First of all,I'm just a junior school student from China.My English is not well,and maybe there are some spelling mistakes or grammar's.Hope you understand.First,When I used NGX,I found that it couldn't taxi at IDLE.It must used about 22% or 23% to maintain speed.In fact,it only need IDLE to taxi in the real world.Second,when I turned off the runway after a nice landing,I found spoiler couldn't get down by itself.Why the spoiler must get down manually when I increasing power?Don't laugh at me because of my bad English,thanks.

Your English is a lot better than a lot of students that graduate from our high schools in the US. Congratulations.As to your question, I have no problem at idle and low weights, but I haven't tried at any heavy weights. This could make a difference. You are not much above idle which is 20% and it may take a slight nudge above 20% to get started rolling.Tom Hibben

Edited January 15, 201214 yr by THibben

OK,thanks for your answer and your evaluate of my English.I think I have some problems on the expression.My problem is "Why can't I maintain my speed(such as 20KTS) at IDLE when the weight is heavy",not 'Why can't I start rolling at IDLE.'when I'm rolling,more time I have rolled,more speed I have lost..So I must to increase power to get speed.Maybe I should try rolling in a light weight.Colin

It all depends on the weight. I'm not an expert, and there are many on these forums, but what I find is with, for example, 1/3 fuel and full passengers and cargo you need about 28% N1 to get moving and then 25% or a little less for taxi. I just use the brakes to slow down if I'm going too fast. The aircraft has plenty of momentum so you can throttle back to idle and it'll continue moving but gradually slow down. In the real world you can hear the engines are not at idle while waiting to get onto the runway but the plane is stationary so the captain must be applying the brakes (or maybe the parking brakes).

Ok,I understand.Thanks for your answer.

FSX has a bug where excessive thrust is required while taxiing. It's a minor difference from reality, and doesn't really effect realism too much. Takeoff performance is unaffected and still perfectly realistic.Your english is excellent.

Congratulations on your english, it's a lot better than my chinese! Welcome to the forumsIt's normal to add thrust to start taxing (breakaway thrust) then reduce thrust to maintain taxi speed. How much needed depends on your weight.

Ok,I understand.Thanks for your answer.

And for your second question:The NGX can retract the spoilers on the ground with an advance of thrust. I've found that it requires slightly more than I'm used to, especially after using the MD-11 which requires very little. I usually land and at the turn to taxi off, I'll do a very quick advance to about half and then back to idle. Don't give the engines time to spool, and it usually takes me all of 1/4-1/2 a second for that manual spike.

Some RW pilots will not advance throttles after landing and stow manually the speedbrakes.

The taxi thrust is as close as we can make it given the problems FSX has with the ground coefficient of friction, not much more we can do without screwing up the rest of the engine's range in flight etc.Your English is extremely good as others have said, I've seen far far worse in support tickets!

Probably including mine.