Gents, the difficulty in taxiing with the C90B (as it was with the Aeroworx B200 and with nearly every MSFS turboprop) stems from the fact that the core MSFS turboprop engine code does not have any beta range. In a real PT6-powered aircraft, the part of the power lever travel between flight idle and reverse is called the beta range...and this is where the power levers directly control prop pitch without changing the engine N1. The result is much finer control for ground operations.

 

Next time you're taxiing the C90B, notice that as soon as you move the power levers forward, you'll see an increase in N1. That equates to a sharper increase in torque, making the plane difficult to control on the ground.

 

The only way to fix it seems to be to build engine code outside the sim and bypass the MSFS turboprop model.

Folks, its simply not the case that there's no beta range!

Looks like a throttle hardware/calibration problem to me.

At idle with e.g. the condition levers at hi, Ng is 70% and the blade angle is 12deg

If you slowly reduce the throttle to -8% Ng stays at 70% while the blade angle reduces smoothly to 0 deg and (depending on the weight nice) and slows her down.

At -10% throttle the blade angle starts to become negative and the Ng starts increasing.

IMO the C90 is as easy to taxi as the P46T

Bernt,

 

Sorry...not a controller issue. I have my controller calibrated with the power lever detent at the ground fine gate position, and I took note of the positioning of the power levers as I performed this test.

 

With the condition levers set to high idle: Idle N1 is 70%. If I move the power levers aft from this position, N1 rises, torque increases and the tool tip shows I am in reverse. I can see the power levers in the VC moving into the reverse range. If I move the power levers forward from this position, the power levers in the VC move toward flight idle through the part of the power lever travel that SHOULD BE the beta range, but nothing happens at all until the tool tip indicates 13% forward, and then I get a rise in both torque and N1.

 

With the condition levers set to low idle: Idle N1 is 66% (which, incidentally, is incorrect...should be 58%). If I move the power levers aft from this position, N1 rises, torque increases, and the tool tip shows I am in reverse. Again, I can see the VC power levers moving into the reverse range. If I move the power levers forward, the VC power levers move toward flight idle and I get an instantaneous increase in N1 and torque.

 

With the default loading...pilot and copilot, no pax or baggage, full fuel...the aircraft does not start rolling until both engines are above 250 ft/lbs of torque or so, at which point, there has been a significant N1 rise.

 

What SHOULD be happening here is that at the ground idle gate, prop pitch should be 0 deg...zero thrust and minimal torque...and at the flight idle position, I should have 12 degrees of prop pitch. I don't have any way of measuring prop pitch here, but with the power levers at flight idle, I should see the same N1 as I do at the ground idle/ground fine position, but increased torque because of the increased propeller pitch. Since I'm seeing N1 and torque both rise, when I should not, the only thing I can conclude is that there is no actual beta range in this engine model.

 

From the FlightSafety manual for the C90A/C90B: "The function of the power levers is to establish a gas generator rpm through the gas generator governor

(NG) and a fuel flow that will produce and maintain the selected N1 rpm. In the Beta or GROUND FINE range, the power levers are used to change the propeller blade angle, thus changing propeller thrust."

With the condition levers set to high idle: Idle N1 is 70%. If I move the power levers aft from this position, N1 rises, torque increases and the tool tip shows I am in reverse.

 

That's really weird. Tested again with internal data readout etc. from 0% (flight idle) until -8% throttle (tooltip indication) the blade angle changes consitent from 12deg to 0deg. Ng stays at 70% all the time.

Have you tried moving the throttles with the mouse as well? (just for testing purposes) as there was a complaint about too little maximum torque which turned out to be a calibration error.

 

Edit: noticed that the idle throttle position in the VC is wrong as it's presently set at ground instead of flight idle. At the flight idle marking the throttles are already at their 27% position.

That might also cause some problems. I informed Carenado already about this problem.

noticed that the idle throttle position in the VC is wrong as it's presently set at ground instead of flight idle. At the flight idle marking the throttles are already at their 27% position.

That might also cause some problems. I informed Carenado already about this problem.

 

Thanks, Bernt. I'd tried moving the levers to the flight idle position for start (the POH cautions against moving the power levers aft of the flight idle gate while the engines are off), since that's where they should be, but I get 74% N1 there, regardless of whether the condition levers are in high or low idle, and I should be seeing idle N1 (58-70% depending on condition lever position).

 

On another note, maximum reverse N1 is low...I get about 74% at max reverse (whether I use the F2 key or the throttle quadrant power levers), and it should be more like 88%.

 

What are you using to get a readout on prop pitch?

1. I'd tried moving the levers to the flight idle position for start (the POH cautions against moving the power levers aft of the flight idle gate while the engines are off), since that's where they should be, but I get 74% N1 there, regardless of whether the condition levers are in high or low idle, and I should be seeing idle N1 (58-70% depending on condition lever position).

2. On another note, maximum reverse N1 is low...I get about 74% at max reverse (whether I use the F2 key or the throttle quadrant power levers), and it should be more like 88%.

3. What are you using to get a readout on prop pitch?

 

1. If you move the throttles to the flight idle gate you are already at 27% actual throttle (hence no difference with the condition levers at HI or LO). That one's going to be changed so that you are at 0% at the flight idle gate.

2. The 74% Ng during reverse is simply an FSX limitation to avoid severe prop overspeed

3. AFSD

Bernt,

 

I think the adjustment of the power lever 0% position to the flight idle position might help quite a bit. Thanks.

 

I'll give AFSD a try, so thanks for that, as well.

JJETMEC, Did you move the fuel levers to "Low Idle" ????

Wow, you must have something wrong. I turn on the Ign/Start Switch, wait for 10%, advance condition lever to Low Idle. Boom.

 

thanx guys for quick feedback, unfortunately, like i said in my original post, followed all checklists by the book, as printed by carenardo. i even have some stick time, and was an A&P mech on B1900D for US AIR EXPRESS working the PT6s, so now only followed carenardos lead, but also my own techniques, based on expereince..,then i just said what the heck, and tried every combination possible. so b/c no other reporting this issue, must have some bad code, or bad file, or something..so easy enough to uninstall, and re-install, or even re-download. if anyone comes up with other options, or ideas in the meantime let me know. i will give it a go..thanx jjetmec

hahaha... I just blindly paid $40 because I was so excited about it and have all the same issues here. I've never flown a sim plan with such a wierd transition to thurst reversing. I'm sure there is or will be a good sound replacement for this thing. Seriously is there no heading indicator knob? I didn't see it and just went on with my flight.

 

This is what I get for an impulse buy...

 

I am so rooting for this plane... I really really hope some of these basic issues are fixed.... Like being able to properly start it hahahaha.

Cool, do you think it will work (adding the Avidyne to the JetProp WX radar spot?) I do not know much about this stuff...

Seems like bliksimpie has read your wish. http://forum.avsim.n...0-ex500-in-p46/

 

Seriously is there no heading indicator knob? I didn't see it and just went on with my flight.

Find it on the 'pedestal', or the AP popop window or use the knob in the FO's side.

 

 

 

thanx guys for quick feedback, unfortunately, like i said in my original post, followed all checklists by the book, as printed by carenardo. i even have some stick time, and was an A&P mech on B1900D for US AIR EXPRESS working the PT6s, so now only followed carenardos lead, but also my own techniques, based on expereince..,then i just said what the heck, and tried every combination possible. so b/c no other reporting this issue, must have some bad code, or bad file, or something..so easy enough to uninstall, and re-install, or even re-download. if anyone comes up with other options, or ideas in the meantime let me know. i will give it a go..thanx jjetmec

 

You're not alone on start. I also ran the checklist religiously, the right gin and starter engage n1 rises to 12%, I advance conditioner to low idle and -----NOTHING! I did notice that there is no fuel flow and I here the ignition recycle but it won't start. I also tried all the fuel system settings and made sure I had gas. I don't hear the booster pumps engage and there is no fuel pressure warning.

 

Any ideas?

I really want to buy this. My head tells me to wait for the patches..

+1

 

 

David DD

 

+1

 

 

David DD

Why wait? The updates are free and you get to enjoy it as is for now. Just my opinion.

Seriously is there no heading indicator knob? I didn't see it and just went on with my flight.

 

Yess I see that now.. thanks

Why wait? The updates are free and you get to enjoy it as is for now. Just my opinion.

I'm not that sure I will get it anymore, I just want to see what will be adressed with the pacth.

I am kinda of disappointed there is no rxp integration and I would have loved some more attention to system modelling (for example the bleed air system that doesn't depressurize the aircraft, the prop behaviour not spot on). For example look at even the Malibu and the way the fuel flow values are off compared to the charts.

I do love the looks of all Carenado planes but I guess I getting a little bored by seeing the same flaws over and over...! That's why I will wait for the pacth to see what will be fixed.

 

 

David DD