CRJ High Altitude Stickshaker

[pelmet]

A friend of mine recently checked out on a CRJ in the US. He is making big bucks. Anyways, he mentioned that there is no autothrottle. Definitely want to monitor speed more closely in aircraft with no autothrottle after a significant power change....

C-GJZT, a Jazz Aviation LP CRJ900 was conducting flight AC8387 from Toronto/Lester B.
Pearson Intl. (CYYZ), ON to Saskatoon/John G. Diefenbaker Intl. (CYXE), SK. During cruise at
FL360 in the vicinity of Sault Ste Marie Airport (CYAM), ON, the flight crew reduced thrust to
achieve cruise speed. Shortly afterwards following the adjustment, the low-speed cue and angle of
attack parameters were met resulting in momentarily stick shaker and stick pusher to activate. The
crew reacted in a timely manner with minimal loss of altitude and continued to destination and
landed with without further incident.

[flyer 1492]

Flew the CRJ's for 13 years, never had a problem with low or high-speed warnings. You have to remain vigilant during the flight.

[YHZCL]

Flew the CRJ's for 13 years, never had a problem with low or high-speed warnings. You have to remain vigilant during the flight.

Agreed.

Find this weird given the location and altitude. Had they been higher, over the rocks in some strong mountain wave and had poor throttle management it would be more understandable.

[Eric Janson]

C-GJZT, a Jazz Aviation LP CRJ900 was conducting flight AC8387 from Toronto/Lester B.
Pearson Intl. (CYYZ), ON to Saskatoon/John G. Diefenbaker Intl. (CYXE), SK. During cruise at
FL360 in the vicinity of Sault Ste Marie Airport (CYAM), ON, the flight crew reduced thrust to
achieve cruise speed. Shortly afterwards following the adjustment, the low-speed cue and angle of
attack parameters were met resulting in momentarily stick shaker and stick pusher to activate. The
crew reacted in a timely manner with minimal loss of altitude and continued to destination and
landed with without further incident.

A good review:- https://www.faa.gov/other_visit/aviatio ... ations.pdf

Difficult to comment on the above incident without more details.

One thing I am seeing is that computer flightplans tend to put the cruise altitude very close to the maximum altitude - nothing wrong with that but it may not always be desirable. If your aircraft is heavier than what the flightplan is calculated for is one obvious example.

Too many people see the computer flightplan as something to be blindly followed - I look at it as a starting point.

[pelmet]

C-GJZT, a Jazz Aviation LP CRJ900 was conducting flight AC8387 from Toronto/Lester B.
Pearson Intl. (CYYZ), ON to Saskatoon/John G. Diefenbaker Intl. (CYXE), SK. During cruise at
FL360 in the vicinity of Sault Ste Marie Airport (CYAM), ON, the flight crew reduced thrust to
achieve cruise speed. Shortly afterwards following the adjustment, the low-speed cue and angle of
attack parameters were met resulting in momentarily stick shaker and stick pusher to activate. The
crew reacted in a timely manner with minimal loss of altitude and continued to destination and
landed with without further incident.

A good review:- https://www.faa.gov/other_visit/aviatio ... ations.pdf

Difficult to comment on the above incident without more details.

One thing I am seeing is that computer flightplans tend to put the cruise altitude very close to the maximum altitude - nothing wrong with that but it may not always be desirable. If your aircraft is heavier than what the flightplan is calculated for is one obvious example.

Too many people see the computer flighplan as something to be blindly followed - I look at it as a starting point.

Good point. When one gets their final weight for the flight, they might want to check it with the flight plan as there could be significant differences from the flight plan meaning you may want a different altitude than what was planned.

Of course unlike the old airliners, the FMC on more modern airliners is giving an altitude recommendation to make it easy for you but a heavier than anticipated load could affect ability to meet ATC altitude requirements/restrictions, sometimes quite far down the road in some parts of the world.

Obviously the heavier than expected will usually be the most problematic. One should ask themselves how a significantly increased weight will affect them on the flight. Weight limitations, cruise altitude, fuel burn, landing destination with a short runway.