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-   -   Which part of the cabin for the smoothest ride? (https://www.pprune.org/passengers-slf-self-loading-freight/446441-part-cabin-smoothest-ride.html)

ony 28th Mar 2011 09:22

I wonder if the ride would feel as rough in the front of the cabin as in the rear?

dClbydalpha 29th Mar 2011 06:44

Firstly comfort is a very subjective thing, based on noise, heat, light, vibration and movement, so there is no one answer. Noise tends to be worse nearer the engines. But most people are disturbed by movement.

An aircraft will tend to rotate about its centre of gravity. Any force not applied through the CG will create a rotation as well as a displacement. The position of the CG is controlled carefully to ensure that the aircraft is balanced. The two large forces on an aircraft are lift and weight, for stability reasons it is good to keep them fairly close together, and so the CG is placed near the wings. The further away from the CG you are, either forward or rearward, the more pronounced any movement due to rotation is. Most people find sitting forward to be smoother, and this is due to the change in motion experienced due to displacement and rotation.

If you see an aircraft taking off, as it rolls down the runway it gets to a point where it rotates and then takes off. When it rotates the nose goes up and the tail goes down as the aircraft climbs overall. For those in front of the CG they will feel themselves lifted up first by the rotation and then by the climbing of the aircraft. In the rear they will feel themselves descend first due to the rotation and then climb. So although, everybody is lifted overall, those in the front experience it differently to those in the back. This change from down to up can be quite disturbing to the equilibrium. In my understanding this is why it is better to sit forward than rearward, but to minimise this effect get as close to the wings as possible.

Mark in CA 29th Mar 2011 11:45

"Smoothest" will always be over the wings because of location of CG, about which roll, pitch and yaw occur. The further you are from the CG, the more pronounced the movement about these axes. Vertical and horizontal displacements affect the whole plane equally. Forward of the wings is generally quieter. Conversely, aft of the wings is generally more noisy.

airsupport 31st Mar 2011 22:02


"Smoothest" will always be over the wings because of location of CG, about which roll, pitch and yaw occur. The further you are from the CG, the more pronounced the movement about these axes. Vertical and horizontal displacements affect the whole plane equally. Forward of the wings is generally quieter. Conversely, aft of the wings is generally more noisy.
Yes, as I said earlier too, the smoothest ride MUST BE over the wings, it is just simple mechanics/engineering. :ok:

That well may NOT be the quietest, most comfortable, safest etc but that is NOT what was asked. :ok:

SNS3Guppy 1st Apr 2011 11:20


You USN flyers never had a sense of humour.
Which USN flyers would those be?

Not a crowd of which I'm a part. I work elsewhere.

PAXboy 1st Apr 2011 13:15

I recall being on a ship once (the old style boats of the Union-Castle line) and my cabin was near the back. When the ship was in heavy weather, I could feel the cabin: Sink; move to the left; rise; move to the right; and then sink again as the pitching and rolling continued. NOT GOOD!

Mad Monk 3rd Apr 2011 18:49

I was on the old Union Castle/SA Windsor Castle, Southampton to Cape Town way back in '77. Cabin was well to the forward, outer starboard on/under the surface.
Felt pitch and roll well, despite the stabilisers. Minimal time spent in the 4 berth cabin, only 3 of us to start and the God Botherer some how disappeared after night one.
Great 13 day trip.

First airplane was a Viscount between Bulawayo and Wankie, aft of the wings. A bounce was felt in flight and those wings did flap about, the seats behind the cabin bulkhead were pointing backwards, a lá Military.

After similar flights as a younger person, I do not care. Peace & quiet is want I require, not self important, noisy or agressive SLF.

clareprop 3rd Apr 2011 19:56

I really don't understand the question...

In my G-IV, should I find some level of discomfort at the front, I move to the back...or any point in between that takes my fancy. If the problem continues to annoy, a bottle of Krug '64 often distracts....
If neither of these simple steps improve the situation, then it's obviously a crew issue and they should be dismissed upon landing.

malcolmf 3rd Apr 2011 23:28

In turbulence, the natural movement of an aircraft is to go nose down in an updraft, and nose down in a downdraft. This is because the airstream vector moves down and up, producing more or less lift. The aircraft then rotates about the nose. The same applies in the vertical axis. It is complicated by the reaction of the pilot, autopilot or yaw damper to the gust, and also the inherent stability of the aircraft, which in turn is dependent on the position of the Centre of Gravity.
I would say then that the smoothest ride is at the front. It is also why it is difficult to tell exactly how bumpy it is in the back from the Flight Deck.

Tetsuo 10th Apr 2011 18:09

From slf experience I can only tell, further to the front is always better. Less noise, less shaking from turbulance etc.

Frognal 10th Apr 2011 19:50

The front is smoother, because you have been sedated by the hospitality in the premium classes.

Manchikeri 10th Apr 2011 20:37

MalcolmF
 

In turbulence, the natural movement of an aircraft is to go nose down in an updraft, and nose down in a downdraft.
Are you quite sure about that, MalcolmF?

PAXboy 10th Apr 2011 22:39

Mad Monk

Union Castle/SA Windsor Castle, Southampton to Cape Town way back in '77.
It was the RMS Windsor Castle of (by that time) the Union-Castle Safmarine company. She was the flagship. I was on her in January '66 from CPT to SOU and am currently in CPT, leaving for LHR today and the journey will take 12 hours, rather than 12 days. But one of the reasons that the line folded!

She was a lovely ship and now back to the thread ...

Smoketrails 11th Apr 2011 10:09

After recent experiences, nothing beats upstairs on the B744!

PAXboy 14th Apr 2011 23:41

This week, I was on a VS A346 CPT~LHR, which is 12 hours. Seated in 21A, a PE seat just at the leading edge of the wing.

Overall, it was very comfortable. Interestingly, I could see the slight rolling motion but could not feel it. The roll was small but continued for much of the flight and was seen by the wing against distant clouds.

Noise was, naturally, louder at this point as the #2 was right outside. I also found that my Philips Noise Cancelling headphones were not as effective against the background noise - as they had been on the outbound, which was a 744.

Piltdown Man 26th Apr 2011 21:23

The smoothest ride would be obtained of over the wings and optimally I'd go about 1/3rd back from the leading edge for the perfect ride. This wouldn't necessarily be the nicest ride as you'd be in the the cheap seats with a tighter pitch. You also be over various aircraft services which would make a noise when operating and then there's those sitting around you... So given the choice (and the cash), I'd sit towards the rear of First/Business/Upper/Alan Bennett Class.

PM

ony 27th Apr 2011 12:50

Good point about the noise over the wings from various aircraft services. I realise that noise is also an important comfort factor.

The reason for my OP is that we're going on a one-class charter holiday flight, where we can pre-book our seats (against a modest fee, of course), and I now have a better idea where in the cabin to book.

But out of curiosity, given that the ride is smoothest over the wings and rougher in the rear of the cabin, would the ride be equally rough in the front as in the rear if we make the rough assumption that the wings are midway down the fuselage?

Dairyground 30th Apr 2011 22:15


But out of curiosity, given that the ride is smoothest over the wings and rougher in the rear of the cabin, would the ride be equally rough in the front as in the rear if we make the rough assumption that the wings are midway down the fuselage?
That would probably be true if the fuselage were rigid. However I have always thought that the effects of rudder and elevators, combined with the (small amount of) flexibility of the fuselage made the back end move around more than the front end.

PAXboy 30th Apr 2011 22:27

I recall reading in here, on more than one occasion when this subject has been discussed, that pilots say, 'When it's bouncy for us - it's REALLY bouncy for the pax.'

This indicates that the nose gets less bounce but also, I think, that the FC are more used to bounce! :yuk:

TightSlot 1st May 2011 08:28

When assessing the need for Seatbelt Signs OFF/ON and whether the FA's should be strapped in, pilots often contact the back of the aircraft to check how things are. The rear is always the toughest ride, especially on longer aircraft. Two days ago, I asked for my crew to be strapped in and galley secured at the rear two doors, whereas the forward doors/galleys/crew continued (with care).


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