The Boeing Triple 7

"George Patterson" wrote in message
news:kbmle.263$zb.134@trndny04...
Both heating and air conditioning systems are dehumidifiers.

How so?

When cooling air below ambient, an air conditioner does dehumidify. But the
net temperature change in an airliner is positive, and it's heated before
it's cooled. No loss of moisture there. Heating air does lower the
*relative* humidity, but that doesn't mean that moisture has actually been
removed (which is what dehumidifying is). No loss of moisture there either.

At what point is it that you believe moisture is actually *removed* from the
cabin air in an airliner?

Pete

"Matt Barrow" wrote in message
...

"William W. Plummer" wrote in message
...
Allen wrote:
"Paul kgyy" wrote in message
oups.com...

I think it was in the days when American was removing olives from the
salads to save money.



And cutting their flight attendant's pay while giving their executives
free
Mercedes cars.

The attendants are free to find other employment.

A good executive can save a dying company (Nelson at UPS, Louis-Dreyfus at
Adidas, Bethune at Continental, Bonsignore at Honeywell, Welch at GE...),
attendants can only **** up a company -- doing their job is "normal".

What good executive, knowing that disgruntled employees can only "**** up" a
company, would not at least put on the show of appeasement?

I recently attended a seminar given by one of the 777 engineers about the
777 design process. Couple things I found particularly interesting:
apparently one of the primary reasons that the 777 was developed as a "new"
aircraft (instead of just a new version of the 767 as originally planned)
was because of all the problems with the 747-400 when it came out. The
airlines were getting sick of having to sort through all the bugs on new
aircraft, so one of Boeings primary objectives with the 777 was to have a
plane that was ready to fly right from the start.

The other interesting thing was that the 777 was originally designed with
folding wing (like some navy jets) in order to be able to fit into smaller
gates. None of the airliners wanted anything to do with the folding wing,
but apparently, until recently, the folding wing was still listed as an
option in the 777 catalog.

- Ray



"Jay Honeck" wrote in message
news:Cg5le.7245$PS3.6886@attbi_s22...
...is simply an awesome aircraft.

With 9 rows across (2+5+2) in an aircraft as long as a 747 -- but with
only
two gigantic engines -- modern materials, an excellent sound system, and
little video screens in the seat backs, I was absolutely astounded at the
comfort and ride of this plane.

I've flown first and second-generation jet airliners (707s, DC-9s, 727s,
DC-10s, L-1011s, MD-80s) and was always annoyed at one thing or another,
usually the whiny noise level and air handling systems. Boeing has
addressed both issues in the 777, and in the three different aircraft we
rode in the noise level was almost unnaturally low -- and the air was
fresh
without being overly dry.

And having a moving-map GPS display right in front of me was very cool,
too!
(612 mph was our top ground speed -- at 35,000 feet.)

The new 787 Dreamliner is supposed to incorporate all the breakthroughs
from
the 777, plus take advantage of the lightness and strength of composite
materials. Having just toured the immense plant where it is to be built,
let's hope Boeing has another winner in the wings...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Ray" wrote in message
...
I recently attended a seminar given by one of the 777 engineers about the
777 design process. Couple things I found particularly interesting:
apparently one of the primary reasons that the 777 was developed as a
"new"
aircraft (instead of just a new version of the 767 as originally planned)
was because of all the problems with the 747-400 when it came out. The
airlines were getting sick of having to sort through all the bugs on new
aircraft, so one of Boeings primary objectives with the 777 was to have a
plane that was ready to fly right from the start.

The other interesting thing was that the 777 was originally designed with
folding wing (like some navy jets) in order to be able to fit into smaller
gates. None of the airliners wanted anything to do with the folding wing,
but apparently, until recently, the folding wing was still listed as an
option in the 777 catalog.

- Ray


Hi Ray,

Yes, the folding wing is still a design option that was never adopted. It
was thought that some airports would require it to allow the 777 to berth at
gates that couldn't handle its wing span. That turned out to be a non-issue
in most cases.

The 747-400 was a problem child for Boeing. It was sold as a "light touch"
upgrade to the 747 but was very much a new version all the way around. Too
much work with too little committed resources led to some real problems. In
engineering circles, every time we hear our management talk about a product
generation update as being "light touch" we cringe...

Dean

George Patterson wrote:

Peter Duniho wrote:


The only way I can see for a jet to have "a reputation for being very
dry" is for the jet to be equipped with a DEhumidifier. Which, of
course, they aren't.


Both heating and air conditioning systems are dehumidifiers.

Yes, but one affects only RH, while the other actually removes water
from the air.


Matt

Ray wrote:

the 777, plus take advantage of the lightness and strength of composite
materials. Having just toured the immense plant where it is to be built,
let's hope Boeing has another winner in the wings...

Kind of like the tails on some Airbus models? :-)


Matt

"Jay Honeck" wrote in message
news:8_9le.6357$IC6.755@attbi_s72...
The 777 is not that good. Having crossed the Atlantic many times in it,
it is my least liked aircraft. It has a reputation for being very dry.
Try it on an 11 hour flight. Last month I got through three litres of
water during a flight from Beijing to London

Hmm. I wonder if it's where you're seated, cuz we didn't find this to be
the case at all. Usually I'm totally desiccated after an airline flight,
but not on this bird.


Done it in coach and business still the same. Flight attendants complain
about it all the time and I suppose they are probably a better judge than
anyone.

Seen all those wizened old wreck flight attendants that look as though they
are 90 years old. Unique to the 777. In truth they are only 25. FAs look
much younger on other aircraft.

I heard a story from the BA crew I travelled back from Beijing with that in
their stopover hotel was a US airline crew with a 80 year old flight
attendant in the crew.

wrote in message
oups.com...
Hi Jay,

I forgot to include a link to some photos from my days working on the
777. They are on my website at http://www.razorsedgesoft.com/777.htm

WHAT A BEAUTIFUL OFFICE ! ! !

It seems so uncluttered. The overhead seems to be so less cluttered, than
most overheads I have seen. Is there any LCD stuff up there, or just
transparent overlays, making all of the lines? Are the lines linking
systems, and functions?

Great photography. I suppose that was a professional sales photo? I wonder
how many planes had to go around, while the plane sat at the end of the
runway for the photo shoot. g
--
Jim in NC

On Thu, 26 May 2005 10:28:43 -0700, "Peter Duniho"
wrote:

"George Patterson" wrote in message
news:tdmle.264$zb.121@trndny04...
Perhaps some aircraft are equipped with humidifiers for the inside air?

A humidifier would require the carriage of water; beyond that already
required for the galley and lavatories, of course.

I'm not aware of any jet with a humidifier. Certainly, my friend at Boeing
claims that no commonly used commercial airliner has a humidifier.

The 744 had humidifiers as a carrier option. Most didn't opt for it,
or disabled them when they turned out to be more aggravation than they
were worth.

"Peter Duniho" wrote

At what point is it that you believe moisture is actually *removed*
from the cabin air in an airliner?

Qouting from my B-707 and B-727 Flight Manuals:

WATER SEPARATOR
A water separator is installed in the Air Cycle Machine turbine
output duct to remove water by centrifugal action from the cold
air.
ANTI-ICING CONTROL VALVE
An anti-icing control valve is installed to automatically route
warm air from the Primary Heat Exchanger into the water separator
to prevent icing when airflow temperature drops below 40 degrees.


When the water separator valve does ice-up, it starts snowing
from the air conditioning vents in the cabin.

Bob Moore
17 years in the Boeing 707
PanAm (retired)