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Indianajones

Slowing down the idle on certain aircraft

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Hey,

     Anyone know a way to change certain aircraft from moving as soon as you take off the parking brake? The Wilco A319 Vol.1 for FSXSE is particularly bad, the thing just runs off as soon as brakes are released and you have to brake almost constantly to maintain 20knts 

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Depending on the weight that can be realistic.

That's the reason why you have to monitior the brake temperature during taxi out. They can get too hot for takeoff when you have to taxi a looong way to the runway with a lightly loaded A319/320. 

To avoid this e.g.Boeing recommends to let the aircraft accelerate to 30kts, slow it down to 10kts and let it accelerate again.

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Thought Boeing would have said you should have taken a Boeing.

Single engine taxi could be a fix for that if the conditions and Company SOPs are ok.

 

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Harry Woodrow

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Single engine taxi out presents a few problems since you e.g. don't have anyone watching the engine during start, warmup time, not being able to accept an earlier than calculated/expected takeoff etc. 

Taxi in is in the meantime standard with most airlines, although the economic savings effect is questionable since the nosegear tire life is greatly decreased. 

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I think the reason for this is more FSX's poor tyre friction model rather than incorrect idle - changing the idle will also change its behaviour in flight, affecting the descent characteristics which the developers probably worked hard to get right.

There is (was?) a fix for the tyre friction bundled with FSUIPC, perhaps you could try that?  You might need the registered version, however, if you don't already have it.

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3 hours ago, lzamm said:

I think the reason for this is more FSX's poor tyre friction model rather than incorrect idle - changing the idle will also change its behaviour in flight, affecting the descent characteristics which the developers probably worked hard to get right.

Don't know the Wilco Airbus, but it's no problem to adjust idle thrust on ground so it doesn't affect the aircrafts behavior/performance in flight.

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55 minutes ago, FDEdev said:

Don't know the Wilco Airbus, but it's no problem to adjust idle thrust on ground so it doesn't affect the aircrafts behavior/performance in flight.

I’m confused? Are you you saying it can easily be done? There’s nothing with tire friction in the .cfg? Thanks everyone for your responses

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4 hours ago, lzamm said:

I think the reason for this is more FSX's poor tyre friction model rather than incorrect idle - changing the idle will also change its behaviour in flight, affecting the descent characteristics which the developers probably worked hard to get right.

There is (was?) a fix for the tyre friction bundled with FSUIPC, perhaps you could try that?  You might need the registered version, however, if you don't already have it.

Thanks, 

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32 minutes ago, Indianajones said:

I’m confused? Are you you saying it can easily be done? There’s nothing with tire friction in the .cfg? 

Yes. Every properly designed FDE achieves that, but again, depending on the weight this can be realistic behavior.

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4 hours ago, FDEdev said:

Don't know the Wilco Airbus, but it's no problem to adjust idle thrust on ground so it doesn't affect the aircrafts behavior/performance in flight.

So ironically also the aircraft has a real problem slowing on descent so honestly I wouldn’t mind changing the idle thrust on the ground and in the air, got any ideas on the best way to do that?

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2 minutes ago, Indianajones said:

So ironically also the aircraft has a real problem slowing on descent so honestly I wouldn’t mind changing the idle thrust on the ground and in the air, got any ideas on the best way to do that?

That's not ironic. With a jet you can either slow down or descend, but not both at the same time (without speedbrakes). I suggest you learn how to correctly fly the A320 instead of starting to alter the flight dynamics.

Have you worked with air files before? 

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9 hours ago, lzamm said:

There is (was?) a fix for the tyre friction bundled with FSUIPC, perhaps you could try that?  You might need the registered version, however, if you don't already have it.

I am a registered FSUIPC user.  Where can I find the dynamicfrinction.lua script?  I cannot locate it on my system.

Please disregard.  I found it.


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51 minutes ago, FDEdev said:

That's not ironic. With a jet you can either slow down or descend, but not both at the same time (without speedbrakes). I suggest you learn how to correctly fly the A320 instead of starting to alter the flight dynamics.

Have you worked with air files before? 

This isn’t just normal flight characteristics I’m talking about Wilco has had this problem before, 1,000 Fpm descent speed brakes almost fully out and the speed tape doesn’t move, supposedly at idle thrust, also descending through dense air below 10,000 doesn’t change anything, I have to wait until I get to final approach altitude before I can really get the speed down, however I don’t have a ton of time flying it so it could be the FMGC still trying to hold a certain descent speed parameter even though I’ve taken manual control of the speed, no I have not messed with air files only .cfg for lights and such, I will study up on it 

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6 minutes ago, Indianajones said:

This isn’t just normal flight characteristics I’m talking about Wilco has had this problem before, 1,000 Fpm descent speed brakes almost fully out and the speed tape doesn’t move, supposedly at idle thrust, also descending through dense air below 10,000 doesn’t change anything.

That's definitely way off, even at low IAS. At e.g. 62t the A320 and 250kts the ROD without speedbrakes should be 1600fpm and with the boards out 2500ft/min.

It would be interesting if the problem is too high thrust or too low drag.

 

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9 minutes ago, fppilot said:

I am a registered FSUIPC user.  Where can I find the dynamicfrinction.lua script?  I cannot locate it on my system.

 

Have a look at this:

https://forum.simflight.com/topic/75702-dynamic-friction-with-fsuipc-4923/

I'm sure there are many others, including on AVSIM, but that's just the first one that came up when I googled "FSUIPC friction".

It's been a long time now so the details are hazy, but it works a treat.

 

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