Prop Reversers

[joncoughlin]

Landing timestamp is in the link. 

Any thoughts on why my props failed to go into reverse on this landing? It has happened to me in the past when I don't have my props at max RPM, but in this situation I'm sure I did have my RPM all the way forward. 

Is it possible for the reversers to fail to kick in if I move the power levers too fast? 

You can see on the controls diagram that the levers are in the Reverse zone, at least. 

 

[android772000]

For me I have noticed it can take a while for the props to get into reverse. When I land and bring the throttle to ground idle, then press the move lever to reverse thrust key, the props typically don't move into reverse until I've slowed to 50 or 60 knots. I assumed this was user error, or induced possibly by my throttle axis tune, but I'm unsure. When not moving they go into reverse thrust immediately, but after touchdown it takes like at least 5 full seconds. 

[joncoughlin]

48 minutes ago, android772000 said:

For me I have noticed it can take a while for the props to get into reverse. When I land and bring the throttle to ground idle, then press the move lever to reverse thrust key, the props typically don't move into reverse until I've slowed to 50 or 60 knots. I assumed this was user error, or induced possibly by my throttle axis tune, but I'm unsure. When not moving they go into reverse thrust immediately, but after touchdown it takes like at least 5 full seconds. 

I noticed that a lot. It doesn't fail for me every time, so I did some landing circuits to check. 

I'm this video the props reverse at high speed on landing one, then fail to reverse until low speed on subsequent passes. 

I assume there is something repeatable going on?

 

[tkyler]

3 hours ago, joncoughlin said:

Any thoughts on why my props failed to go into reverse on this landing

yes, a bug with X-Plane's TPE model for sure...they'll go into reverse eventually, but I've seen it take as long as 10 seconds, quite incorrect.  It has been filed and there is some type of fix in the next X-Plane update, which rumor has will be released in a few days; however, until I test it, I'm not sure what the behavior will be.  I had a short exchange with Philipp, the programmer of the TPE engine and given the limited exchange,  I can't say for sure he understood and/or agreed with how I suggested it be modeled, so I'm not sure what to expect.  The reverse should be darn near instantaneous with lever movement...this is due to the way the hydraulic circuit of the 'pitch sleeve' works.    I've been waiting on this fix for a bit....fingers crossed.  If not, I guarantee I'll be knocking on Laminar's door again.   

Philipp has actually done quite a good job of modeling this engine, it worked great in V11, but I believe he added a few more accurate features like NTS lockout etc. and somewhere in the last few patches, reverse in the TPE implementation got broke.   I used to custom model this stuff myself, but I've known Philipp for a good many years and he's extremely capable and as Laminar adds more accurate engine behaviors, then the more custom behaviors I have to 'pull out' of my plugin code so they don't clash, but in doing so, I defer to their implementation in some areas.   Now having worked with these guys in years past though, they're quite agreeable to suggestions and improvements and I fully expect we'll get this one ironed out.....and I do hope its in this next update from X-Plane. 

-tkyler

Edited June 7, 2023 by tkyler

[joncoughlin]

19 minutes ago, tkyler said:

yes, a bug with X-Plane's TPE model for sure...they'll go into reverse eventually, but I've seen it take as long as 10 seconds, quite incorrect.  It has been filed and there is some type of fix in the next X-Plane update, which rumor has will be released in a few days; however, until I test it, I'm not sure what the behavior will be.  I had a short exchange with Philipp, the programmer of the TPE engine and given the limited exchange,  I can't say for sure he understood and/or agreed with how I suggested it be modeled, so I'm not sure what to expect.  The reverse should be darn near instantaneous with lever movement...this is due to the way the hydraulic circuit of the 'pitch sleeve' works.    I've been waiting on this fix for a bit....fingers crossed.  If not, I guarantee I'll be knocking on Laminar's door again.   

Philipp has actually done quite a good job of modeling this engine, it worked great in V11, but I believe he added a few more accurate features like NTS lockout etc. and somewhere in the last few patches, reverse in the TPE implementation got broke.   I used to custom model this stuff myself, but I've known Philipp for a good many years and he's extremely capable and as Laminar adds more accurate engine behaviors, then the more custom behaviors I have to 'pull out' of my plugin code so they don't clash, but in doing so, I defer to their implementation in some areas.   Now having worked with these guys in years past though, they're quite agreeable to suggestions and improvements and I fully expect we'll get this one ironed out.....and I do hope its in this next update from X-Plane. 

-tkyler

Thanks for all the detail! Interesting to hear it is an XP issue from 11 to 12. I'll have to look for it on other turboprops. 

[tkyler]

19 minutes ago, joncoughlin said:

I'll have to look for it on other turboprops. 

I don't think it was directly between V11 and V12...I think it got borked somewhere within the V12 run, in the last patch or two.  Also I'm not not sure its on the PT-6 model.     I think it could be as simple as Philipp's misunderstanding of the TPE BETA hydraulic circuits.  This isn't a knock on Philipp, he's tasked with a large number of areas of development within X-Plane and so he can't sit around reading TPE and Hartzell manuals for hours on end like I do....plus he has to also deal with the PT-6.    I print out section drawings and have to hand color the components and circuits to help me understand the design and behaviors....I mean, this stuff isn't always easy to interpret .

 

Edited June 7, 2023 by tkyler

[joncoughlin]

1 hour ago, tkyler said:

I don't think it was directly between V11 and V12...I think it got borked somewhere within the V12 run, in the last patch or two.  Also I'm not not sure its on the PT-6 model.     I think it could be as simple as Philipp's misunderstanding of the TPE BETA hydraulic circuits.  This isn't a knock on Philipp, he's tasked with a large number of areas of development within X-Plane and so he can't sit around reading TPE and Hartzell manuals for hours on end like I do....plus he has to also deal with the PT-6.    I print out section drawings and have to hand color the components and circuits to help me understand the design and behaviors....I mean, this stuff isn't always easy to interpret .

 

lol yikes! Having worked in aerospace and always shied away from valves and plumbing, I don't hold any grudges about it.

[tkyler]

Status report,

I just got my hands on V12.06....and the reverse seems only marginally better, still not right IMO.     I expect a back and forth with Laminar on this one...and hope we can see eye to eye.  If not, I'll have to overwrite and rewrite my own prop governor...not my first choice as it'll take a bit....*sigh

-tk

Edited June 9, 2023 by tkyler

[kdub]

On 6/9/2023 at 9:54 AM, tkyler said:

Status report,

I just got my hands on V12.06....and the reverse seems only marginally better, still not right IMO.     I expect a back and forth with Laminar on this one...and hope we can see eye to eye.  If not, I'll have to overwrite and rewrite my own prop governor...not my first choice as it'll take a bit....*sigh

-tk

I just returned to the MU-2 after many months.  On my first approach into KRNT I was hot crossing the threshold( about 112 knots).  7 knot crosswind to boot.  Got her down and stopped with plenty of room to spare.  Reverse works well for me.  The Moo is a really nice bird, overall.

[Mike710]

Hi,

I just bought the Moo, and started to learn how she flows, so sorry It this has been asked before. I can´t seem to get the reverse to work properly. I am not even sure I have the right keybinding.  I binded the Lift dual throttle engine as per the manual, although I could not find the key stated on the manual (xscenery/mu2b60/lift_power_levers_DP). But as much as I tried, I only got It to work on the ground once and that´s It.

Can someone please let me know which Is the correct keybinding and If there´s a particular process that you have to go through In order for It to work/trigger?  Even If It doesn´t work properly yet, for the reasons stated above (post), I am still Interested In knowing the whole process and the right keybinding.

BTW, I am using a TM Warthog HOTAS and both throttles are linked (latched), I have also set both throttles to 3 and 4 as stated In the manual.  I also have the Auto-Stop Power Levers checked In the Moo Gizmo settings. Using X-Plane 12 latest version as of date.

Thank you

Edited April 7 by Mike710

[Mike710]

23 hours ago, Mike710 said:

Hi,

I just bought the Moo, and started to learn how she flows, so sorry It this has been asked before. I can´t seem to get the reverse to work properly. I am not even sure I have the right keybinding.  I binded the Lift dual throttle engine as per the manual, although I could not find the key stated on the manual (xscenery/mu2b60/lift_power_levers_DP). But as much as I tried, I only got It to work on the ground once and that´s It.

Can someone please let me know which Is the correct keybinding and If there´s a particular process that you have to go through In order for It to work/trigger?  Even If It doesn´t work properly yet, for the reasons stated above (post), I am still Interested In knowing the whole process and the right keybinding.

BTW, I am using a TM Warthog HOTAS and both throttles are linked (latched), I have also set both throttles to 3 and 4 as stated In the manual.  I also have the Auto-Stop Power Levers checked In the Moo Gizmo settings. Using X-Plane 12 latest version as of date.

Thank you

Ok I seem to have this working now...