How Boeing steered tanker bid

"Tarver Engineering" wrote:


"Gord Beaman" wrote in message
.. .
(sid) wrote:


I should have framed the question this way:
How far would either aircraft fly if there is trouble in the E&E bay
that compromises the electrical system and you are down to DC
power...And then you lose even that?

Isn't that like saying "what would happen if the bloody wings
were to fall off"?...pretty silly statement imo.

I can't understand the obsession with DC power either. Airplanes mostly use
AC power for controls. I have yet to see a synchro that runs on DC.

Almost all a/c generate A.C. power then transform and rectify
some of it to DC with TRU's so the only emergency supply of DC is
a very short lived set of batteries mostly used for emergency
flight instruments and other very essential services. In 26 years
of flying (13,000 hours) I've never lost all A.C. power on any
a/c (nor heard of any of my friends doing it either) so it's not
one of those 'ho hum' occurrences.
--

-Gord.

"Gord Beaman" wrote in message
...
"Tarver Engineering" wrote:


"Gord Beaman" wrote in message
.. .
(sid) wrote:


I should have framed the question this way:
How far would either aircraft fly if there is trouble in the E&E bay
that compromises the electrical system and you are down to DC
power...And then you lose even that?

Isn't that like saying "what would happen if the bloody wings
were to fall off"?...pretty silly statement imo.

I can't understand the obsession with DC power either. Airplanes mostly
use
AC power for controls. I have yet to see a synchro that runs on DC.

Almost all a/c generate A.C. power then transform and rectify
some of it to DC with TRU's so the only emergency supply of DC is
a very short lived set of batteries mostly used for emergency
flight instruments and other very essential services.

I believe the 767 has 2 DC generators on the engines.

In 26 years
of flying (13,000 hours) I've never lost all A.C. power on any
a/c (nor heard of any of my friends doing it either) so it's not
one of those 'ho hum' occurrences.

No gyros could get ugly fast.

I have to wonder at the posters assertion that there is a fault problem with
the 767 E&E bay. It is well known in industry that it rains in the
A-330/340 E&E bay and I doubt USAF would see that as a selling point.

"Tarver Engineering" wrote in message ...
"Gord Beaman" wrote in message
...
(sid) wrote:


I should have framed the question this way:
How far would either aircraft fly if there is trouble in the E&E bay
that compromises the electrical system and you are down to DC
power...And then you lose even that?

Isn't that like saying "what would happen if the bloody wings
were to fall off"?...pretty silly statement imo.

I can't understand the obsession with DC power either. Airplanes mostly use
AC power for controls. I have yet to see a synchro that runs on DC.

Further assurance of maintaining proper attitude can come from
dedicated power sources. In the last five minutes of the 1998 tragedy
of Swissair Flight 111, with a raging electrically stoked fire
spreading from the attic space in the cockpit, the two pilots had no
attitude reference at all—not even a turn needle or turn coordinator
to fall back on. They saw inky blackness on the outside and black
primary flight displays [PDFs] inside the cockpit. The standby ADI,
even if it had been working, was located near the bottom center of the
instrument panel. It was poorly lit and even more difficult to see
while wearing smoke masks.

The Swissair jet's standby was lost because it had been hooked to a
vulnerable hot battery bus. When it failed, the powerless gyro started
to spin down. Therein lies a vital object lesson in redundancy:
Standby instruments need their own batteries, so that a loss of
generated power doesn't take down the sole fallback attitude
reference.

"sid" wrote in message
om...
"Tarver Engineering" wrote in message
...
"Gord Beaman" wrote in message
...
(sid) wrote:


I should have framed the question this way:
How far would either aircraft fly if there is trouble in the E&E bay
that compromises the electrical system and you are down to DC
power...And then you lose even that?

Isn't that like saying "what would happen if the bloody wings
were to fall off"?...pretty silly statement imo.

I can't understand the obsession with DC power either. Airplanes mostly
use
AC power for controls. I have yet to see a synchro that runs on DC.

Further assurance of maintaining proper attitude can come from
dedicated power sources. In the last five minutes of the 1998 tragedy
of Swissair Flight 111, with a raging electrically stoked fire
spreading from the attic space in the cockpit, the two pilots had no
attitude reference at all-not even a turn needle or turn coordinator
to fall back on. They saw inky blackness on the outside and black
primary flight displays [PDFs] inside the cockpit. The standby ADI,
even if it had been working, was located near the bottom center of the
instrument panel. It was poorly lit and even more difficult to see
while wearing smoke masks.

Yep, old Marky Ostendorf modified the airplane such that there was a half
assed exension cord in the cieling carrying 55 Ampres of AC derived from the
battery bus.

The Swissair jet's standby was lost because it had been hooked to a
vulnerable hot battery bus. When it failed, the powerless gyro started
to spin down. Therein lies a vital object lesson in redundancy:
Standby instruments need their own batteries, so that a loss of
generated power doesn't take down the sole fallback attitude
reference.

None of that mattered when the magnetic contacter triped bac in and th arc
tracing wire bundle burned an 18 feet long hole in the fuse; including
cutting the doubler at dorr #1. Writing about a case of manslaughter by way
of gross negligence is no reflection whatsover WRT Boeing, or AI airplanes.

"Gord Beaman" ) wrote in message . ..
(sid) wrote:


I should have framed the question this way:
How far would either aircraft fly if there is trouble in the E&E bay
that compromises the electrical system and you are down to DC
power...And then you lose even that?

Isn't that like saying "what would happen if the bloody wings
were to fall off"?...pretty silly statement imo.
Basically trouble in the E&E bay is nearly as bad as losing both wings...
http://www.findarticles.com/cf_dls/m.../article.jhtml