JRBarrett

Maybe a bit less taxi N1

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The original setting of 24 percent for ground idle was probably too low for taxi at higher weights without constant thrust adjustments, though when light, even 24 percent was not bad once the aircraft was moving.

But, perhaps the new value of 31 percent is a little high. Even at a gross weight of 36,000 pounds, I found that I had to ride the brakes constantly to keep from accelerating in taxi at idle.

(This in P3D 4.3).

Maybe 27-28 percent might be a better compromise target?

During takeoff and climb though, I think the new N1 values are much, much better. Previously, especially when light, the acceleration and rate of climb were excessive. Now, the climb N1 values seem a lot closer to those in the performance tables, and there is time to retract the flaps and slats realistically without having to pull the power way back to avoid entering overspeed territory. 

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A pilot and i spent an entire evening comparing our airfile with real word vids to get better accuracy. In 2 vids we found both had an idle of 31.4% N1 and both never touched the throttle to taxi. This is what we are using. We also updated the performance for climb and cruise. And i wrote a new code for the ITT as you might have read. I am pretty happy with the new taxi. No sticky tarmac issue and seems to taxi at 12 knots and i simply brake to 5 knots to make a turn.

 

P.S. This vid confirms the over sensitive steering. Listen to the instructor after they land.

 

 

Edited by Flysimware
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2 hours ago, Flysimware said:

 In 2 vids we found both had an idle of 31.4% N1 and both never touched the throttle to taxi. This is what we are using. 

This vid confirms the over sensitive steering.

Do you have a link for those 2 vids? I only found videos with a 25% idle N1.  AFAIK  31% are valid for the -3 engines.

The problem in the above video isn't the over sensitive steering, it's the combination of operating the toe brakes and trying to steer at the same time. 

It takes quite a bit of practice to apply 100% symmetrical braking. 

Edited by FDEdev

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2 minutes ago, FDEdev said:

Do you have a link for those 2 vids? I only found videos with a 25% idle N1.  AFAIK  31% are valid for the -3 engines.

Yes. I would like to see the vid with 25%. Because both vids show no movement of the throttle and its 31.4% N1 but the vids only show taxi never sitting on tarmac.

 

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19 minutes ago, FDEdev said:

Both videos are showing Falcon 50s with the -3 engines. (confirmed by the 99% T/O N1)  The -40 engines have a much lower T/O N1.  (90% at low altitude).

Here's an EX video:   https://www.youtube.com/watch?v=Tn6jctaZvcU&t=50s

 

We used the -2 for specs. But as for the EX video that idle wil not concern us. Be nice to find a video of the F50 showing idle. I believe its 31.4 as during taxi in 2 vids they never change and they are the same.

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32 minutes ago, Flysimware said:

We used the -2 for specs. But as for the EX video that idle wil not concern us. 

I'm confused. -2?  31% idle is correct for the -3 engines but I thought the Flysimware Falcon 50 simulates the -40 engines?

Edited by FDEdev

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4 minutes ago, FDEdev said:

I'm confused. -2?  31% idle is correct for the -3 engines but I thought the Flysimware Falcon 50 simulates the -40 engines?

Why did you think the -40. And like you said the T/O would be 90% not 98.7% N1. Do we state the -40 in our documentation? I need to fix that.

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4 minutes ago, Flysimware said:

Why did you think the -40. 

Because the idle N1 used to be 25%.

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Just now, FDEdev said:

Because the idle N1 used to be 25%.

I did not have info on what the idle was. Our plan was to design the oldest original F50.

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5 hours ago, Flysimware said:

Why did you think the -40. And like you said the T/O would be 90% not 98.7% N1. Do we state the -40 in our documentation? I need to fix that.

On the lower part of the Shift-1 screen, where you can select whether to have all systems running, or all systems off.

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The exact idle N1 you end up with can vary based on pressure altitude (field elevation) and temperature. The older N2-regulated engine computers in the Falcon 50 with -3 engines don’t have a fixed idle N1, which is why the yellow idle arc on the N1 gauge goes from approx 24 to 31.

I think at ISA near sea level it would be closer to 31.

The newer TFE731 engines use N1-regulated computers. Those have a constant idle N1. The computer switches on the overhead panel when the aircraft has N1 DEECS has three positions: “off” “manual” and “auto”.

I think that is how they are configured on the 50EX with -40 engines. It is that way on the 900 which uses -60 engines.

With N1 computers, Max takeoff N1 is automatically calculated based on termperature, so in “auto” mode, you can firewall the throttles on takeoff, and N1 will not exceed the calculated value.

I’ll check our TFE731 engine manual at work later today. (The manual covers all variants). I think there is a graph that shows idle N1 vs. temperature/pressure altitude for the -3 engines with N2 computers.

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Installed  ver 4.8 and done a test climb to 37000', GW 37400. Max fuel.

The inial climb out went ok but around fl160 something went a miss, loss of speed ., veered up,slats appeared to be deployed. must have lost concentration. however levelled off and continued withthe climb at 2500fmp, .72mac,85% N1 increasing to 93%N1 to reach FL370, decreasing climb rate to 1500fpm for the last 2000'to 3000'

Cruise .8mac, 76.1%N1, N2 80%, PPH 7x100

Are these the figures I should be looking out for.

bob

 

Edited by onebob

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8 hours ago, onebob said:

Installed  ver 4.8 and done a test climb to 37000', GW 37400. Max fuel.

The inial climb out went ok but around fl160 something went a miss, loss of speed ., veered up,slats appeared to be deployed. must have lost concentration. however levelled off and continued withthe climb at 2500fmp, .72mac,85% N1 increasing to 93%N1 to reach FL370, decreasing climb rate to 1500fpm for the last 2000'to 3000'

Cruise .8mac, 76.1%N1, N2 80%, PPH 7x100

Are these the figures I should be looking out for.

bob

 

Autoslats will deploy if you stall. 

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9 hours ago, JRBarrett said:

The exact idle N1 you end up with can vary based on pressure altitude (field elevation) and temperature. The older N2-regulated engine computers in the Falcon 50 with -3 engines don’t have a fixed idle N1, which is why the yellow idle arc on the N1 gauge goes from approx 24 to 31.

I think at ISA near sea level it would be closer to 31.

The newer TFE731 engines use N1-regulated computers. Those have a constant idle N1. The computer switches on the overhead panel when the aircraft has N1 DEECS has three positions: “off” “manual” and “auto”.

I think that is how they are configured on the 50EX with -40 engines. It is that way on the 900 which uses -60 engines.

With N1 computers, Max takeoff N1 is automatically calculated based on termperature, so in “auto” mode, you can firewall the throttles on takeoff, and N1 will not exceed the calculated value.

I’ll check our TFE731 engine manual at work later today. (The manual covers all variants). I think there is a graph that shows idle N1 vs. temperature/pressure altitude for the -3 engines with N2 computers.

Our TFE731 manual doesn’t have the -3 after all - only the -20, -40 and -60 with N1,DEECS. But in any case, taxi power seems quite good in Beta 4.8

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I noticed after a quick first test that you can fly at 4000ft with the engines at idle and the aircraft will not decelerate below 160 kts.  It will just fly nice and level with the engines at idle.  Is this correct?

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1 hour ago, NeilC said:

I noticed after a quick first test that you can fly at 4000ft with the engines at idle and the aircraft will not decelerate below 160 kts.  It will just fly nice and level with the engines at idle.  Is this correct?

No that is not correct. I wonder if the new flight dynamics screwed up my low altitude power settings. Will check this today.

Update: The idle was at 35% N1. Should be roughly 31.4% N1 at low altitude. Adjusted the air file and now it stays at idle at lower altitude. Also this was good that you pointed this out because since we did improve the FD the gear warning for below 160kts code needed to be adjusted so the minimum throttle to disengage the warning will maintain a minimum of 160 knots.

I also made the airspeed reference marker move 5 X faster for wheel and fine tune with L/R clicks. This will be handy.

 

Edited by Flysimware
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