Airport Noise Related to - Flight Path Just After Takeoff - Takeoffs Now Radically Increasing?

[BaronOfThunder]

Yeah.

Also, I like taking off to the North.

Didn't get this lucky the last four departures though, all to the South. (Last one was three weeks ago.)

1.jpg

Taking off to the North is obviously very beautiful when one is inside and not on the ground outside. I cannot argue with this logic.

PS: Again, nice photography. I posted your fireworks photos to another site, without attribution.

Edited January 4, 2016 by BaronOfThunder

[harrry]

Sorry, but it's not that simple.

Aircraft need to be landing & taking-off into the wind, the wind-speed reduces the effective ground-speed, while the air-speed over the wings is higher, to provide lift. Taking-off with a strong tail-wind is not safe, and is not normally done !

So you cannot just land from-the-South, into a wind from-the-North, and then turn round and take-off to-the-South.

Just to clarify this. It is not a forced requirement to disallow departing with a tailwind as long as it doesn't exceed airport & aircraft maximums. For nearly all heavies the max tailwind component is 10kts (18kms/h). The average wind speed for Chiang Mai for a 12 month period is 3-4 kts (http://www.windfinder.com/windstatistics/chiang_mai).

This is a chart of the Beaufort scale of winds for the last year. Maximum shows is 3bft which means gentle breeze. The Beaufort scale though is based on physical effects as opposed to an absolute wind speed.

Beaufort CM.JPG

Also need to take into account the seasonal predominant wind directions which do a nearly 180 deg shift between the two primary seasons. Basically, the winds in Chiang Mai have minimal impact on departure/arrival direction choices, it will be predominantly traffic based.

Beaufort scale.....a system designed to judge the level of the winds so that english fishing boats could decide much sail to set how far to go to sea....

Strange to be using this in relation to things that go a hundred times faster.

Coments about the inversion layer which can occur over Chiangmai are possibly relevant. Is the nose more prevalant when there is haze and smoke trapped under it.

All told is an airport though. If you want planes you have to live with it. Having lived there I know how loud a fighter can be taking off....good thing they have not had a big airforce budget lately.

Edited January 4, 2016 by harrry

[arunsakda]

Maybe, the folks South of the airport have started a movement to avoid opposite direction departures and ATC is not approving

Is it fair those to the South should suffer all the Noise, both arrival and departure as is the OP wish?

[BaronOfThunder]

Maybe, the folks South of the airport have started a movement to avoid opposite direction departures and ATC is not approving

Is it fair those to the South should suffer all the Noise, both arrival and departure as is the OP wish?

I am not saying it is fair, of course, but I have stated that I do not know what is down there.

Someone mentioned the Pratt and Whitney engines, and this is the very best solution.

It is my understanding that the use of these engines would mean that noise from aircraft would be limited to INSIDE the airport grounds, which would be a happy development for all concerned, and will also mean that airports can be located INSIDE the city, which I think is also fantastic!

I also think that people South of the runway should move.

Just as people have been saying I should move, which I also agree with.

One thing is for sure, that the university should not be located under the path of huge jets which are taking off OR landing. This I DO know.

[Ricardo]

Based on a personal-sample of perhaps 60 departures from CNX over a decade, some 25% (perhaps 15 or so) took off from Runway-36 towards the South, but I've never landed on Runway-36 from the North, in all my arrivals during that time.

Which suggests that the authorities do try to reduce the noise over the city, when they can, FWIW.

Glad you got a better night's sleep, anyway !

[MESmith]

Having lived there I know how loud a fighter can be taking off....good thing they have not had a big airforce budget lately.

Thai airforce fighters are very quiet, compared to the noise a fully laden Tornado on its way to bomb Iraqi forces in Kuwait made, when I was at Dhahran airport back in 1991.

[harrry]

Having lived there I know how loud a fighter can be taking off....good thing they have not had a big airforce budget lately.

Thai airforce fighters are very quiet, compared to the noise a fully laden Tornado on its way to bomb Iraqi forces in Kuwait made, when I was at Dhahran airport back in 1991.

There were lots of noisy ones here about 45 years ago when there was no war in Laos.

[taotoo]

I have not seen even one aircraft take off toward the south, since I started monitoring using the FR24 software on my phone and on my browser.

I've noticed the odd south-bound flight take off to the south at about 11pm or so - maybe they do it when there aren't many incoming flights around. Don't know how common this is.

And my question is: When will the majority of traffic revert to taking off to the South.

Don't know when they change I'm afraid. Could be days, could be months. Maybe now that the busy period is ending there will be a change, though I don't know what the reasons for changing the direction are. It only lasts for a while anyway, AFAIK over the course of a year the vast majority of take-offs are to the north.

[BaronOfThunder]

OK, Fine, however, One Thing I DO know is that the Boeing 777 is one of the worst noise offenders around here!

For example, one just flew over and I thought it might be the 747 400 that people here are talking about. But NO. It was the 777 heading to Bangkok, flight TG121.

Very, very noisy, and so I think that Boeing was putting over on us a huge piece of unfounded propaganda when they hyped this aircraft long ago.

I will not fly on one ever again!, simply because I do not think that they should be purchased for use by any airline.

Aircraft(B772)
Boeing 777-2D7

1TG121 / THA121

Thai Airways

Thai Airways

[BaronOfThunder]

Based on a personal-sample of perhaps 60 departures from CNX over a decade, some 25% (perhaps 15 or so) took off from Runway-36 towards the South, but I've never landed on Runway-36 from the North, in all my arrivals during that time.

Which suggests that the authorities do try to reduce the noise over the city, when they can, FWIW.

Glad you got a better night's sleep, anyway !

Thank you. However, it is my understanding that Runway-36 would not be the one used taking off to the South, since they would be flying South. Sill, good to know the information.

[Tywais]

Two aircraft just took off on the South runway just a few minutes from each other and a 3rd one taxing out for another South departure. THD151, NOK8303 and now AIQ102. I could tell by the sound while on my balcony in Mae Hia though I'm 1.4km west of the flight path.

[WinnieTheKhwai]

Two aircraft just took off on the South runway just a few minutes from each other and a 3rd one taxing out for another South departure. THD151, NOK8303 and now AIQ102. I could tell by the sound while on my balcony in Mae Hia though I'm 1.4km west of the flight path.

Yup.

OK, Fine, however, One Thing I DO know is that the Boeing 777 is one of the worst noise offenders around here!

For example, one just flew over and I thought it might be the 747 400 that people here are talking about. But NO. It was the 777 heading to Bangkok, flight TG121.

Very, very noisy, and so I think that Boeing was putting over on us a huge piece of unfounded propaganda when they hyped this aircraft long ago.

I will not fly on one ever again!, simply because I do not think that they should be purchased for use by any airline.

Good luck getting to America in anything that's quieter.

Edited January 5, 2016 by WinnieTheKhwai

[Ricardo]

Based on a personal-sample of perhaps 60 departures from CNX over a decade, some 25% (perhaps 15 or so) took off from Runway-36 towards the South, but I've never landed on Runway-36 from the North, in all my arrivals during that time.

Which suggests that the authorities do try to reduce the noise over the city, when they can, FWIW.

Glad you got a better night's sleep, anyway !

Thank you. However, it is my understanding that Runway-36 would not be the one used taking off to the South, since they would be flying South. Sill, good to know the information.

I believe Runway-18 is the southern-end, normally used for landings from the South & take-offs towards to North, and Runway-36 is the northern-end of the same runway, used for landings (rare) approaching from the North over the west-of-town, and take-offs to the South ?

One might equally call it Runway-00, since 000-degrees & 360-degrees are the same thing, but airports generally seem to round off the numbers ?

Similarly Runway-09 and Runway-27 would be used to describe the opposite ends of an East-West runway.

https://en.wikipedia.org/wiki/Runway

Edited January 5, 2016 by Ricardo

[Ricardo]

<snip for brevity>

Good luck getting to America in anything that's quieter.

Thanks Winnie

That certainly shows vividly the progress being made in noise-reduction, as improvements are made in high-bypass engines & wings, the 'early bulge' in the B779X profile perhaps suggests that it gets airborne earlier, before the end of the runway ?

I used to work within view of the runway at London-Luton, and the noise from a departing B767-200 was no worse than some cranky old BAC-1-11, despite having more-than double the capacity !

But that's not much comfort, if you live under the flight-path, and close to the end of a runway.

[CNXBKKMAN]

Two aircraft just took off on the South runway just a few minutes from each other and a 3rd one taxing out for another South departure. THD151, NOK8303 and now AIQ102. I could tell by the sound while on my balcony in Mae Hia though I'm 1.4km west of the flight path.

Yup.

Capture.JPG

OK, Fine, however, One Thing I DO know is that the Boeing 777 is one of the worst noise offenders around here!

For example, one just flew over and I thought it might be the 747 400 that people here are talking about. But NO. It was the 777 heading to Bangkok, flight TG121.

Very, very noisy, and so I think that Boeing was putting over on us a huge piece of unfounded propaganda when they hyped this aircraft long ago.

I will not fly on one ever again!, simply because I do not think that they should be purchased for use by any airline.

Good luck getting to America in anything that's quieter.

Its good you posted this info because i am sure the Baron believes nothing takes of to the south. The 777 is a modern aircraft and meets all the noise regulations as do the 737's and A320's that fly into CNX. There is a big "but" . But if you live in the area at the end of the runway, very close to the airport, under the aircraft as they take off, all these modern "quiet" aircraft are noisy. There is one person on this thread who has a hard time grasping this.

For anyone reading this thread who is confused about the runways. Chiang Mai has one single runway and you can land or take off from either end, two different directions. Landing from the south (heading north) is 36. Take off on 36(three six) you will head north over the city. Landing from the north(heading southwards) is 18(one eight) and rarely used for landings unless there are strong winds. When those little storms occur in March, April or the rainy season runway 18 will be used for 30 mins or so until the wind dies down. Take off on 18 (you are pointing south) you take off to the south.

[BaronOfThunder]

Right. Thank you for the clarification regarding runway referencing and designations. It has been a long time since I flew an airplane, because this is still not permitted for private citizens in many parts of Asia, yet at least I still recall that I always knew the points on the compass designated by the runway numbers. And dead reckoning is easy compared to celestial, which was used during bomber runs over Germany by the high flying Boeing craft of the time. The sextant was stuck out the top of the aircraft, as I recall. With dead reckoning, you take a line of sight to an object. But wind direction is measured from a direction.

It can be confusing.

Wind is from the North

But takeoff is to the North

I mean the degrees of the compass.

[CMsojourner]

Makes sense... as you cross the threshold just before takeoff to the north from CNX, the runway you line up with is "36" -- see https://www.google.co.th/maps/@18.7515659,98.9638533,879m/data=!3m1!1e3?hl=en (click the "Earth" icon in the lower left corner to toggle to Satellite view).

Edited January 5, 2016 by CMsojourner

[Ricardo]

For anyone reading this thread who is confused about the runways. Chiang Mai has one single runway and you can land or take off from either end, two different directions. Landing from the south (heading north) is 36. Take off on 36(three six) you will head north over the city. Landing from the north(heading southwards) is 18(one eight) and rarely used for landings unless there are strong winds. When those little storms occur in March, April or the rainy season runway 18 will be used for 30 mins or so until the wind dies down. Take off on 18 (you are pointing south) you take off to the south.

Thanks, then i got it wrong, not a first !

[elephant45]

www.aisthai.aviation.go.th/webais/pdf/AD%20vol1-CHART/VTCC.pdf

Here are the Standard Instrument Departures for VTCC ( Chiang Mai). Northbound, they are all the same, climb to 2500 ft on RWY heading then on course however way the particular procedure designates or whatever the controller tells you to do. A lighter aircraft will reach that altitude earlier and hence the quicker right turn, but I am certain that Air Asia etc breaks those rules and starts turns early. Temp, wind and humidity change the noise levels and the Thai A-330 seems to be the loudest to me. Its laziness on ATC' part basically not to have more of them depart south as they want to protect their butt with larger spacing intervals between aircraft, say if one is ten miles out on final inbound. But actually probably 30% of them do depart south if they are head to BKK or DMK, etc. The pilot of a Chinese or HKG bound aircraft can request to depart north if he wants but it’s up to the controller which way he authorizes. As far as the OP post, there are many more people and buildings to the north and normal common sense would dictate southern departures wherever possible. They need a new airport pure and simple. And there’s a lot of money to be doled out when that happens to expect it. And the taxi’s will love a 40km drive to the airport, millions of baht there to be had.

[elephant45]

If one of them loses an engine on takeoff and flies into the Maya Mall to go shopping (duty free) things will change. And I don't think the locals care about noise very much.

[harrry]

If one of them loses an engine on takeoff and flies into the Maya Mall to go shopping (duty free) things will change. And I don't think the locals care about noise very much.

Good thing....if that were the case we should shedule all flights between midnight and 6am as Maya is nearly empty then.

Planes losing an engine on takeoff now is not a problem. In fact most of the time a passenger would not even notice till the pilot said he was returning to land.

[elephant45]

If you know what you are doing very well, that is true. May not apply locally. Been there, done it.

[JaseTheBass]

If one of them loses an engine on takeoff and flies into the Maya Mall to go shopping (duty free) things will change. And I don't think the locals care about noise very much.

Good thing....if that were the case we should shedule all flights between midnight and 6am as Maya is nearly empty then.

Planes losing an engine on takeoff now is not a problem. In fact most of the time a passenger would not even notice till the pilot said he was returning to land.

Unless the pilot was French.

[arunsakda]

If one of them loses an engine on takeoff and flies into the Maya Mall to go shopping (duty free) things will change. And I don't think the locals care about noise very much.

Good thing....if that were the case we should shedule all flights between midnight and 6am as Maya is nearly empty then.

Planes losing an engine on takeoff now is not a problem. In fact most of the time a passenger would not even notice till the pilot said he was returning to land.

eh? Rubbish.

[harrry]

If one of them loses an engine on takeoff and flies into the Maya Mall to go shopping (duty free) things will change. And I don't think the locals care about noise very much.

Good thing....if that were the case we should shedule all flights between midnight and 6am as Maya is nearly empty then.

Planes losing an engine on takeoff now is not a problem. In fact most of the time a passenger would not even notice till the pilot said he was returning to land.

eh? Rubbish.

yes your post is

http://esbuzz.net/trends/watch/vid88eZjQjokmsl0

https://youtu.be/eZjQjokmsl0

Edited February 17, 2016 by harrry

[arunsakda]

I am a Captain on the 737 and I have never had an actual engine failure. We do practice them in the simulator regularly and no matter what there is going to be alot of sudden yaw with EFATO. I have been in the back on a 777 that "popped one" during the takeoff roll and the cabin filled with smoke and insulation dust from busted bleed/pack lines. One of the scariest times if my life thinking about choking to death but the smoke cleared quickly and the ANA pilots got us back on the deck in Osaka within 17 minutes . I later found out the engine did not actually fail but they had a compressor stall( loud!) and they did not actually shut down the engine.

I have taken as fact the reality that many people post rubbish on this site as authotitative when they actually have no idea what they are talking about. The idea that passengers would not notice is RUBBISH.

Edited February 17, 2016 by arunsakda

[harrry]

I am a Captain on the 737 and I have never had an actual engine failure. We do practice them in the simulator regularly and no matter what there is going to be alot of sudden yaw with EFATO. I have been in the back on a 777 that "popped one" during the takeoff roll and the cabin filled with smoke and insulation dust from busted bleed/pack lines. One of the scariest times if my life thinking about choking to death but the smoke cleared quickly and the ANA pilots got us back on the deck in Osaka within 17 minutes . I later found out the engine did not actually fail but they had a compressor stall( loud!) and they did not actually shut down the engine.

I have taken as fact the reality that many people post rubbish on this site as authotitative when they actually have no idea what they are talking about. The idea that passengers would not notice is RUBBISH.

You did not comment on my main point that there would not be a real possibility of a plane crashing into Maya because of a single engine failure on takeoff. Almost impossible...though the same could not be said about one crashing into BigC on approach.

[elephant45]

Arunsakda, I agree completely so many posting on here are clueless what it is like to even practice V1 cuts and do them properly, especially fully loaded in hot and humid conditions. I also am/was a professional pilot most of my life. Most of the commenters here fly MS Flight Sim I would guess.