Dash 8 400 Cabin Noise

[SLF3]

Have not been on this type more than a dozen times, and generally find the cabin very noisy: particularly if the plane is a bit long in the tooth. Have had some spectacular flights on them in Northern Norway, though.

Based on jet experience I generally look for seats over the wing or forward, since they tend to be quieter and the ride is better. The back row of a 737 is my pet hate.

However, recently took a flight in the back row (you look out the window at the exhaust) of a Dash 8 and was surprised to find it relatively quiet and vibration free. On the way back was just forward of the prop (though in the cabin!) and landed both shaken and stirred.

So my question: are turbo propos generally quieter / more comfortable at the back or was I just lucky? Where is the quietest place to sit on a Dash 8 400?

[Rob Courtney]

I fly this type quite a lot and find the rear of the cabin much quieter. It was the same on the earlier series aircraft as well and would think its pretty standard on all props especially high wing models.

Compared to the old ATP they are much quieter wherever you sit though.

I used to do the shuttle run down to LGW every week some years ago and discovered that although noisy the back seats of the old 737s did have one big advantage, you always got your breakfast first.

[longer ron]

Just recently flown a couple of trips on these a/c - definitely quieter near the back,as far away from the props as possible :)
I have always done this on prop a/c as I hate the noise/vibration further fwd.

[Johnny F@rt Pants]

Always alway always go towards the rear on a turbo-prop. When I used to operate the ATP, on positioning sectors, the engineers always used to nab the back seats before the positioning crews got there, they knew!!

[fa2fi]

I really like them. I used to fly hour long hops and comfort was similar to the A319/320. It is a bit louder but I always listen to music anyway so it wasn't an issue and I was always surprised at how quiet it was. I am a fan and flyBE seem to be extremely happy as Saad was at Farnborough recently singing their praises.

Ex UK the Q400 is used on some fairly long hops and I wouldn't hesitate to fly them.

Speaking of ATPs - I loved them. They were the first aircraft I flew in and I fell in love with flying because of them. Both in the air and on the ground they have such a unique sound.

I really want to try catch one for one last time with NextJet in Sweden.

[Midland 331]

First class was at the back on big piston props, IIRC.

The back seats on a BA 757 were always an interesting ride on an approach with a strong crosswind component, as the fuselage used to "wag" quite noticeably. Looking down the aisle right to the front (with the flight deck door open occasionally) it actually was visible!

[Local Variation]

Flew on a Dash 8 this evening.

You can feel the vibrations through the wall panels. However, it's the noise that does you. In the air it's ok. On the ground, much less so.

Today, whilst taxiing, it was as if you could hear two separate noises, with different frequencies. I was in row 15, adjacent the starboard engine. Not the first time I've noticed this on this aircraft.

The overhead lockers are also very small, depth wise. Good job the flight was only 50 minutes.

Despite all this, they do appear a good fit for the job.

Seem to recall a similar discussion on here some years ago that mentioned some in-built white noise?

[TURIN]

I think the Q400 has an anti-noise system built in that sends sounds through the cabin speakers that are opposite to the noise from the engines/props. Bit like the ANR headsets used by the drivers.

[purplehelmet]

I flew on two saab 2000's last week, had to check I still had all my fillings in place after we landed..

[Midland 331]

The Q400 is astonishingly frugal, so I understand.

This is why so unlikely city pairs are served by them. It's average break-even load is normally half it's seating capacity on most sectors.

The down-side? Some noise from those 15ft props. For me, it's the closest to "real aeroplane" that a modern aircraft gets. But I don't drive one.

[Tu.114]

Turin, there is an active noise reduction installed indeed. It has microphones scattered all through the cabin (usually located behind those small brass rings) that pick up the noise at their location, then a vibration of the same frequency, albeit with negative amplitude, is issued. This does not make the cabin very quiet, especially around the propellers, but it does reduce the overall noise level noticeably. If for some reason the system is set to "pause" in flight, the propeller hum is still there, but more so than before. It does not work equally well on all aircraft; among our fleet, some are much quieter in the cabin than others.

I do agree with what has been written several times already: if at all possible, take a seat in the last few rows. The propellers are still audible back there, as is a bit of exhaust airflow, but overall, those are the quietest seats in the aircraft by far. The reason why the business class is not back there is simply the passengers having become accustomed to finding the expensive seats in the front of the aircraft. There even was a survey some years ago to find out the preferences of the passengers: Business Class in the front, between the propellers and far from the galley, or rather in the back, close to the galley and much quieter than in the front? Somewhat surprisingly, a majority of passengers preferred the former, valuing seat 1A and a good rattling of their dentures higher than a calm and serene flight on 21F and boarding via the servants entry in the back. So be it then, said the company, and left everything as it is now.

Some numbers about the DH8-400. It can be operated nearly like a jet with a TAS of around 360kts at FL200 (a bit depending on temperature), burning slightly more than a ton/hour. Or it can be flown like an ATR or DH8-300 at much reduced power settings, resulting in around 300kts TAS and a hourly burn of a bit less than 900kg. If You will, the DH8D does the job of a Fokker 70 with half the fuel and lower ATC costs.

[darkbarly]

Q400 = actuators fitted to fuselage frames alter the cabin internal diameter by thousands of an inch to counteract pressue pulses created by both sixbladed prop tips rotating at 850,900 or 1020 rpm. Pickup is electronic and acoustic. Reduces by a few db. Very noticeable when an actuator goes out of sync.

No anti noise through speakers.

Prop rpm can be electronically maintained at 850 on approach for earth dwellers comfort too.

Best solution for noise is to fly on the high bypass version of the Q4 = C series.

[SLF3]

Thanks for the replies. Down the back for Mrs Morris' little boy, methinks.

The downside is 43 people in front of you to get off, but I'll take the hit.

[Tu.114]

Not necessarily. Depending on the setup bought by the airline You travel on, there may well be a rear airstair installed on the aircraft. It is stowed behind the door (viewed in direction of flight, facing the door from the inside, it is on the right) and can be pulled and folded out if desired.

This stair speeds up boarding and disembarkation noticeably but is not exactly popular with the cabin attendants staffing the exit: it is rather heavy and not that easy to retract and restow after use. Also, some airfields do not like its use, typically because they have no equipment or staff to keep the passengers from wandering below the wing and through the propeller arc.

We use this stair every time we are allowed to and if the passenger number is above 40. With less passengers, experience shows that the rear stair is usually ignored. Most passengers seem to prefer standing out in the rain at the forward entry to quickly boarding a well tempered cabin in the back even with the rear flight attendant waving, calling or using whatever other means to attract their attention...