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TK787
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Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:46 am

I just came across this photo in the database today, and wanted to repeat the photographers question for discussion.


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Photo © Philippe Ballerstedt



Could it be just water from the runway , front lit to look darker?
 
jsposaune
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:49 am

Most likely brake dust... There was a thread on here not too long ago with a series of similar pictures.
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kaddyuk
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:59 am

Quoting TK787 (Thread starter):
Could it be just water from the runway , front lit to look darker?

Its simply brake dust from the brake units... it collects in the heat shield between brake unit & wheel on landing and also on the brake torque links.

Its harmless to the aircraft but perhaps not to the environment...
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EMBQA
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:59 am

Brake dust.... Try a search. This is VERY well covered and several great threads with some great information.
"It's not the size of the dog in the fight, but the size of the fight in the dog"
 
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PipoA380
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 9:01 am

Thanks for raising that question TK787, as this is my photo, I'm wondering what it is!

Quoting Jsposaune (Reply 1):
Most likely brake dust

Why would that brake dust come out at takeoff, would it be from the braking during the preceeding landing? Or during taxiing to the runway?

Thanks in advance
Philippe
It's not about AIRBUS. it's not about BOEING. It's all about the beauty of FLYING.
 
kaddyuk
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 9:04 am

Quoting PipoA380 (Reply 4):
Why would that brake dust come out at takeoff, would it be from the braking during the preceeding landing? Or during taxiing to the runway?

But the aircraft will have landed previous to the takeoff. It will come to a stop and move reasonably slowly preventing the dust to blow away.

The brake units wear by about 1 or 2 1/1000ths of an inch each time they're used. This can and does build up, eventually it blows off...
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TK787
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 9:06 am

Quoting PipoA380 (Reply 4):
Thanks for raising that question TK787, as this is my photo, I'm wondering what it is!

Nice photo by the way. And what a nice way to meet a photographer.
I just didn't know if you visit the forums or not, so I posted it. Wouldn't want to step on your toes.
 
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PipoA380
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 9:07 am

Quoting Kaddyuk (Reply 5):
But the aircraft will have landed previous to the takeoff

Okay, that's what I meant with "would it be from the braking during the preceeding landing".

Quoting Kaddyuk (Reply 5):
This can and does build up, eventually it blows off...

Okay, that explains why you don't see it every time. Thanks for these infos kaddyuk

Quoting TK787 (Reply 6):
Nice photo by the way. And what a nice way to meet a photographer.
I just didn't know if you visit the forums or not, so I posted it. Wouldn't want to step on your toes.


Thanks for the comment. It's a complete coincidence by the way, the title seemed interesting, I was surprised to see my image Nice to meet you too!
Regards
Philippe

[Edited 2006-08-09 02:11:42]
It's not about AIRBUS. it's not about BOEING. It's all about the beauty of FLYING.
 
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HAWK21M
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 6:10 pm

Brake Dust.
regds
MEL
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LH526
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 6:16 pm

As covered, it's brake dust!
It's safer to have the wheels retracted after they have come to a complete stiop, hence some seconds before retracting the gear the wheels (wich still run at take off speed rotation) will be slowed down by the brakes to prevent rotatation in the wheel well.

Mario
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lufthansi
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 6:32 pm

Try to take a bicyles wheel and hold in in your hand while it is turning. Now do the movement of the retracting landing gear. The gyro forces would put the whole aircraft in rotation/sideward movement. Gyro forces always react against the force you put in when "retracting" your bicycle wheel. Actio=reactio

This experiment is even more impressive when you sit on a moveable office chair with wheels. It will start to turn during your experiment as a reaction of your input force.

This is how the old standby horizons for i.e. A gyro remains it's axis' direction in a room. So the aircraft is turning around the stby. horizon. No imagine the aircraft to rotate around the landing gear...

Maybe someone finds a good physical site in English...

Stephan
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HAWK21M
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:00 pm

Quoting LH526 (Reply 9):
It's safer to have the wheels retracted after they have come to a complete stiop, hence some seconds before retracting the gear the wheels (wich still run at take off speed rotation) will be slowed down by the brakes to prevent rotatation in the wheel well.

Auto Retract Braking serves the Purpose.
regds
MEL
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LH526
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RE: Picture Of Smoke Coming From Landing Gear.

Wed Aug 09, 2006 8:49 pm

Quoting HAWK21M (Reply 11):
Auto Retract Braking serves the Purpose.

Yep, that's what I described (or tried to) above.
Thanks for the exakt term Mel!

Mario
LH526
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PipoA380
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RE: Picture Of Smoke Coming From Landing Gear.

Thu Aug 10, 2006 4:16 am

I got a mail from someone working at ATC in Amsterdam, here's the mail:

"Probably hot brakes...it is a long way to the runway. He was flying a long time with his gear down , when I asked him if he had any problems....he anwered ..."just hot brakes, keeping the gear down for cooling" That happened somewhere near the date this picture was made."

Excellent coincidence if it really was the same day! Big grin

Regards
Philippe
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scbriml
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RE: Picture Of Smoke Coming From Landing Gear.

Thu Aug 10, 2006 4:40 am

It's a pretty common occurance with just about all types, but more noticable on big ones.
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airfrance
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RE: Picture Of Smoke Coming From Landing Gear.

Thu Aug 10, 2006 4:57 am

It is brake dust. Most maybe all planes have brake dust in the air after they takeoff from the runway.
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kaddyuk
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RE: Picture Of Smoke Coming From Landing Gear.

Thu Aug 10, 2006 5:03 am

Quoting AirFrance (Reply 15):
Most maybe all planes have brake dust in the air after they takeoff from the runway

Most certainly, however you need the right conditions to be able to see it  Smile
Whoever said "laughter is the best medicine" never had Gonorrhea
 
KC135R
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RE: Picture Of Smoke Coming From Landing Gear.

Thu Aug 10, 2006 8:50 am

Quoting PipoA380 (Reply 13):
Probably hot brakes

I seriously doubt that since it appears as if (judging by the nose gear doors) the gear is beginning the retraction sequence. If it is retracting, the braking that occurs automatically during retraction is the cause, as explained above by a couple of people.

On the planes I work, you can see it each and every time you watch one take off - just after the gear unlocks and begins moving the brakes auto-actuate and there's a puff of black smoke as the dust comes off.