Catastrophic Decompression; Small Place Solo

If a window blows out, everything that is not tied down will certainly be
sucked out, and this could include people if they were small enough.

Its my understanding that in an explosive decompression like this, the
decompression will happen very fast. The Goldfinger episode goes on for 45
minutes of hanging on for dear life while the plane depressurizes. My
un-educated guess is that this would happen in seconds or less.

"Jeff Franks" wrote in message
...

If a window blows out, everything that is not tied down will certainly
be
sucked out, and this could include people if they were small enough.

Its my understanding that in an explosive decompression like this, the
decompression will happen very fast. The Goldfinger episode goes on for
45
minutes of hanging on for dear life while the plane depressurizes. My
un-educated guess is that this would happen in seconds or less.

Witnessed the result of "Port Hole Window" on the starboard side of a C-5
blowing out during "Initial Factory Pressure checks" on a new C-5". The
window itself went through the side of a "Tin Sided Building" ~ 200' from
where the window/port hole came from. A substantial number of the
insulation/batting blankets were torn from their normal place in the cargo
bay & piled on the cargo bay floor near the opening. A large number of the
insulation blankets/bats, along with seat cushions from the upper aft troop
compartment were piled around the entrance to the stairs from the troop
compartment down to the cargo bay, plus scattered along the cargo bay floor
in the direction of the failed port hole/window. Seat cushions, mattresses
from bunks, & insulation bats/blankets from the upper front area were piled
against the exit stairs from the upper from lobe & along the cargo bay floor
toward the failed port hole/window. A few of the insulation bats/blankets
were blown out the failed port hole/window.

A/C being tested were instrumented to record/document test protocols as
appropriate. According to instrumentation on the A/C, at time of port
hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
seconds.

Factory Pressure Check on C-5's was 15 pounds, slightly over 1 atmosphere.
This was worked up to in stages. This incident occurred.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

"Ralph Nesbitt" wrote in message
m...

"Jeff Franks" wrote in message
...

Witnessed the result of "Port Hole Window" on the starboard side of a C-5
blowing out during "Initial Factory Pressure checks" on a new C-5". The
window itself went through the side of a "Tin Sided Building" ~ 200' from
where the window/port hole came from. A substantial number of the
insulation/batting blankets were torn from their normal place in the cargo
bay & piled on the cargo bay floor near the opening. A large number of the
insulation blankets/bats, along with seat cushions from the upper aft
troop
compartment were piled around the entrance to the stairs from the troop
compartment down to the cargo bay, plus scattered along the cargo bay
floor
in the direction of the failed port hole/window. Seat cushions, mattresses
from bunks, & insulation bats/blankets from the upper front area were
piled
against the exit stairs from the upper from lobe & along the cargo bay
floor
toward the failed port hole/window. A few of the insulation bats/blankets
were blown out the failed port hole/window.

A/C being tested were instrumented to record/document test protocols as
appropriate. According to instrumentation on the A/C, at time of port
hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
seconds.

Factory Pressure Check on C-5's was 15 pounds, slightly over 1 atmosphere.
This was worked up to in stages. This incident occurred.
Ralph Nesbitt
Professional FD/CFR/ARFF Type


This is not the same situation. First the preasurization was set to twice
what it will be in flight. Second the preasure dropped because the engines
were not pumping air in. Take a bicycle tire pump it up to 8psi (almost
flat) and then let the air out. This it the same preasure differential.

Mike
MU-2

"Mike Rapoport" wrote in message
link.net...

"Ralph Nesbitt" wrote in message
m...

"Jeff Franks" wrote in message
...

Witnessed the result of "Port Hole Window" on the starboard side of a
C-5
blowing out during "Initial Factory Pressure checks" on a new C-5". The
window itself went through the side of a "Tin Sided Building" ~ 200'
from
where the window/port hole came from. A substantial number of the
insulation/batting blankets were torn from their normal place in the
cargo
bay & piled on the cargo bay floor near the opening. A large number of
the
insulation blankets/bats, along with seat cushions from the upper aft
troop
compartment were piled around the entrance to the stairs from the troop
compartment down to the cargo bay, plus scattered along the cargo bay
floor
in the direction of the failed port hole/window. Seat cushions,
mattresses
from bunks, & insulation bats/blankets from the upper front area were
piled
against the exit stairs from the upper from lobe & along the cargo bay
floor
toward the failed port hole/window. A few of the insulation
bats/blankets
were blown out the failed port hole/window.

A/C being tested were instrumented to record/document test protocols as
appropriate. According to instrumentation on the A/C, at time of port
hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
seconds.

Factory Pressure Check on C-5's was 15 pounds, slightly over 1
atmosphere.
This was worked up to in stages. This incident occurred.
Ralph Nesbitt
Professional FD/CFR/ARFF Type


This is not the same situation. First the preasurization was set to twice
what it will be in flight. Second the preasure dropped because the
engines
were not pumping air in. Take a bicycle tire pump it up to 8psi (almost
flat) and then let the air out. This it the same preasure differential.

Mike
MU-2

Agreed.

The purpose of the pressure test in question is to assure structural
pressure integrity to 1 atmosphere above AGSL.

Hopefully all realize when referring to "Air Pressure" at altitude this is
an "absolute" pressure value inside the fuselage irrespective of ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

A/C pressure systems are set to operate from departure point. If set
manually from info provided by ATC this is "Unadjusted Barometric Presser"
read from an instrument at the base of the Tower, a specified height above
the ramp. Most modern commercial A/C are equipped with automatic systems
that capture relevant data upon command/that is reset for each flight.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

"Ralph Nesbitt" wrote in message
m...
Hopefully all realize when referring to "Air Pressure" at altitude this is
an "absolute" pressure value inside the fuselage irrespective of ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

This is incorrect, pressurization is the differential between ambient and
cabin preasure.

Mike
MU-2

A/C pressure systems are set to operate from departure point. If set
manually from info provided by ATC this is "Unadjusted Barometric Presser"
read from an instrument at the base of the Tower, a specified height above
the ramp. Most modern commercial A/C are equipped with automatic systems
that capture relevant data upon command/that is reset for each flight.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

"Mike Rapoport" wrote in message
hlink.net...

"Ralph Nesbitt" wrote in message
m...
Hopefully all realize when referring to "Air Pressure" at altitude this
is
an "absolute" pressure value inside the fuselage irrespective of
ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

This is incorrect, pressurization is the differential between ambient and
cabin preasure.

Mike
MU-2

Please reconsider your statement above as it applies to pressurization of
A/C cabins at altitude.

At altitude A/C cabins are like a pressure vessel. A/C cabins are
pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
pressure @ 11,000' ASL, in the cabin irrespective of altitude above 11,000'
ASL.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

A/C pressure systems are set to operate from departure point. If set
manually from info provided by ATC this is "Unadjusted Barometric
Presser"
read from an instrument at the base of the Tower, a specified height
above
the ramp. Most modern commercial A/C are equipped with automatic systems
that capture relevant data upon command/that is reset for each flight.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

"Ralph Nesbitt" wrote in message gy.com...


At altitude A/C cabins are like a pressure vessel. A/C cabins are
pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
pressure @ 11,000' ASL, in the cabin irrespective of altitude above 11,000'

Actually, 8,000' (at least in US certificated transports).

"Ralph Nesbitt" wrote in message
gy.com...

"Mike Rapoport" wrote in message
hlink.net...

"Ralph Nesbitt" wrote in message
m...
Hopefully all realize when referring to "Air Pressure" at altitude
this
is
an "absolute" pressure value inside the fuselage irrespective of
ambient.
When referring to air pressures at ground level the pressure reading
is
above unadjusted ambient barometric pressure.

This is incorrect, pressurization is the differential between ambient
and
cabin preasure.

Mike
MU-2

Please reconsider your statement above as it applies to pressurization of
A/C cabins at altitude.

At altitude A/C cabins are like a pressure vessel. A/C cabins are
pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
pressure @ 11,000' ASL, in the cabin irrespective of altitude above
11,000'
ASL.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

No, the cabin is not at a constant preasure above 11,000' (and the number
that you are looking for is 8,000') unless the rate controller is set to a
rate greater than the climb rate of the aircraft (which is never done). If
what you say were true then the cabin altitude would not climb with the
airplane above 11,000' (8,000') which it clearly does. If you doubt this,
go buy an altimeter watch and see for yourself. Or you could buy a
pressurized airplane.

Mike
MU-2

"Ralph Nesbitt" wrote

Hopefully all realize when referring to "Air Pressure" at altitude this is
an "absolute" pressure value inside the fuselage irrespective of ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
gages on the FE's panel. One was a simple altimeter that indicated the
cabin altitude at all times and the other, a differential pressure gage
that indicated the difference in pressure between outside and inside.
The maximum differential for those aircraft was around 8.6 psi. The only
way to determine the absolute pressure inside the aircraft would be to use
a graph to convert the altimeter indication to pressure.

Bob Moore

"Robert Moore" wrote in message
...
"Ralph Nesbitt" wrote

Hopefully all realize when referring to "Air Pressure" at altitude this
is
an "absolute" pressure value inside the fuselage irrespective of
ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
gages on the FE's panel. One was a simple altimeter that indicated the
cabin altitude at all times and the other, a differential pressure gage
that indicated the difference in pressure between outside and inside.
The maximum differential for those aircraft was around 8.6 psi. The only
way to determine the absolute pressure inside the aircraft would be to use
a graph to convert the altimeter indication to pressure.

Bob Moore

The protocols you reiterate above will translate to a ~ constant pressure of
12 PSI Gauge inside the cabin as the A/C moves through it's flight profile
above ~ 11,000'.
Ralph Nesbitt
Professional FD/CFR/ARFF Type