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Wannabe Flyer
2nd Nov 2009, 06:32
On a recent trip on a brand new 330-200 I noticed on the IFE screen the speed reading at 250 mph when the wheels came down. Is this is the normal speed for wheels down? We landed about 2 minutes later. The noise of the wheels coming down were relatively noisy (louder than other aircraft i flew on a few days earlier) but not too loud to startle anyone

On the outbound journey a few days later the aircraft did a rapid descent after holding a while and this time when the wheels came out there was a lot of noise and very solid thunks followed by some banging noise of a longer duration. Unfortunately I was not on the screen that would give the speed. I looked around and the noise seem to have startled a lot of people. We landed barely 45 seconds later in what seemed was a higher speed than what is normal. This was followed by rapid braking which was then released and a very long roll out.

In the past I have noticed this sound on wheels down in 330 but it is absent in the 320 or 737

Rainboe
2nd Nov 2009, 07:55
One of the bigger problems for pilots these days are passengers who sit in 21J knowing how to fly the plane better than they do. Your impressions are mistaken- the gear would not come down 45 seconds before landing, the gear even on a 747 makes a noise, it certainly does on a 737, and passengers know best how much braking should be applied! The 'rapid descent after holding awhile'....that would be under the control of ATC. Do you think everybody wants your impressions of your flight and what you thought happened?

strake
2nd Nov 2009, 07:58
Do you think everybody wants your impressions of your flight and what you thought happened?

Only so we can have the pleasure of anticipating your reply...:E

Espada III
2nd Nov 2009, 08:33
I have not been on this site for long, but I am starting to learn about different people!!

Those of us who are a little technically minded but for whatever reason did not become pilots are permitted to ask reasonable questions about flying aircraft and may know a little about the technical details. What we would like on this particular section (this is the SLF section you know!) is some informed and pleasant advice about such matters, not - we are the masters of the universe; leave us alone.

If I treated my clients like that, I would have no business and therefore no money to spend flying a family of five several times a year on holiday.

So, please Mr Toxic, answer the question asked in a polite and informative manner.

Wannabe Flyer
2nd Nov 2009, 09:49
Rainboe,

Just a question asked tapping into vast knowledge of pilots. Therefore this was asked in the SLF section.

As far as the noise is concerned I have been flying as an SLF for over 20 years now and do realize the sound made in the passenger cabin is louder than normal or not. I am assuming you have done most of your flying up front so maybe in this area a veteran SLF does have some experience. I still stand by that the noise was way above what I have experienced and was wondering if gear lowered at 250 mph plus could be the cause (note on the IFE sector inbound I saw 250 mph on the screens when the noise of gear coming down started. Still ask this question and hope you can answer it.

The only reason I knew gear came down 45 seconds before landing is because on the IFE on the top left they had a countdown on the program I was watching and from the time the noise ended of the wheels down till we touched down was 45 seconds.

Staying on sound I was in row 23 G both times and I must say the 330 is the quitest plane I have been on a long time considering my proximity to the engines.

I love twins
2nd Nov 2009, 11:51
If the crew extended the landing gear at a higher speed than "normal" then yes of course it would be louder in the cabin especially as the gear doors open. Not sure if the 250mph they give on your IFE is IAS,TAS,GS and i'm certainly not sure if that information displayed is correct/current.

If they did extend earlier than usual then it may be because they had a strong tailwind, were struggling to get below vfe next, were getting significantly high on profile, had been cut in tight, continue ad nauseum...

On another note, Gear down 45 seconds before touchdown seems incredibly late, I would question your timing on that, given its source.

On the type I fly we extend gear at around 5nm (allowing for how deceleration is going/winds etc). If you average out the speed from then its around 120kts GS, so you'd be looking at around 2 minutes between gear down and touch down.

As you can see from that logic 45 seconds would equate to 1.5nm out or around 500ft AGL. They would not meet the stable criteria for landing and a go around would be flown.

Please excuse my figures if slightly out, i base them on A320, but imagine the A330 wouldn't be a million miles away!

Captain_djaffar
2nd Nov 2009, 12:43
screen the speed reading at 250 mph


I presume it is the true airspeed.
If yes, it is normal.

Restrictions ( due to metal fatigue, stresses etc...) on the landing gear are hedged based on the Indicated Airspeed.

True airspeed may vary largely from what it is shown on the indicated airspeed indicator. ( due to high altitude, wind etc...)



Correction: It tends indeed to be the ground speed. Words misplacement.
[Sub all TAS with ground speed].

raffele
2nd Nov 2009, 12:51
screen the speed reading at 250 mph
I presume it is the true airspeed.

Doesn't it tend to be groundspeed? I'm sure I've seen on a few moving map channels it showing it as groundspeed...

DTVOne
2nd Nov 2009, 22:37
Doesn't it tend to be groundspeed? I'm sure I've seen on a few moving map channels it showing it as groundspeed...
Normally ground speed, headwind bad, tailwind good, get home early.

DTVOne
2nd Nov 2009, 22:42
In the past I have noticed this sound on wheels down in 330 but it is absent in the 320 or 737The perception of the flight and noises heard really depends very much on where you sit.

Wannabe Flyer
3rd Nov 2009, 04:23
Most in sightful. Will try and choose a different seat on my next trip and revert if the sounds are different. The 330 seems to be increasingly popular in the region I am flying in so the chances are good for me to make another determination. This time will be prepared with stopwatch :cool:

Rainboe
3rd Nov 2009, 09:16
What you took to be wheels down noise was far more likely to be engine power up after reducing speed to final approach speed. As said, sitting in a different cabin section, just a few rows away even, your noise perception will be totally different.

Espada III
3rd Nov 2009, 13:41
Must admit that the A330 I sat in a few weeks ago (in front of the engines but in economy) was the quietest aircraft I have been in for a long time.

Up front on a 747 was not as quiet and the noise made when the wheels came up or went down was very clunky.

NRU74
3rd Nov 2009, 20:19
Strake
Only so we can have the pleasure of anticipating your reply...http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/evil.gifBlimey....he's like a pussy cat now !

TightSlot
4th Nov 2009, 08:23
Roll 'em on their backs and tickle their tummies - never fails

strake
4th Nov 2009, 08:41
Strake

Quote:
Only so we can have the pleasure of anticipating your reply...

Blimey....he's like a pussy cat now !

Methinks Tightslot has returned from a trip and is doing a little "housekeeping" with a number of posts and posters...:ooh:

Wannabe Flyer
4th Nov 2009, 09:14
What you took to be wheels down noise was far more likely to be engine power up after reducing speed to final approach speed.


Sound heard was an extended moter whirring, doors opening sound of the doors in slip stream (rushing wind) then a loud thunk including the floor shuddering enough to cause my IFE screen to tilt and then moters again and the sound of doors closing with the sound of the slipstream subsiding.

While not even close to your flying experience, I did here the sound of the engines a short while later...... they were more uniform and had the familiar spooling up sound.

CPP2009
4th Nov 2009, 09:59
I must admit that gear down on an A330/340 does make an awful noise compared to other aircraft. I'm always startled by it.

Final 3 Greens
4th Nov 2009, 14:23
I took two flights on a 330 this week and made a point of sitting over the wing.

CPP2009 calls it right, it does make a fearsome racket compared to other aircraft.

However, as much as one can judge from row 15, the approach and landing was normal.

I like the 330, very quiet in the cruise.