Prop torque and P-factor on bonanza and baron
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Hi and first off all congratulations on those new releases.
I just bought the bonanza and baron package (already own the caravan and kingair which I really like) and something felt strange regarding the flight model.
I'll talk about the Bonanza for simplicity's sake.
What surprised me is that it seems there is no asymetric thrust AT ALL.
I ran several tests with the follwing conditions to make sure:
*No wind
*All other mods removed from community folder (apart from some sceneries and other blacksquare aircraft)
*I double checked flight model is set to modern and no rudder assistance (well, no asssistance at all).I can release the brake, apply full power, and the aircraft is right on centerline, not a single movement.
And i know it can sometimes be tricky in FS2020 to maintain centerline (although the most frequent cause seems to be tyre friction which is too low, coupled with a somewhat exxagerated effet of crosswind on the vertical stab) so I was all the more surprised.
Then, when airborne, I can cut and slam the throttle from idle to full power several times and the ball remains centered, which really seems strange.I have no experience in real life on a bonanza, but as a single prop with a rather powerful engine, I expected it to demonstrate more of those effects. (IRL I only flew single engine prop with up to 200hp).
So my question is: is what I am experiencing normal or am I missing something ?
best regards.
Charles
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On my installation the bonanza tracks straight down the runway until reaching about 40 knots then pulls to the left quickly leaving the runway if rudder correction is not used. Is yours different from this?
It is true some other airplanes like the 172 or the new PA28R pull left due to P-factor at lower ground speed.
And I agree flying the Bonanza there is not much induced yaw when changing prop RPM in flight, for example starting a decent. PA28R has more response to RPM change.
As a data point I compared the propeller config items between Black Square 'mod' and the earlier Bonanza improvement project mod published last year. Black Square appears to have incorporated the learnings from that project. The values are very close including the modern Prop config values. BlkSqr offers a significant upgrade to prop model from Asobo original.
In short, the Bonanza with this mod is somewhat less responsive to P-factor than other advanced aircraft models. But is it a bug? Opinions?
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@jbbz I just tested again and I confirm I have NO left pull at 40kt. Are you sure there was no crosswind at all when you ran your tests ? Because it looks like the effect of the crosswind on the tail coupled with tyre friction being too low.
Nevertheless thanks for your input. -
@meh1951 I am understanding you better now. With 1 knot crosswind from the left it turns left at 40 knots. With 1 knot crosswind from the right it turns right at 40. With zero wind it tracks the centerline up to 100 or beyond without rudder input.
By comparison the PA28R aircraft are extremely twitchy requiring a lot of right rudder at any speed over slowest taxi. The turning moment is much greater than that any from cross wind.
This Bonanza behavior (no P-factor) does seem an issue that should be reported.
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@tango4 My observations were concerning the Bonanza. Reviewing the Baron, in my tests the Baron model acts as expected during the takeoff roll. The yaw due to asymmetric thrust is certainly present when engines are not equal in output. But once in flight, I suggest the modeling of P-factor left-turning moment with both engines at high power is less that what I would expect. I also note that the Black Square team has not done much to improve the propeller model beyond Asobo original. Unlike the Bonanza, the new propeller physics model is not implemented for Baron.
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@voice-of-reason thanks a lot, I did not know if someone from Just Flight or the dev himself had seen this post. It was clearly not meant to rush you in any way.