Dutch Roll on the Embraer 145

[2Donkeys]

Flew as pax for the first time on the 145 a couple of days ago. Despite reasonably calm conditions, there was a noticeable Dutch Roll throughout. So was I lucky enough to get on an aircraft with a failed yaw damper, or is this typical for the type?

[henry crun]

I cannot answer your question 2donkeys but will you allow me to add one to yours if you catch the attention of the experts.

Why is it called Dutch Roll, why not
Italian, German, or some other nation Roll ?

[Genghis the Engineer]

I know very little about the EM145, but there are two common explanations to the name Dutch Roll.

The most common is that it is the motion described by an ice skater on a frozen Dutch Canal.

The less common, but which I prefer, is that it's the motion seen on an old Dutch Merchantman (sailing ship), which were round bottomed with little keel, and thus tended to constantly roll and yaw as they sailed.

G

[compressor stall]

Saw a similar motion from the buttocks of a scantily clad Dutch girl walking in front of me on the Esplanade in Cairns this afternoon.....

[henry crun]

Thanks Genghis, logic tells me that your answer is the correct one but my imagination prefers that of Compressor stall :)

[moggie]

I confess that I know very little of the Embraer but I do recall seeing a flight test in Flight International which remarked on the "requirement to use rudder to balance low speed turns". now, this sounds to me like a) no yaw damper, b) poor yaw damper c) dodgy design elsewhere.

Yaw damper helps to balance turns by countering slip (applying top rudder for you) allowing the rudder pedals to become little more than footrests in normal use.

[boris]

The auto pilot is not too smart in its ability to follow the required or computed heading which results in constant, irritating little heading corrections which only SEEM a bit like like dutch roll. Modification action is under way to cure this.
For your interest, the actual dutch roll characteristics of the 145 are benign.

[PAXboy]

Is this characteristic then true of it's baby sister the 135? And, possibly, other varaiants?

[OzExpat]

Stallie... you PPeRVe! Didja have a thoughtie for me too? :D

[renard]

The firsat time I flew as a passenger on a EMB145, i noticed the same thing. I've been flying them from the front for about 3 months now and don't notice it at all.
What I was told in groundschool/conversion training was that it was caused by the aircraft being very slightly out of balance.
The aircraft yaws slightly and the only wa the autopilot can correct is by using the ailerons.
We are flying at high altitudes and M0.76, but only have outboard ailerons, no high speed inboard ailerons. The ailerons are either not stiff enough or they cause the whole wing to twist slightly and then you get the roll you experienced.

Solution - keep the ball in the middle!

[erikv]

Sorry to modify your subject here, but I've noticed a very strong sensation of tunnel vision during, even straight and level flight, on each of the occasions I flew the EMB145.
I must admit I was sitting near the rear end of the plane...

Did anyone experience the same?

[ 17 November 2001: Message edited by: erikv ]

[Cardinal]

Isn't tunnel vision one of the symptoms of Hypoxia? You didn't, by chance, have blue fingernails and a sense of euphoria, did you?