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Maxx.
February 5th 06, 04:01 PM
Gentlemen, (& ladies):

As a frequent flyer, I've had my share of rough weather flying &
landings. My most vivid memory is a flight from ORD to IAH a few years
back in Tropical Storm Alison. As we started to touch down, we
suddenly went back up, and were diverted because the control tower
flooded, and blacked out. I remember watching out the window at the
massive amounts of rain hitting the plane. What I'm wondering is:

How much water can these engines suck in before they start to foul out?

Geoff Glave
February 5th 06, 05:44 PM
> How much water can these engines suck in before they start to foul out?

I remember watching a documentary on PBS several years ago about the
development of the triple seven. They showed Pratt & Whitney developing the
new engines. The engines were running on the test bed and they basically
had something like four huge firehoses spraying water in the engines. They
didn't miss a beat.

Cheers,
Geoff Glave
Vancouver, Canada

Rachel
February 5th 06, 06:24 PM
Maxx. wrote:
> Gentlemen, (& ladies):
>
> As a frequent flyer, I've had my share of rough weather flying &
> landings. My most vivid memory is a flight from ORD to IAH a few years
> back in Tropical Storm Alison. As we started to touch down, we
> suddenly went back up, and were diverted because the control tower
> flooded, and blacked out. I remember watching out the window at the
> massive amounts of rain hitting the plane. What I'm wondering is:
>
> How much water can these engines suck in before they start to foul out?
>
They do test them to withstand quite a bit of water. The other thing
is, airplanes like that use continuous ignition during rainstorms.

John Gaquin
February 5th 06, 07:00 PM
"Maxx." > wrote in message .
>
> How much water can these engines suck in before they start to foul out?

An awful lot. Years ago there was an accident involving a Southern Airways
DC9 that inadvertently flew into a very large cell and flamed out both
engines with water and hail ingestion [in truth, I can't recall if that was
determined or theorized.]. "Landed" dead-stick on a road, I think Many
killed. That's the only one I can recall off the top of my head. Probably
other examples, but the engines can take an astounding quantity of water.
I've encountered rain heavy enough at approach speed that the wipers on high
speed couldn't even hope to keep up, but the Pratts, God bless 'em, never
even burped.

Robert J Carpenter
February 5th 06, 08:06 PM
"John Gaquin" > wrote in message
...
>
> "Maxx." > wrote in message .
>>
>> How much water can these engines suck in before they start to foul
>> out?
>
> An awful lot. Years ago there was an accident involving a Southern
> Airways DC9 that inadvertently flew into a very large cell and
> flamed out both engines with water and hail ingestion [in truth, I
> can't recall if that was determined or theorized.]. "Landed"
> dead-stick on a road, I think

I think that you'll find the problem is hail / ice. That tends to
clean out the blades in a jet engine killng it. There have been
(business??) jets that suffered engine failure when they allowed ice
to build up on the engine cowling and THEN turned on the deicing
heater. The ice came loose and went through the engine - killing it.
They would not have had a problem had they turned on the heat before
the ice buildup.

Dave S
February 5th 06, 08:22 PM
Maxx. wrote:
> Gentlemen, (& ladies):
>
As we started to touch down, we
> suddenly went back up, and were diverted because the control tower
> flooded, and blacked out.

Not to detract from your question, the Control Tower didn't flood during
Allison/2001. The Houston TRACON (Approach Control) is what flooded and
went off-line. Houston Approach is located in the basement of the OLD
control tower at IAH, west of Terminal A. It's truly a dungeon down there.

Their function was taken over by Houston Center, down the road, in a
sprawling above-ground facility, until the problem could be fixed
(again). One day, there is supposed to be a mega-approach placed in
operation near Conroe, that will allegedly combine Houston, Beaumont,
San Antonio and Austin all in one facility.

The new IAH control tower never flooded.

I question that you were touching down, because if you had wheels on the
ground, you were likely going around due to another object still on the
runway. If you were on approach, and had not touched down yet, then the
go-around due to a facility going offline is understandable.

Dave

Maxx.
February 5th 06, 09:12 PM
Dave S wrote:
> Maxx. wrote:
> > Gentlemen, (& ladies):
> >
> As we started to touch down, we
> > suddenly went back up, and were diverted because the control tower
> > flooded, and blacked out.
>
> Not to detract from your question, the Control Tower didn't flood during
> Allison/2001. The Houston TRACON (Approach Control) is what flooded and
> went off-line. Houston Approach is located in the basement of the OLD
> control tower at IAH, west of Terminal A. It's truly a dungeon down there.
>
> Their function was taken over by Houston Center, down the road, in a
> sprawling above-ground facility, until the problem could be fixed
> (again). One day, there is supposed to be a mega-approach placed in
> operation near Conroe, that will allegedly combine Houston, Beaumont,
> San Antonio and Austin all in one facility.
>
> The new IAH control tower never flooded.
>
> I question that you were touching down, because if you had wheels on the
> ground, you were likely going around due to another object still on the
> runway. If you were on approach, and had not touched down yet, then the
> go-around due to a facility going offline is understandable.
>
> Dave

I was sitting in a window seat at the time, just ahead of the right
engine. I saw the white lines of the runway before we went back up.
(it was actually that close to touching down.) Wheels never touched
the ground though. The flooding issue was announced by the pilot after
we had climbed enough (for his comfort, I guess) We then went to Lake
Charles, sat for awhile getting fuel, then flew to Austin, where we
were bussed back to IAH. That night, ORD to IAH = 20 hours & my
luggage was delivered four days later..

So what actually flooded? I don't know. I was busy watching the water
going into the engine, and thinking about my Chevy Cavalier running
through a puddle. <cough, choke, oops>

Kyle Boatright
February 5th 06, 10:50 PM
"John Gaquin" > wrote in message
...
>
> "Maxx." > wrote in message .
>>
>> How much water can these engines suck in before they start to foul out?
>
> An awful lot. Years ago there was an accident involving a Southern
> Airways DC9 that inadvertently flew into a very large cell and flamed out
> both engines with water and hail ingestion [in truth, I can't recall if
> that was determined or theorized.]. "Landed" dead-stick on a road, I
> think Many killed. That's the only one I can recall off the top of my
> head. Probably other examples, but the engines can take an astounding
> quantity of water. I've encountered rain heavy enough at approach speed
> that the wipers on high speed couldn't even hope to keep up, but the
> Pratts, God bless 'em, never even burped.
>

The smoke from that crash was visible from my childhood home, and we had
emergency vehicles running from New Hope, GA (where the crash occurred) and
by our house for hours that afternoon/evening.

Apparently, the aircraft entered a very nasty t-storm, which flooded out the
engines. According to a family friend who participated in the investigation,
the engines were over-heated and ruined when re-starts were attempted with
too much fuel fed to the engines.

One of the sadder aspects of the crash is that there were several aircraft
within gliding range of that DC-9, with the most obvious being my home
field - VPC. The DC-9 more or less overflew the field during its descent,
only to crash attempting a landing on a public road.

KB

Marty
February 7th 06, 05:05 AM
> wrote in message
ups.com...
>
> For some aircraft, mostly the largest ones, some go arounds can
> still result in the gear touching down. They are pretty late in the
> game, but there are points at which they cannot stop the descent
> soon enough and they will touch down.
>

At OSH, before they extended R18-36, I watched a T & G by a (NWA?) 747. The
engines were spooling up well before the mains touched down and I don't
believe there was any PAX onboard. Was that a short field proccedure? Or
just for the show? They may have well been able to keep it from settling
down because when they did rotate, it pitched up and climbed like a.....you
know.

Marty

John Gaquin
February 9th 06, 04:05 AM
"Marty" > wrote in message news:3d21>>
>
> At OSH, before they extended R18-36, I watched a T & G by a (NWA?) 747.
> The engines were spooling up well before the mains touched down and I
> don't believe there was any PAX onboard. Was that a short field
> proccedure? Or just for the show? They may have well been able to keep it
> from settling down because when they did rotate, it pitched up and climbed
> like a.....you know.

An empty 747 *will* climb like one of those......

On a go around in a 747 or other long aircraft, one element of concern is
pitch angle. In the 747, if you exceed 12 degrees (iirc) you'll tail strike
rather than touch on the mains. So you set a limited rotation angle until
the power and acceleration give you a pos rate of climb. If a touch occurs
before that, it will be on the wheels. Then increase pitch accordingly in
the climbout.

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