Curious incident :)

Paul Tomblin wrote:

Since when does smoke come of the tires of a plane starting its takeoff
roll? I can't think of any way that could happen.


Don't know about you but I've seen puffs come off aircraft tires, at
the start of the takeoff roll, often enough; it probably happens when
pilots advance the throttle a bit before releasing the brakes.

Ramapriya

"Ramapriya" wrote in message
oups.com...
Paul Tomblin wrote:

Since when does smoke come of the tires of a plane starting its takeoff
roll? I can't think of any way that could happen.

My thoughts exactly.

Don't know about you but I've seen puffs come off aircraft tires, at
the start of the takeoff roll, often enough; it probably happens when
pilots advance the throttle a bit before releasing the brakes.

I've never seen that, nor even heard of it. The proposed explanation you
suggest certainly wouldn't do it. Smoke comes off the tires during
touchdown because of the speed difference between the tire and the pavement,
until the tire "catches up".

During takeoff, even if the brakes are held, and even if the tires slide a
bit (which is very unlikely...usually the locked wheels can hold the
airplane still), they wouldn't smoke. They'd just rub a bunch of rubber
onto the pavement.

If you saw smoke during the takeoff roll, it came from somewhere other than
the tires.

Pete

Pete

The F-101B had enough engine power that if you held the brakes and ran
up and plugged the burners in it rotated the tires on the rim(s) and
blew them.You could see smoke as they skidded down the R/W.


Technique was to run up to around 80% and check gauges and release
brakes and advance throttle(s) to 100% and plug the burners in.

TOR was less than 1000 feet on a standard day.

Big John
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On Tue, 20 Dec 2005 11:03:22 -0800, "Peter Duniho"
wrote:

"Ramapriya" wrote in message
roups.com...
Paul Tomblin wrote:

Since when does smoke come of the tires of a plane starting its takeoff
roll? I can't think of any way that could happen.

My thoughts exactly.

Don't know about you but I've seen puffs come off aircraft tires, at
the start of the takeoff roll, often enough; it probably happens when
pilots advance the throttle a bit before releasing the brakes.

I've never seen that, nor even heard of it. The proposed explanation you
suggest certainly wouldn't do it. Smoke comes off the tires during
touchdown because of the speed difference between the tire and the pavement,
until the tire "catches up".

During takeoff, even if the brakes are held, and even if the tires slide a
bit (which is very unlikely...usually the locked wheels can hold the
airplane still), they wouldn't smoke. They'd just rub a bunch of rubber
onto the pavement.

If you saw smoke during the takeoff roll, it came from somewhere other than
the tires.

Pete

"Big John" wrote in message
...
The F-101B had enough engine power that if you held the brakes and ran
up and plugged the burners in it rotated the tires on the rim(s) and
blew them.You could see smoke as they skidded down the R/W.

Hardly relevant to the question of what happens at the *very start* of a
takeoff roll of a transport category airplane. Even in the case of the much
higher power-to-weight ratio of the F-101B (or other fighters, for that
matter), the smoke doesn't occur immediately upon power-up.

Pete

Pete

Paul Tomblin posted:

quote

Since when does smoke come off the tires of a plane starting its
takeoff roll? I can't think of any way that could happen.

unquote

My post was only to show that it could and did happen based on my
experience.

Big John
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On Tue, 20 Dec 2005 20:53:41 -0800, "Peter Duniho"
wrote:

"Big John" wrote in message
.. .
The F-101B had enough engine power that if you held the brakes and ran
up and plugged the burners in it rotated the tires on the rim(s) and
blew them.You could see smoke as they skidded down the R/W.

Hardly relevant to the question of what happens at the *very start* of a
takeoff roll of a transport category airplane. Even in the case of the much
higher power-to-weight ratio of the F-101B (or other fighters, for that
matter), the smoke doesn't occur immediately upon power-up.

Pete

"Big John" wrote in message
...
Paul Tomblin posted:

Since when does smoke come off the tires of a plane starting its
takeoff roll? I can't think of any way that could happen.

My post was only to show that it could and did happen based on my
experience.

I appreciate your input. Still, the key phrase in Paul's post is "starting
its takeoff roll". Even in your example, there's no suggestion that the
smoke occurs at the START of the takeoff roll, as described by the person
who started this thread.

Pete

Peter Duniho wrote:

Don't know about you but I've seen puffs come off aircraft tires, at
the start of the takeoff roll, often enough; it probably happens when
pilots advance the throttle a bit before releasing the brakes.

I've never seen that, nor even heard of it. The proposed explanation you
suggest certainly wouldn't do it. Smoke comes off the tires during
touchdown because of the speed difference between the tire and the pavement,
until the tire "catches up".

During takeoff, even if the brakes are held, and even if the tires slide a
bit (which is very unlikely...usually the locked wheels can hold the
airplane still), they wouldn't smoke. They'd just rub a bunch of rubber
onto the pavement.

If you saw smoke during the takeoff roll, it came from somewhere other than
the tires.

Pete

Could be a terminology error here, Pete

As I stated before, I've often seen puffs from behind tires. In fact,
when seeing aircraft readying for a takeoff from behind a glass pane
between the 5 o'clock and 7 o'clock positions, I look for tire puffs to
know that the craft has begun its roll. It could well be a spray of
water or sand off the tarmac, but I have seen it often, no doubt about
it.

Ramapriya

"Ramapriya" wrote in message
ups.com...
Could be a terminology error here, Pete

Well, if you are using the word "smoke" to describe something that is not
actually smoke, I can see how that would be a problem.

Ramapriya wrote:

...when seeing aircraft readying for a takeoff from behind a glass pane
between the 5 o'clock and 7 o'clock positions, I look for tire puffs to
know that the craft has begun its roll. It could well be a spray of
water or sand off the tarmac, but I have seen it often, no doubt about
it.

I don't doubt you've seen something. From five- or seven o'clock it
could be dust kicked up by wing-mounted jet intakes that might appear to
come from the main gear. I've watched a lot of large and heavy jet
departures from the number one position and I don't remember seeing
anything that could be interpreted as smoke from the tires under those
circumstances.

Curious, indeed.


Jack

Jack wrote:

I don't doubt you've seen something. From five- or seven o'clock it
could be dust kicked up by wing-mounted jet intakes that might appear to
come from the main gear. I've watched a lot of large and heavy jet
departures from the number one position and I don't remember seeing
anything that could be interpreted as smoke from the tires under those
circumstances.

Curious, indeed.

Jack


What began as a question to ascertain the frequency of aircraft landing
from above another has turned (due to my poor verbiage, possibly) to
how smoke emerged from the 747's wheels on takeoff

Is it common to see planes commencing their takeoff roll before a
just-landed aircraft has fully turned off into the exit? That clearly
happened in the incident I wrote about too...

Ramapriya