in the turn & balance indicator.

I am not sure the nose up with four passengers and baggage is wrong. I know in our Comanche, as soon as people are in the back seat, the nose is so high it's like a tail dragger.

Scott.

Guess I am the odd duck here yet again , as I have noticed a big tendency for the plane to roll left, which I initially attributed to the torque from high rpm operations, but it seems like no matter how much I back off the power, I can't get a wings level flight without holding some "right-stick" - and I have checked all my hardware calibrations, realism settings and gone back to other planes just to make sure, and I do not experience this in other aircraft - is there some other type of test I can try?

Thanks,

Chris B.
aka "Flapsdown"

[sioux565]

Oracle,

We were not happy with the p-factor and torque were were seeing in the FM, so we turned it down as it was more natural to have less torque and p-factor than something that wasn't right. We are working on bringing these systems into Accu-Sim. A much nicer and more accurate torque, p-factor, and some slipstream effects coming. This is also coordinated with some new physics for the ball in the turn & balance indicator.

I am not sure the nose up with four passengers and baggage is wrong. I know in our Comanche, as soon as people are in the back seat, the nose is so high it's like a tail dragger.

Scott.

Guess I am the odd duck here yet again , as I have noticed a big tendency for the plane to roll left, which I initially attributed to the torque from high rpm operations, but it seems like no matter how much I back off the power, I can't get a wings level flight without holding some "right-stick" - and I have checked all my hardware calibrations, realism settings and gone back to other planes just to make sure, and I do not experience this in other aircraft - is there some other type of test I can try?

Thanks,

Chris B.
aka "Flapsdown"

Chris,

What is your passenger load like? If only the pilot is loaded, then I can see why you would be rolling left.

Sent from my XT901 using Tapatalk 4

[flapsdown]

Oracle,

We were not happy with the p-factor and torque were were seeing in the FM, so we turned it down as it was more natural to have less torque and p-factor than something that wasn't right. We are working on bringing these systems into Accu-Sim. A much nicer and more accurate torque, p-factor, and some slipstream effects coming. This is also coordinated with some new physics for the ball in the turn & balance indicator.

I am not sure the nose up with four passengers and baggage is wrong. I know in our Comanche, as soon as people are in the back seat, the nose is so high it's like a tail dragger.

Scott.

Guess I am the odd duck here yet again , as I have noticed a big tendency for the plane to roll left, which I initially attributed to the torque from high rpm operations, but it seems like no matter how much I back off the power, I can't get a wings level flight without holding some "right-stick" - and I have checked all my hardware calibrations, realism settings and gone back to other planes just to make sure, and I do not experience this in other aircraft - is there some other type of test I can try?

Thanks,

Chris B.
aka "Flapsdown"

Chris,

What is your passenger load like? If only the pilot is loaded, then I can see why you would be rolling left.

Sent from my XT901 using Tapatalk 4

Ha! I bet you are spot on (man do I feel stupid), for the sake of realism I put in my actual 250 pound self, and nobody else!
I need to keep reminding myself how well the physics are modeled in this plane...

Thanks for the feedback!

[jcomm]

Well,

I believe it is doomed to be limited by FSX's own limitations, and not A2A's fault... I look forward for what Scott mentioned, but I believe that such an Accusim "intervention" will require running the FDM externally (?) FSX simply does not cope with any spiraling slipstream effects, etc..., although it does a good job at simulating the RW attenuation the roll due to torque effects with dynamic pressure...
As a ( disappointed so far ) X-Plane 10 user, I should add that that simulator doesn't do it any better when it comes to prop effrects, and other important ( for me ) aspects of a flight simulator, partly the reason why I came back running to P3D, now FSX, and re-installed only my best aircraft (which include all of A2A's models I bought for it ). It's not perfect the way it is done in FSX, but still better than what I have in X-Plane after all...

In the meanwhile, and although this might not be a good idea because it might interfere with the A2A's performance tuning, I can only suggest that users who want to try it, play around with these parameters in the [flight_tuning] section of the AIRCRAFT.CFG, always backing up the original...

- prop_on_roll

- p_factor_on_yaw

- high_alpha_on_yaw

- high_alpha_on_roll

They are by default set at 1.0 on most aircraft, but I don't know how they're set in the A2A C172 yet! I usually reduce substantially any roll effects, because torque effects on most prop aircraft are only a factor at low speed / high AoA, and increase the high_alpha_on_yaw and p_factor_on_yaw because, since FSX does not take into account spiraling slipstream effects, p-factor has to be used instead (not realistic, but the closer we can get...)

Start with prop_on_roll=0.05, p_factor_on_yaw=1.8, high_alpha_on_yaw=1.8...

P.S.: Thinking about it... this is silly of me to suggest, because OF COURSE A2A surely has weighted all of the possible combinations of such parameters, and if they left it as they are, that's most certainly because it is so far the best compromise... nonetheless, we can always experiment

[Jigsaw]

Ha! I bet you are spot on (man do I feel stupid), for the sake of realism I put in my actual 250 pound self, and nobody else!
I need to keep reminding myself how well the physics are modeled in this plane...

Even though there don't seem to be any aileron trim controls in the actual cockpit you can still use aileron trim to keep the aircraft level if you assign the aileron trim controls in the control settings of FSX. That might be cheating, but when you only have a flightstick instead of a yoke that's very handy to keep the aircraft level while letting go of the stick to fiddle around in the cockpit with the mouse, without having to switch on the autopilot.

[Alec246]

This bird right now is IFR certified only on my FSX, flying with AP on after takeoff until landing. Really, no joy at all hand flying it at the current state