new to the ATR and ran into an issue. when setting a lower altitude, enabling VS mode, and rolling the nose up/down wheel to -500fpm, the plane begins to descend for about 5 seconds, but then “MONITOR SPEED” appears on the PFD and the entire descent is cancelled.

I can not get the AP to continue my descent at all. Anyone know why this is happening and how to circumvent it?

& your thrust / prop settings are ?

I'm pretty sure you set the Thrust levers to idle once descent begins and then you adjust the levers accordingly depending on your target speed.

Descent by IAS is the best and less hassle and secure usually regarding overspeed or stall-low speed, adjusting your descend-climb rate if desired with more or less throttle.

Not sure that's SOP but that's how I've generally operated all my turboprops, IAS hold for climb and descent and adjust thrust to get desired rate of descent. Quite a few only had advisory VNAV (if they had VNAV at all) so it wasn't coupled to the AP. If there is a VNAV calculation I usually specify a slightly steeper descent than the default to allow the engines to almost idle as I believe this is more fuel efficient.

The ATRs VNAV seems quite a bit more sophisticated than what I've used on Universal UNS-1 and Honeywell GNS-XLS systems so I should probably let the aircraft manage things... but the lack of autothrottle means I will need to keep a closer eye on the ASI!

Edited May 11, 20233 yr by ckyliu

I can only recommend to check the videos in YouTube from "737NG Driver". It contains a complete set of chapters dedicated to flying the ATR as professional pilots should do, according to the FCOM (Flight Crew Operating Manuals).

Looks like your at the service ceiling and very slow as well??. I imagine it wants you to put some power back into it and speed up so your not sitting on the top of the yellow area of the speed tape.

15 hours ago, dresoccer4 said:

new to the ATR and ran into an issue. when setting a lower altitude, enabling VS mode, and rolling the nose up/down wheel to -500fpm, the plane begins to descend for about 5 seconds, but then “MONITOR SPEED” appears on the PFD and the entire descent is cancelled.

I can not get the AP to continue my descent at all. Anyone know why this is happening and how to circumvent it?

You're about to stall... that's why monitor speed is shown and autopilot halted all actions.

17 hours ago, dresoccer4 said:

new to the ATR and ran into an issue. when setting a lower altitude, enabling VS mode, and rolling the nose up/down wheel to -500fpm, the plane begins to descend for about 5 seconds, but then “MONITOR SPEED” appears on the PFD and the entire descent is cancelled.

I can not get the AP to continue my descent at all. Anyone know why this is happening and how to circumvent it?

It's trying not to kill you. You're at the yellow band, it's a speed protection. Put a little throttle into it, descend at 210 or 240 kts.

19 hours ago, dresoccer4 said:

new to the ATR and ran into an issue. when setting a lower altitude, enabling VS mode, and rolling the nose up/down wheel to -500fpm, the plane begins to descend for about 5 seconds, but then “MONITOR SPEED” appears on the PFD and the entire descent is cancelled.

I can not get the AP to continue my descent at all. Anyone know why this is happening and how to circumvent it?

As you pass your TOD marker hit the VNAV button, this will put you in the correct descent mode. Monitor speed means just that, watch your speed in descent ( I normally pull the throttles back to 50%) also you are nowhere near stall speed. I do advise to watch 737 Drivers videos and also the MSFS ATR videos here:-

and here:-

 

thanks for all the responses everyone!

for those saying it's to help with speed, when i begin the -500fpm descent my speed begins to increase (which is what the consensus says should be happening). But then the descent is cut off and the plane levels out, thus lowers my speed again. It seems more like the plane is trying to keep me slow if anything. I was actually trying to descend in order to pick up air speed since I was way over the ceiling and throttle was at full notch. 

I'm thinking now I just confused the AP since I was flying out of the normal envelope

1 hour ago, dresoccer4 said:

thanks for all the responses everyone!

for those saying it's to help with speed, when i begin the -500fpm descent my speed begins to increase (which is what the consensus says should be happening). But then the descent is cut off and the plane levels out, thus lowers my speed again. It seems more like the plane is trying to keep me slow if anything. I was actually trying to descend in order to pick up air speed since I was way over the ceiling and throttle was at full notch. 

I'm thinking now I just confused the AP since I was flying out of the normal envelope

Well that's how it works on an airplane without an autothrottle, have to keep up with the situation. That said a turboprop is very easy to keep on the desired speed, it's almost as if the throttle levers were "speed levers".

6 hours ago, Fiorentoni said:

You're about to stall...

oh come on. Far from it. Just increase power and he's fine.

"About to stall" is in my book, when you can feel the aerodynamic buffeting (and most likely the stick pusher since it's fed by AoA data) and perform a specific recovery maneuver (whatever that is in the ATR)

Edited May 11, 20233 yr by SAS443

29 minutes ago, SAS443 said:

oh come on. Far from it. Just increase power and he's fine.

"About to stall" is in my book, when you can feel the aerodynamic buffeting (and most likely the stick pusher since it's fed by AoA data) and perform a specific recovery maneuver (whatever that is in the ATR)

You're right, I was a over-dramatizing a bit 🙂

On 5/11/2023 at 3:39 PM, Fiorentoni said:

Well that's how it works on an airplane without an autothrottle, have to keep up with the situation. That said a turboprop is very easy to keep on the desired speed, it's almost as if the throttle levers were "speed levers".

that's how what works? stopping me from increasing speed? using