Left turn tendency on ground roll extreme normal or not, cessna 152/jpl, some others

I was trying to find a video on this to clarify things but cant seem to find examples.

If you apply full power and dont then do immediate right rudder, the plane tends to veer extreme left, not just a little.. im not sure if thats normal or an issue somewhere else.

I know about the turning tendency /pfactor but this seems extreme, i should upload an example. Using my mfg crosswind pedals i have quite a bit of right rudder and its a struggle to keep on the center line sometimes. Not sure how this compares to real life

Anyone else have the same issue?

i agree the pfactor is very noticeable in the 152, but i think this is how it should be
if what you are seeing is indeed the pfactor, it should reduce significantly once you have some airspeed on the airframe, say 60kt or so

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Flying the WBSim/JPLogistics Cessna 152 right now and don’t have this issue. Just the typical need to apply some right rudder. What does the windsock look like?

it occurs even with no wind in my case

Not sure what the real life 152 should be like, hard to find a video showing no feet on the rudder at max power or the extreme pull before applying in real life

i uderstand that you are all good on your controls right? calibrated? dead zone set? all that is good?

Moved to User Support Hub User Support Hub > Aircraft & Systems that is more appropriate for community support.

I fly it a lot but just don’t really ‘notice’ it very much(I don’t recall it being something remember-able) and just adjust naturally. Heck I find the WACO easy peasy but had definitely adjusted the setup for it and it was NOT the case with low resolution TFRP’s I used to have. Maybe amp up the rudder pedal response a little bit for that particular aircraft/control setup? It really is a tiny aircraft about the empty weight of a big Harley Davidson with a huge increase in surface area. A 152 will hunt around in the wind quite a bit, including that from it’s own propeller.

Try another aircraft with the same controller setup like the Beaver and see if you’re chasing P-factor too. May have a disproportional aileron/elevator authority vs rudder in the setup.

There is a balance to aircraft, if you have a lot of aileron/elevator response in a yoke but not much in the rudder, it may seem like the rudder is ‘ineffective’. And it’s not something you can get by just setting everything the exactly same on the screen, it all needs to feel balanced out for a given airframe. If you have a crazy ‘strong’ rudder curve and mushy aileron/elevator axis, it can feel way off in ground handling too. Typically the mechanical multipliers for surface control wires/cables/tubes are all fairly similar. Of course the pedals themselves need to have decent resolution.

in my case yes, other aircraft, like jets for instance, it is pretty straight and visibly you can see the rudder external view centered.

It would be odd if there were a p-factor in a jet

yeah a jet would be odd, but point was the controls arent pulling

On a flat runway with no crosswind a jet will just go straight on acceleration. There’s no vortex of wind swirling around the fuselage hitting your tail on one side from a propeller.

What pedals are you using?

pedals wise, mfg crosswind, but they are centered, no issues there

i think you may be noticing just the way the model was designed
i noticed it too
in the 152 the left pull is strong
it is a very very light aircraft

Can’t say if this’ll help or not.
Sometimes it seems it blows out the calibration.
I’ll run it again and it’s fine for a random period of time.

which calibration or panel is this, in windows?

Aye, Keptin!

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I’d say I’ve experienced this issue as well. Lots of good points here with rudder being set appropriately to match curves of elevator and aileron, all good advice.

Even with all of that though, I think OP’s point remains as it is producible without any wind. I’ve never flown a jet in MSFS (i know..) so cant comment there, but with small light aircraft I DO notice what you describe. It is better or worse for some plans and I have even felt an update change this behaviour slightly (PC12 for example).

I think to get to the bottom of it we can turn on CFD Visualization to see if the p factor is indeed causing this. Depends if the plane uses it I suppose.

Are you talking about strictly the JPL 152? Have you tested this with some default aircraft? I suspect it may be a common technique that somehow could improve an aspect of the flight model, but have this as a consequence/side effect. That sort of practice shouldn’t be present in a default Aircraft (i hope).