Changing The Idle RPM Fopr An FSX Aircraft

RandyL AT DOT

unread,

Oct 28, 2010, 11:57:03 AM10/28/10

to

I have a favorite FSX aircraft that I fly often. I really like this
aircraft, but it does have an annoying little glitch that I would like to
fix. If I retard the throttle all the way then the RPM goes down under
600-700 RPM and the engine dies. This is particularly annoying while
landing, as I often have to re-start the engine in order to taxi off the
runway. Is there a parameter in the aircraft.cfg or the "xxxx.air" file that
I can change so that when the throttle is at idle, the RPM never goes below
a certain RPM? If I keep the RPM above about 800 RPM then the engine doesn't
quit. Any help or suggestions would be greatly appreciated. Thanks...

Randy L.

-- "Question: What is the difference between today's economic depression,
and the Great Depression of the 1930's?"
"Answer: This one is in color."

Danny

unread,

Oct 28, 2010, 4:29:25 PM10/28/10

to

You might look in the aircraft.cfg [GeneralEngineData] and see if there is a
line for min_throttle_limit=0.0.
Change that to something like 0.05000 and see what the result is. If still
killing the engine, try 0.0900, or even 0.100 and begin to tinker with
that line to see if it will stop the shutdown. You will still have to turn
fuel off to stop the engine. One of my planes has a 0.02423 or something
like that. Most have the 0.0

I am not certain that will resolve the problem but worth a try. I have a
good friend who has been tweaking planes for a long time and he can answer
the question if my suggestion does not work.

"RandyL" <rlink(AT)cableone(DOT)net> wrote in message
news:xI2dnVCjwIDXAFTR...@giganews.com...

Gregory

unread,

Oct 29, 2010, 7:09:18 AM10/29/10

to

On Thu, 28 Oct 2010 09:57:03 -0600, "RandyL" <rlink(AT)cableone(DOT)net>
brought the following to our attention:

The throttle response and idle settings in FS are coded in AIR file
tables 1503 & 1504 IIRC. An example below of CN2 (corrected N2)
turbine speed when the throttle is closed at sea level. Also a contour
at Hi-Alt (defined by the IAP?)

http://home.comcast.net/~flightsim/1503_limits.png

Table 1504 is the same only at high Mach?

There seems to be a scalar in the aircraft.cfg file that will tweak the
idle RPM. The real way to tune the FD is to generate a new throttle
response curve and burn it into the AIR file which is binary. See the
guy over at mudpond for AIR burners (what's his name again?)

-G

Randy L.

unread,

Oct 29, 2010, 9:58:05 AM10/29/10

to

Thanks Gregory, I have AirEd, so I'll fiddle around with that and see what I
can get.

Randy L.

"Gregory" <flights...@bkwds.comcast.net> wrote in message
news:1aalc6t5utenbpk2f...@4ax.com...

Randy L.

unread,

Oct 29, 2010, 10:04:00 AM10/29/10

to

Thanks Danny, I'll fiddle around with that and see what I get. I'm flying a
normally-aspirated piston single, so I usually shut the engine down by
leaning the mixture all of the way. Take care.

Randy L.

"Danny" <drm...@yahoo.com> wrote in message
news:iacmf8$ql3$1...@news.eternal-september.org...

guyo

unread,

Oct 29, 2010, 11:59:50 AM10/29/10

to

I've the opposite problem, in all planes of FS9, the idle is far too high
and have to use brakes continuosly,
There is a solution?

"RandyL" <rlink(AT)cableone(DOT)net> ha scritto nel messaggio
news:xI2dnVCjwIDXAFTR...@giganews.com...

RandyL AT DOT

unread,

Oct 29, 2010, 12:32:48 PM10/29/10

to

Hi Danny,
I set the min_throttle_limit parameter to 0.04, and I now get almost
exactly 1000 RPM at idle throttle setting. This is not enough thrust to
cause the aircraft to start rolling, but it is enough to keep the engine
turning over. Thanks again for the help!

Randy L.

-- A problem is only a problem
if we make it a problem.

"Danny" wrote in message news:iacmf8$ql3$1...@news.eternal-september.org...

Dallas

unread,

Oct 29, 2010, 5:23:02 PM10/29/10

to

On Fri, 29 Oct 2010 17:59:50 +0200, guyo wrote:

> I've the opposite problem, in all planes of FS9, the idle is far too high
> and have to use brakes continuosly,
> There is a solution?

Sounds like throttle calibration problem.

If you think it's calibrated correctly, then uncheck the throttle axis in
controls and just use the keyboard to control the throttle. If the problem
goes away using the keyboard... (and it will)... then you have a wonky
throttle.

--
Dallas

guyo

unread,

Oct 30, 2010, 2:56:07 AM10/30/10

to

It is a new PRO FLIGHT YOKE SYSTEM !! If true what you say, I'll send it
back.

"Dallas" <Cybnorm@spam_me_not.Hotmail.Com> ha scritto nel messaggio
news:ez5d2xvnorfb$.12vtamj1kchfs$.dlg@40tude.net...

Danny

unread,

Oct 30, 2010, 9:53:08 AM10/30/10

to

Do you have the registered version of FSUIPC4 (for FSX). It has a much
better calibration feature than that built into windows.

"guyo" <xxxgr...@NOSPAMalice.it> wrote in message
news:4ccbc199$0$45269$4faf...@reader4.news.tin.it...

guyo

unread,

Oct 30, 2010, 12:21:39 PM10/30/10

to

I've registered version for FS9 which sim I'm still using.

"Danny" <drm...@yahoo.com> ha scritto nel messaggio
news:iah808$s2h$1...@news.eternal-september.org...

Danny

unread,

Oct 31, 2010, 9:48:47 AM10/31/10

to

So I take it FSUIPC calibration routine did not help. Dunno what to say
except...refer to post by Dallas.

"guyo" <xxxgr...@NOSPAMalice.it> wrote in message

news:4ccc461a$0$13470$4faf...@reader2.news.tin.it...