Taxi on 1 engine?

[AirbusCaptain 0]

Is it possible without the plane trying to turn hard to one side of which Ever engine is not running? In real life aircraft don't seem to have trouble at all doing this. Is this a flight sim limitation? Or is there something within FSUIPC, etc I'm missing out on?

[MadDog 353]

It's not FSUIPC, it's a simulator "limitation". I've always felt that ground handling is the weakest aspect of the flight engine. It always takes a little too much thrust to start moving and the aircraft comes to a stop too quickly when thrust is reduced... conversely, side-to-side motion (i.e. yawing, turning) seems to have very little friction. Think of the pavement as a thin line of sand directly in front of the nosewheel with sheets of ice on either side... a slight motion right or left often results in exaggerated yaw. Tweaking the .air file can help (but not completely eliminate) the behavior.

[robertschiele9 1]

After a landing at EGLL in a Posky Boeing 767-300, I once inadvertently killed the #2 engine, and found the aircraft to be virtually unmaneuverable while trying to taxi until I realized my mistake, fired up #2 again, and went happily on my way (even if a bit red-faced).

[ronzie 21]

The OP mentioned FSUIPC. If it is a registered version investigate the tiller which reduces steering sensitivity in the cenrer of the range when airspeed is below a certain value. This is an emulation for jet aircraft that contain nosewheel steering by tiller for taxiing.

 

Also in the FSUIPC registered version you can map the yaw axis (nosewheel, rudder) or other ones non-linearly to achieve less control effect in the center of the range. This can be mapped by aircraft if you wish. This lets you preserve full yaw affect when needed while reducing over steering during taxi.

 

Prop aircraft can generate more side pulling on an offset engine taxi (one side) because P-factor and torque come into play than on a jet. Realism settings in FS can affect that. I have seen Beech King-Airs in the real world perform single engine taxiing. In the King-Air r/w I believe the dead prop auto feathers so there is no induced drag and to keep the prop from spinning without oil pressure. While that drag would be minimal it still is something to think about. Multi-engine props can have counter rotating props to cancel out torque effect and you lose that with one engine out.

 

My POSKY CRJ200 jet exhibited a fast idle taxi once past inertial resistance to getting started and past turns. In their forums way back it was suggested to use one engine for taxiing. Only when starting to roll or accelerating was there a significant pull.

 

One thing I have not verified in FS9 is if using F2 you can use just one click to open reversers but keep idle thrust for restricting taxi speed.

 

When taxiing with ground winds present especially on light aircraft be sure to trim/keep the nose down for added pressure on the nosewheel for better steering control.

[BenW 0]

Very hard to taxi SE in FS9. I tried it in the ifly 737 (which has a decent ground handling model) and I needed almost takeoff levels of thrust to move the thing and then the yaw was almost uncontrollable. Thankfully the Jet A1 in FS is free!

[AirbusCaptain 0]

So basically What im getting here is it can't be done...?

[BenW 0]

It can be done but due to the way FS9 models ground friction and other variables then it's very difficult. In real life most jets will taxi happily on idle thrust only. In FS9 they won't so you need to give it lots of gas and doing that on one engine gives you huge amounts of yaw. It's doable but see-sawing down the taxiway with huge applications of thrust would be unacceptable in terms of passenger comfort and safety.

[Egbert Drenth 250]

So basically What im getting here is it can't be done...?

 

I'm using a low friction patch for FS9, reducing the ground friction considerably.

After applying some thrust, my aircrafts taxi on idle which most do irl too.

 

Search for a modified sim1.dll, I think it is available in the AVSIM library.

If you use it, backup your original, so you can revert back if you don't like it.

[TrevorS 54]

Two things are necessary:

 

1. Start with the modified sim1.dll as Egbert has suggested - it makes a world of difference.

 

2. Adjust the idle thrust in the air file - It is in section 1506 - adjust the value for 25% N1 (maybe also for 20% and 30% , depending)

 

I have replaced the sim1.dll and adjusted idle thrust on all my aircraft and taxiing is now a pleasure.

 

Also, you made need to change the surface of the runway or taxiway in AFCAD - bad surfaces are not accurately implemented in FS9 causing the aircraft to "bounce" along the surface.

 

Trevor

[geoffco 0]

Two things are necessary:

 

1. Start with the modified sim1.dll as Egbert has suggested - it makes a world of difference.

 

2. Adjust the idle thrust in the air file - It is in section 1506 - adjust the value for 25% N1 (maybe also for 20% and 30% , depending)

 

I have replaced the sim1.dll and adjusted idle thrust on all my aircraft and taxiing is now a pleasure.

 

Also, you made need to change the surface of the runway or taxiway in AFCAD - bad surfaces are not accurately implemented in FS9 causing the aircraft to "bounce" along the surface.

 

Trevor

 

Interesting. I have been using a modified Sim1.dll for some time (I edited it myself following some instructions from another forum) but have not tried also editing the air file... What change do you recommend for the idle thrust factor? I have set about a 10% increase just now but not yet tested it...

 

Geoff

[cbrown 1]

I searched Avsim, Flightsim, and Simviation for sim1.dll with no results. Any idea where it can be obtained and under which name? Thanks.

 

Colin B

[TrevorS 54]

Geoff

 

For me it's a case of trial and error. I change the value for idle then test........... until I am satisfied.

 

 

 

Colin B

 

If you PM me your e-mail ad, I can send you a copy of mine.

 

Trevor

[ronzie 21]

Regarding turbo-prop taxiing:

 

Most have a ground idle (beta range) and a flight idle position either as a separate axis or in combination with another control. If you are in flight idle that applies a high rate of idle power than ground idle. In this case once you get moving you might have too much thrust for taxiing.

 

The reason that option is in turbo props is because of the increased spool up time and using a higher idle reduced that spool up time for more immediate effect on thrust changes when in flight or initiating take-off. So if your turbo prop is taxiing too fast be sure you are in ground idle mode. For take-off move it into flight idle just before you taxi into position for take-off to reduce spool up time when you advance to full power for your take-off roll. Never move the control to ground idle until you have safely slowed the aircraft on the runway insuring you have enough roll-out left. Maintaining flight idle during approach gives you the reduced time to initiate a spool-up for a go-around. Not setting ground idle in flight is a usual operating restriction required by air operator rules.

 

Jet aircraft do not require nor have this idle type setting.

[TrevorS 54]

Hi Colin

 

Got your PM - but I need your e-mail ad

 

Trevor

[kavs8 10]

Hi Colin

 

Got your PM - but I need your e-mail ad

 

Trevor

 

Hi mate, could you send this on to me too? jackoneillcork@hotmail.com appreciate it