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donnlass
12th Apr 2009, 11:27
Greetings All

I was flying back from Belfast International in 2006 on BMI Baby 737-300 to Manchester in 2006 it was filthy night, raining hard and holwing a gale.

On the descent to land, the flap settings were changed at least 6 times and the aircraft made a fast hard landing.

Would altering the flap/slat settings that many times be normal coming in to land in that kind of weather and haow are they affected by different weather conditions?

Cheers

Donnlass:eek:

Doors to Automatic
12th Apr 2009, 11:38
The 737 has flap settings for 1,2,5,10,15,25,30 and 40 degrees so in theory it is possible to make 8 changes of flap during an approach.

In practice flaps will be set to 1,5,15,30 and 40 during most approaches. Some carriers don't use flaps 40 as the extra drag causes additional engine noise and increased fuel consumption but it does allow for a slower landing speed so it is useful on short runways such as Jersey and Aberdeen.

In very windy conditions like you described pilots will generally not use flap 40 as flap 30 gives a faster more stable approach and a more nimble response to any sudden wind speed changes.

So to answer your question what you saw was not unusual and the firm landing would have been intentional to get the plane on the ground as quickly as possible and to make firm contact with the runway to prevent aquaplaning.

Rainboe
12th Apr 2009, 11:49
I wouldn't go for a smoothie in conditions like that! Sounds to me they did a classic good landing in atrocious weather, if maybe harder than you think appropriate, but then you weren't flying it! Do you think in those conditions your problems are over once you are actually on the ground? Getting effective braking, stopping the upwind wing lifting and trying to steer down a wet aquaplaning runway is still a real handful! They did well.

donnlass
12th Apr 2009, 13:27
Thanks for your replies, was just wondering what the normal settings were for those conditions.

True I wasnt flying it (leave that to the experts - toxic or not :) :ok:) but am more aware of the problems of flying in those conditions and my respect for those who pilot us safely wherever we want to go remains high.

Cheers

Donnlass

Load Toad
12th Apr 2009, 16:19
Rainboe,
You are obviously clever, informed, knowledgeable etc.

Any chance you could just turn the outrage button down a touch? It's like bukkake on a 42" TV mate - more than we need.

L337
13th Apr 2009, 08:53
Any chance you could just turn the outrage button down a touch

But that's his charm? PPRuNe needs him. Sometimes you need the truth right between the eyes.

I am sure in real life he is just a cuddly fluffy bunny.

/hugz

smudgethecat
13th Apr 2009, 09:12
Here, here, you couldnt wish for a better person than him for dealing with some of the fruit cakes who lurk on this forum.:ok:

Load Toad
15th Apr 2009, 08:08
I prefer to think of him as a big cuddly old teddy bear getting occasionally grouchy & in need of a big hug.

But tempering the social venom and vitriol would mean it had a greater impact when it was really needed. Like bukkake.