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SRS not commanding V2 + 10


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Question.  After departure flying the A320, the SRS should command V2 =10 kts.  Prior to departure the speed tape shows V2 at 129 kts.  During the initial climb, SRS has not increased to V2 + 10, although it shows active in the FMA col 2.  Also, I don't
think the Speed tape is representing Alpha Floor correctly.  Alpha Floor appears to be to fast.  Departure weight out of KSFO runway 1R is 144,000 lbs and V2 is 129 kts as displayed in the PERF Page.






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Screenshot (9).png

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Everything is setup correctly, as far as I can tell.  There may be a glitch when I switch from "Ready to Taxi" to Ready for Takeoff".  It seems that when I run all checklist with the aircraft in the "Ready for Takeoff Mode", the aircraft responds as it should.  I will investigate further.  This is a new sim for us.  Previously, we used the FSLabs A320 simulator running on P3Dv3.


Merry Christmas,



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The speed tape does not show alpha floor. In normal law it shows Vls , alpha prot amd alpha max. Alpha floor is an auto thrust mode.

Alpha floor is not pitch dependent.

From the fcom-

Alpha-floor protection automatically sets the thrust at TOGA thrust, when the aircraft reaches a very high angle of attack.

The Flight Augmentation Computer (FAC) generates the signal that triggers the alpha-floor mode. This, in turn, sets TOGA thrust on the engines, regardless of the thrust lever positions (Refer to DSC-22_30-90 A/THR Modes - General).

The FAC sends this signal when:

  • The angle of attack is above a predetermined threshold, that is a function of the configuration.

  • In CONF 3 and CONF FULL, this threshold decreases as a function of the aircraft deceleration rate (down to – 3 °).

Alpha-floor is available from lift-off until the aircraft reaches 100 ft RA in approach.


The αfloor is activated through the A/THR system, when:

  • α is greater than αfloor (9.5 ° in configuration 0; 15 ° in configuration 1, 2; 14 ° in configuration 3; 13 ° in configuration FULL), or

  • Sidestick deflection is greater than 14 ° nose up, with either the pitch attitude or the angle-of-attack protection active.

    The αfloor function is available from lift-off to 100 ft RA before landing.

Alpha-floor is inhibited above M 0.6.

Alpha-floor is inhibited when TCAS mode is engaged (Refer to DSC-22_30-50 AP/FD Modes General).

  • Alpha-floor is lost, when one of the following combinations of failures occurs:

    • SFCC1 and FAC2, or

    • SFCC2 and FAC1, or

    • Both FCU channels, or

    • 1 EIU, or

    • Both FMGCs.

  • Alpha-floor is lost under alternate or direct flight control law.

  • Alpha-floor is lost in engine-out, when slats/flaps are extended.

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Correct.  Alpha Floor is an AUTOTHRSUST protection.  I think I meant Alpha Max.   My point is, the Speedtape presentation is not correct.  I think the problem is that I set up the cockpit while running the APU.  When I set "READY FOR TAKEOFF" that is when the sim seems to have lost some data after engine start..                       


Happy New Year,



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