The Flight Model Needs Some Serious Tweaking!

[Falcon900flyer 0]

Greetings,

 

Having some real experience (about 500 hours PIC) in a King Air 200, I thought I'd share some findings that may interest people. Chances are that these issues may have already been addressed by other posts, and in that regard I apologize for being repetitive. Ok, here's what I saw:

 

1. This aircraft requires a ridiculous amount of power just to get it rolling on the taxiway. My power levers are almost at the halfway position! In real life (speaking from a King Air 200 point-of-view), the aircraft should start rolling and slowly accelerate in idle power alone. In real-life, I'd have to jockey the power levers between idle and beta to keep a reasonable taxi speed. I'm sure this is the same in the real C90B.

 

2. When either in cruise or after touchdown and moving the power levers to idle, the aircraft decelerates but it does so way too slowly. Once those 4 bladed props go to flat pitch, the aircraft should decelerate significantly (That is again, from a BE20 point-of-view. I have a hard time believing that the C90B would be any different.)

 

3. There is too much of a lag when bringing up the power levers from idle. Yes, there is lag, but not to the extent shown in this sim. Also, the power takes way too long to stabilize once the power levers are brought up.

 

Don't get me wrong, this is a wonderful aircraft that Carenado has produced, but they could make it so much better if these issues were addressed.

Just my 2 cents...

 

John

[fppilot 4,389]

the aircraft should start rolling and slowly accelerate in idle power alone

 

That is exactly what happens to me with this Carenado C90. I must engage the parking brake to stay put, otherwise I slowly start to roll. I've just let it stay that way (idle) and before long I even pick up unrealistic speed. i.e. it gets above any reasonable taxi speed. I would expect the differences between your experience and mine on idle power may be an issue of calibration. I cannot speak to the other two issues you raised as I have no realworld hours in type.

 

-FP

[Falcon900flyer 0]

Thanks for your post, FP...I will recalibrate!

 

John

[fppilot 4,389]

.I will recalibrate!

 

Well, I may need to as well.

[V1VrV2 44]

Well, I may need to as well.

The same thing happens to me - the airplane rolls forward without application of thrust, torque at around 160 or so at "idle". I have, however, increased the static thrust to 100 (from 75) in the aircraft.cfg file so maybe that's doing it. ;)

[kaydub 3]

The same thing happens to me - the airplane rolls forward without application of thrust, torque at around 160 or so at "idle". I have, however, increased the static thrust to 100 (from 75) in the aircraft.cfg file so maybe that's doing it. ;)

 

Serious tweaking? You can't be serious. Even Realair states that their Royal Duke, although generally considered to be about the best dynamics out there, is a compromise due to the limitations of turboprop modelling in FSX. I have to bring my condition levers to low idle in order to hold position at idle on the ground without brakes. It doesn't require much power at all to initiate taxi even at low idle.

 

K

[mookie5913 0]

My CH yoke and pedals are fully calibrated and I still have the same problem as the OP, it takes over 400lbs trq just to get the thing rolling?

 

what am I doing wrong?

[Barnstormer1 0]

Here we go. The old RW pilots going to tell the computer how it should work. Computers are STUPID! and have many limitations. Now if one was a FDE expert?

 

Just jesting of course.

[HawkDsl 50]

Maybe you guys should check the cargo areas... you might be "innocently" being mueled for drug runners. :Thinking:

[dpcnh 0]

My CH yoke and pedals are fully calibrated and I still have the same problem as the OP, it takes over 400lbs trq just to get the thing rolling?

 

what am I doing wrong?

 

When that is happening, what are your conditioners set at? If at low idle, it would take more power. At high you should almost need not power at all. Look for a setting in between.

[V1VrV2 44]

Thought I'd test this while taxiing out for a long x-country flight today. Here's what I got:

 

Full fuel, 5 pax + luggage = 9800 lbs (300 lbs shy of MTOW)

Condition levers set for low idle yielding torque in the 160 range (props full forward, of course). Breakaway occurred at about around 260-275 ft-lbs of torque. Taxi was accomplished with throttles at idle and also required some braking to keep from speeding down the taxiway. Takeoff (i.e. 1315 ft-lbs torque) is accomplished with about 90% physical throttle movement on my throttle quadrant - and more and I'll bust the torque limit.

 

I'm using a CH Throttle Quad mapped via FSUIPC.

 

EDIT: One critical piece of information I inadvertently left out: I've increased the static thrust number in the aircraft.cfg file to "110". This was a remnant of some performance tweaking I did a while back and I left it. The original number is 75.

[mookie5913 0]

I use low idle for taxi, Im going to change the static thrust in the CFG file and see if that helps.

 

I took exact readings last night, breakaway at 600lbs trq and it shoots right to 23 or so knots :Thinking: then rest of taxi is somewhere around 400lbs trq, that was 200lbs short of MTOW

[mookie5913 0]

I just discovered what appears to be a bug!

 

I made the CFG change but when I when to taxi it still took over 700lbs trq to break loose, then I looked down and tapped the parking brake off then on very quickly and the aircraft began to move, it is almost like my p brake is sticking on?

 

anybody ever heard of this?

[fppilot 4,389]

Are you using CH pedals?

[zfehr 1]

In a real C90 you should be able to have NG set to 60% (you'll bring conditions levers up slightly), with idle power and props full forward you should see 1,200 rpm and the aircraft will start to move and taxi on its own to a fast speed. You'll need to use either beta (the rpm's will rise to a little over 1,500 but the NG shouldn't move... if the NG rises you've gotten into reverse which you should never do less than 40 knots) or alternately you can leave throttles at idle and feather the props which will bring rpm's down to about 400 and negate any thrust you would have. Using this second method to accelerate again go back to full forward pitch on the props but it will take quite a while for the oil pressure to build back up in the hubs and raise the rpms... you'll think nothing is happening for the first 5 or 10 seconds, then the rpm will slowly build back up. I haven't even futzed with the cfg settings to see if this can be made to work realistically in the sim. So far I've just put the conditions levers full forward, used some throttle to inititiate movement then use beta to control speed. Some of the prior recommended changes may work but the settings I listed are what you would see in the real aircraft.