Bumpy A346?

[Nigel PAX]

I had my first trip on a VS A346 this week, sitting in the front row. I was struck by how bumpy it was while taxiiing, and when we hit turbulence (there seemed to be some yawing as well, though it's hard to be sure with Virgin's angled seat beds). It was smooth and quiet at other times. I've flown quite often in the first few rows of 747s and don't recall a similar rough ride; the A343 also seems much smoother.
I was wondering if the bumpiness was in some way related to its extreme length? I realise that I was sitting a long way from the CG, but this must be equally true in the nose of a 747. And, if the distance from the CG is the factor, it must be even worse in the flight deck. Is this the case?

[captain cumulonimbus]

Hi Good sir/madam.

You are not incorrect.Many pilots have complained of suffering motion sickness in A346 cockpits after having spent years on the B744s etc.Also,there is a noticeable amount of "dutch roll" (simultaneous yawing and rolling) on the 346s.I have heard (though it is definitely second hand info) that there are concerns regarding the structural integrity of the front sections of the 346s too as there is such a lot of flexing and this is believed to obviously lead to increases in stresses to the adhesive-joined body plates.

Try posting your query in the African Aviation Forum for SAA pilots to have their say...i'm sure you'll get a great deal of first hand info as i know a number of the guys on there fly 346s.

Cheers,Cb

[vapilot2004]

Didn't Airbus update the Rudder control software to assist with minimizing the 'dutch roll' effect on the A346 ?

[Nigel PAX]

I think they did update the software, but that wouldn't explain the bumpy taxi. In any case, even in the front row, I was sitting just behind the nose wheel; in the nose of a 744, I would be sitting well ahead of the wheel, and yet the ride is much smoother.

[055166k]

Bumps on the ground may be caused by the aircraft taxying over the slightly raised centre-line lighting. The "bus" has both nose-wheel and body undercarriage whereas the "74" only has the nose-wheels on the centre-line.
This is a complete guess as I know little about either, perhaps a pilot can offer some explanation on whether that may be a factor.
Interesting fact......the old Trident had an offset nose-wheel which retracted sideways......any Trident pilots out there to say if they avoided the problem?

[Nigel PAX]

Actually, all A340s have a centre main bogie, with either two or four wheels, depending on model. So do some other aircraft, such as the DC10-30. I've not noticed a bumpy taxi with any of those.

In any case, given that I was sitting just behind the nose gear, I doubt that I'd have noticed any bumps from the main gear -- the A346 is so long that the main gear is almost a time zone behind you. I was therefore wondering if the A346 has the equivalent of stiffer suspension at the front (higher oleo pressure?). As a theory, it may be that there's more weight on the front gear with the long 346 than with the shorter 343.