Are There Strange Wind Conditions At Chiang Mai Airport?

[vegas]

A group of us went to Chiang Mai on the weekend and upon meeting for a drink later, 4 people, who had arrived on 4 different airlines (Thai, English pilots) all commented on a very heavy landing where the plane bounced all the way down the runway. We came in so fast that I thought we were going to career off the end of the runway. One of the guys asked the stewardess (English) why such a heavy landing?? and she said it was due to the wind. Well, we were in Chiang Mai for 3 days and skys were clear without so much as a wisp of wind.

Any pilots out there that can comment on this phenomenon?

[uptheos]

I came back from Bangkok on Air Asia Tuesday evening. It was certainly the bumpiest landing I've had for quite some time. To me, it seemed as if the plane was approaching the runway faster than usual, but being dark it's hard to say. The plane coming from Chiangmai was over an hour late arriving at Bangkok.

[cmsally]

The new Boeing planes that Nok Air are using come in much faster . And then really brake or reverse throttle or whatever they do before they stop.

We had a really rough landing in BKK but a good one in CM. My guess is with this plane if you don't get it exactly right you tend to bounce down the runway.

Any pilots out there to comment?

[cm-happy]

Maybe its just a matter of the pilots giving their #1's(co-pilots) landing experience

[tigerbeer]

The new Boeing planes that Nok Air are using come in much faster . And then really brake or reverse throttle or whatever they do before they stop.

We had a really rough landing in BKK but a good one in CM. My guess is with this plane if you don't get it exactly right you tend to bounce down the runway.

Any pilots out there to comment?

those are certainly not new Boeing jets.

[CobraSnakeNecktie]

The new Boeing planes that Nok Air are using come in much faster . And then really brake or reverse throttle or whatever they do before they stop.

We had a really rough landing in BKK but a good one in CM. My guess is with this plane if you don't get it exactly right you tend to bounce down the runway.

Any pilots out there to comment?

Not a pilot but have flown in private planes in the past.

there is a airspeed based on aerodynamics where during landing the plane loses lift and can stop flying which would be called stall speed. Conversely there is a air speed where the wing gains lift and can take off. These two speeds are often close but landings tend to be about 20 -30% slower than takeoffs.

Whether or not the landing is bumpy is not a function of speed ( i.e. slower speed equals smoother or rougher landing) but either pilot skill or wind conditions causing issues like crosswinds which require larger corrections in direction from flight to landing.

Aircraft Takeoff Weight Takeoff Speed

Boeing 737 100,000 lb

45,360 kg 150 mph

250 km/h

130 kts

Boeing 757 240,000 lb

108,860 kg 160 mph

260 km/h

140 kts

Airbus A320 155,000 lb

70,305 kg 170 mph

275 km/h

150 kts

Airbus A340 571,000 lb

259,000 kg 180 mph

290 km/h

155 kts

Boeing 747 800,000 lb

362,870 kg 180 mph

290 km/h

155 kts

[cmsally]

The new Boeing planes that Nok Air are using come in much faster . And then really brake or reverse throttle or whatever they do before they stop.

We had a really rough landing in BKK but a good one in CM. My guess is with this plane if you don't get it exactly right you tend to bounce down the runway.

Any pilots out there to comment?

those are certainly not new Boeing jets.

Agreed, definitely not new, just "new" to Nok Air.

[Dustoff]

Ground speed while landing is affected by wind. While aircraft land into the wind, if there is no wind, ground speed will be higher even when the airspeed remains constant.

Unless the wind is quite strong and/or gusty, most turbulence close to the ground is caused by thermals. Materials on the ground are heated by the sun then radiate secondary heat in the form of rising columns of hot air; and different materials radiate different amounts of heat. Water radiates very little but plowed fields, roads and such radiate a lot and can cause a bit of a bumpy ride/landing when passing through these varying thermals on approach.

In helicopters we used to say that a successful landing is one everybody walks away from...

(edited for spellink)

Edited December 19, 2007 by Dustoff

[bunta71]

Success is such a subjective word,especially when hangar-flying. When I came to rest upside down that afternoon in Willow we all walked away except from the $9000 parts bill that made the afternoon seem unsuccessful,but can still tell the story at least. No humor or wordsmithery here my friend ,only the facts ...Jack

[bunta71]

Dustoff had the most relevant answer...There are so many variables when landing at night it boggles the mind. ANY one of which can can produce landings that are as described in the beginning posts. Some of them are, but not limited to:

Perceptions as when to begin your flare,remembering that most pilots in the heavies are sitting 30+ feet off the ground,and we are talking about in the dark with variable glares from lights,etc.

Transitioning OR NOT from holding off your landing to making a split second decision as whether or not to "plant your landing" as soon as you initially touchdown;

Making that initial touch down after giving a little more thrust (throttle) making you a tad bit faster than what would be perfect speedwise can make you bounce several times down the runway;

Being a little lighter than what you are accustomed to for the aircraft you are flying;

Or a myriad of other factors which makes landing a definite art and when you have a chance to thank a pilot that does a particularly good landing sometime," do it!" and appreciate the complexities barely touched upon here. Now can we NOT be serious for a while?

[Ricardo]

The new Boeing planes that Nok Air are using come in much faster . And then really brake or reverse throttle or whatever they do before they stop.

We had a really rough landing in BKK but a good one in CM. My guess is with this plane if you don't get it exactly right you tend to bounce down the runway.

Any pilots out there to comment?

those are certainly not new Boeing jets.

Agreed, definitely not new, just "new" to Nok Air.

I think the original reference may have been to the modern 737-800, currently being used a lot on the DMK-CNX route, which is on short-term wet-lease to Nok-Air from XL of the UK... there are some pictures on a thread in the Travel forum.

[Thaihog]

You know what pilots say " a good landing, is one you walk away from" LOL......