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Speed button not working


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I am probably doing something wrong, as I am not an expert when it comes to the CRJ

But whenever i try to set speed (throttle is set to climb etc) it shows that its armed (green lights) by the speed just keeps increasing (past set limit) and sometimes it turns it self off automatically. 
It is really frustrating because no matter what I try I cant seem to get the speed to hold

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speed mode is a vertical mode of operation, so first you set the altitude you want to get to and then engage speed mode - FD will command AP to get to selected altitude at your given speed (either by climbing or descending, you'll see CLB or DES in PFD annunciator area). with this mode of operation you'll notice your VS being the variable set by FD to achieve your target speed. on the other hand if you climb or descend in VS mode you set your target VS and your speed is the variable that will arrive at some value (not controlled directly by you) to achieve proper VS. so basically two ways of achieving the same thing, you just control different parameter leaving the other in the hands of FD and physics :)

 

i hope i made it clear enough, just yesterday was trying to understand speed mode, because it's not really what you might expect it to be. important thing to remember is that it is vertical mode of operation, not horizontal (so setting it up to 300kts in the cruise phase won't make the aircraft travel with this speed; that you may achieve only with your throttle operation, which in CRJ is left in pilot's hands with no automatic control).

 

speed mode will disengage itself automatically after reaching selected altitude (similarly to VS mode), after which FD will switch to ALT HOLD mode, which basically means that if you forget to lower the throttle after climb, the aircraft will level of and your speed will go through the red roof ;)

 

cheers, Hubert.

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I've noticed that if you arm Speed mode prior to engaging the autopilot it doesn't work in some situations. Namely if you use the SYNC button. In the real aircraft I would always use the SYNC button to move the FD and speed to my current position. In the sim if you do this even though speed mode shows armed you have to click it again before it actually works as intended. VS mode does the same thing when activating it from cruise. You have to press it twice before it actually works for some reason.

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  • Deputy Sheriffs

Hello Matthew,

If this happens to you again, please take a screenshot where we can see both the MCP (autopilot panel) and the PFD. This was we can see exactly which modes are active for the flight director to follow at the time the issue happens.

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After many flights where SPD mode worked well, now it doesnt want to catch up. I have set .77 mach speed to climb, but it just flies to nearly .80 mach and slowly climbing between 0-600fpm. 

Throttle in CL detent, anti-ice off

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On 3/23/2021 at 2:04 AM, Phantom_737 said:

I've noticed that if you arm Speed mode prior to engaging the autopilot it doesn't work in some situations. Namely if you use the SYNC button. In the real aircraft I would always use the SYNC button to move the FD and speed to my current position. In the sim if you do this even though speed mode shows armed you have to click it again before it actually works as intended. VS mode does the same thing when activating it from cruise. You have to press it twice before it actually works for some reason.

I had noticed something like this myself. I sometimes had to give it a second press but I thought I might have missed the button.

Now that my Bravo is finally all setup properly it should be easier for me to tell.

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