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dnagato

Automatic throttle - bug

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Hi people. When I stay full ILS, we reduce speed, example, get LOC with 180knots flaps 15, gear down check then we start to reduce speed to minimal safe for landing like 138knots for example, we put in MCP the speed 138knots, autothrottle in ON, we see the throttle start to down, but why the throttle not come for idle position for incriase reduction speed for safe landing ? I repair when use fly level change the throttle work fine, como for idle position or when use VNAV they works good, the problem is only when I stay for landing usually after gear in down. N1 stay between 37% - 40%. How reduce speed easy with this problem ?

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I think this is the normal idle range for the approach mode. "Approach idle is selected in flight if flaps are in landing configuration or engine anti-ice is ON for eitherengine. Approach idle provides a higher % RPM than flight minimum idle improving engineacceleration time in the event of a go-around. Approach idle is maintained until TBD-seconds aftertouchdown, when engine idle speed is reduced to ground minimum idle." Dan.

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I think this is the normal idle range for the approach mode. "Approach idle is selected in flight if flaps are in landing configuration or engine anti-ice is ON for eitherengine. Approach idle provides a higher % RPM than flight minimum idle improving engineacceleration time in the event of a go-around. Approach idle is maintained until TBD-seconds aftertouchdown, when engine idle speed is reduced to ground minimum idle." Dan.
This is exactly what you are seeing; I already asked about this. In real life, you get approach idle with the thrust levers actually on idle (when the other criteria are active), but pmdg explained that the only way to do it in the sim was to make the actual thrust levers advance a little.

Boeing777_Banner_Pilot.jpgsig_TheBusIveBeenWaitingFor.jpg

Alfredo Terrero

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I have seen the same thing also i level change and VS also. without flaps in landingmode and anti Ice on at around 30.000 feet
Not sure I understand what you mean?Are you at 30000ft in landing mode?Is engine anti ice on?Are you landing without flaps? Dan.

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Not sure I understand what you mean?Are you at 30000ft in landing mode?Is engine anti ice on?Are you landing without flaps? Dan.
Me to ...I not understand .

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It sounds to me like what you're describing is normal. When you're in the landing configuration and on the glideslope, the autothrottle will command enough power to maintain the commanded speed and stay on the glideslope. As another poster said above, the airplane is designed this way so that the engines remain spooled up for a faster response in the event of a balked landing/missed approach. Try this: fly the ILS approach with the autothrottle off. Once you've got gear down and 15 degrees flaps, pull the power all the way off and try to fly the approach that way. My guess is that you'll still see approximately 40% N1 as your minimum power (flight idle), and that you won't be able to maintain VREF+5 while remaining on the glideslope.


Best Regards,

Kurt "Yoda" Kalbfleisch

Pinner, Middx, UK

Beta tester for PMDG J41, NGX, and GFO, Flight1 Super King Air B200, Flight1 Cessna Citation Mustang, Flight1 Cessna 182, Flight1 Cessna 177B, Aeroworx B200

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Hello Take a look at this video. And you will see what i mean.Only when I press F1 the trottles goes all the way back to idle
pål
Like I said, this is the only way pmdg could get accurate engine n1's. You probably have seen default fs aircraft have a higher n1 when at higher altitudes, but in order to get accurate n1 vs altitude (or in approach idle mode which the real planes engine control does without moving the throttles) pmdg had to make the throttles move a little to get the accurate thrust. They told me they could have just made up the correct n1 values depending on alt, or if the plane is in approach idle mode, but they said that in order to get an accurate engine simulation, they had to actually increase the engine n1 via the thrust lever (while not looking right, this will give us an accurate simulation of engine n1's basically).

Boeing777_Banner_Pilot.jpgsig_TheBusIveBeenWaitingFor.jpg

Alfredo Terrero

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I have a SAS 737-800 DVD and in Level change mode from around 30000 the N1 value does not go below 37.8%. This will be dependent on speed and temp so I'm happy with the values I'm getting, as someone else said PMDG have used this method to control the FLIGHT Idle and APPROACH Idle modes. Dan.

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