Leaving all engines running at the gate

Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo. After all the passengers got off the
entire crew, both cabin AND cockpit crew got off and went to the
transit lounge for about an hour before returning to board for the SDQ
leg. All this time the engines were left running. In fact, they
never stopped running the whole time they were at SJU. I have never
seen an airliner do this before and was wondering if something was
wrong with this particular aircraft or if this is some kind of new
"windmilling" feature on the new A346 or something. Perhaps related,
I've heard that IB have had a horrible experience with their new A346s
and this particular aircraft, EC-INO (Gaudi), the first one they
received, is said to have given then more headaches than all the
others.

What circumcstances would make an airline leave a plane guzzling gas
for such a long time on the ground?

John wrote:

Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo.

If you could see the engines turning, it means that they were shut off and
just slowly turning due to wind.

It would be very hard for maintenance personel to get near the aircraft with
all 4 engines running. And I suspect extremely hazardous (if not illegal) to
refuel while engines are running.

It is far more likely that what you saw were just engines turning slowly due
to wind.

There are situations where engines on one side are left running in extreme
cold arctic conditions, and all passenger, cargo, fuel is handled from the
other side. This is to ensure that at least one engine is available to
generate sufficient power to restart the second engine.

"snowy squirrel" wrote in message
...
John wrote:
It is far more likely that what you saw were just engines turning slowly
due
to wind.
Reminds me of what Steven Wright once said. "I used to own a helicopter,
but had no place to park it, so I tied a rope to it, & left it running."

snowy squirrel wrote:

John wrote:

Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo.

If you could see the engines turning, it means that they were shut off and
just slowly turning due to wind.

It would be very hard for maintenance personel to get near the aircraft with
all 4 engines running. And I suspect extremely hazardous (if not illegal) to
refuel while engines are running.

It is far more likely that what you saw were just engines turning slowly due
to wind.

There are situations where engines on one side are left running in extreme
cold arctic conditions, and all passenger, cargo, fuel is handled from the
other side. This is to ensure that at least one engine is available to
generate sufficient power to restart the second engine.

Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

The fans you saw were probably being turned by the wind. The noise you
heard was probably the APU running in the back. Its not unusual for a
plane to sit at the gate with the APU running in the tail of the
plane. Its a jet too and sounds like one.

John wrote in message . ..
Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo. After all the passengers got off the
entire crew, both cabin AND cockpit crew got off and went to the
transit lounge for about an hour before returning to board for the SDQ
leg. All this time the engines were left running. In fact, they
never stopped running the whole time they were at SJU. I have never
seen an airliner do this before and was wondering if something was
wrong with this particular aircraft or if this is some kind of new
"windmilling" feature on the new A346 or something. Perhaps related,
I've heard that IB have had a horrible experience with their new A346s
and this particular aircraft, EC-INO (Gaudi), the first one they
received, is said to have given then more headaches than all the
others.

What circumcstances would make an airline leave a plane guzzling gas
for such a long time on the ground?

"John" wrote in message


Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

Have you ever turned a turbine engine?

--
John T
http://tknowlogy.com/TknoFlyer
http://www.pocketgear.com/products_s...veloperid=4415
____________________

On Tue, 03 Feb 2004 20:28:00 -0500, John wrote:

snowy squirrel wrote:

John wrote:

Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo.

If you could see the engines turning, it means that they were shut off and
just slowly turning due to wind.

It would be very hard for maintenance personel to get near the aircraft with
all 4 engines running. And I suspect extremely hazardous (if not illegal) to
refuel while engines are running.

It is far more likely that what you saw were just engines turning slowly due
to wind.

There are situations where engines on one side are left running in extreme
cold arctic conditions, and all passenger, cargo, fuel is handled from the
other side. This is to ensure that at least one engine is available to
generate sufficient power to restart the second engine.

Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

The fans of a GE90 as fitted to some 777s are much bigger than a 340.
It takes only a light sustained breeze to get them turning and they
can certainly get up to quite a speed. There's not a chance 4 engines
can be left running, let alone have the aircraft loaded, refuelled and
serviced. You will also notice that the first engine isn't started
until the aircraft has started to be pushed back.

MJ

"John" wrote in message

Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

Rotor sections are *extremely* finely balanced, else they would vibrate the
engine right off the wing at operational speeds. What this means is that
the blade wheels will turn freely with very little force applied. A light
breeze will suffice, no hurricane required. In my experience, more often
than not you'll see these things turning (at least with large fan engines)
if there's any breeze exposure at all.


Regards,

John Gaquin
B727, B747

wrote:

On Tue, 03 Feb 2004 20:28:00 -0500, John wrote:

snowy squirrel wrote:

John wrote:

Recently at SJU I saw an IB A340-600 arrive from Madrid that left all
four engines running during the 2 hours that it was at the gate before
continuing to Santo Domingo.

If you could see the engines turning, it means that they were shut off and
just slowly turning due to wind.

It would be very hard for maintenance personel to get near the aircraft with
all 4 engines running. And I suspect extremely hazardous (if not illegal) to
refuel while engines are running.

It is far more likely that what you saw were just engines turning slowly due
to wind.

There are situations where engines on one side are left running in extreme
cold arctic conditions, and all passenger, cargo, fuel is handled from the
other side. This is to ensure that at least one engine is available to
generate sufficient power to restart the second engine.

Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

The fans of a GE90 as fitted to some 777s are much bigger than a 340.
It takes only a light sustained breeze to get them turning and they
can certainly get up to quite a speed. There's not a chance 4 engines
can be left running, let alone have the aircraft loaded, refuelled and
serviced. You will also notice that the first engine isn't started
until the aircraft has started to be pushed back.

MJ

Fine, I'm willing to concede wind turns turbines, never have doubted
it's possible. In fact, I've seen it several times myself. Turbines
turning lazily in the wind, though not at a fairly constant and pretty
fast clip (wind comes and goes, is not constant, certainly not in this
case). But in this case, 1) none of the other 10 or so other jets
adjacent had all their turbines running while parked at their gates,
and 2) this particular jet in question was with its tail to the wind.
Or rather, at about a 45 degree angle, so the wind would have been
blowing against the side of the engines from the back, not straight
in.

But if it was the wind, well hey, my respects to the Wind God. He
showed his mighty powers that day

John wrote:



Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

It takes very little wind to turn the blades.