slapfaan
15th Mar 2003, 13:56
Why the Concorde really crashed
Interesting piece on French Concorde accident:
From Continental Airline Pilot
We all also know that the Concorde crashed because it hit a metal strip
dropped from a CAL DC10 that departed from the runway just prior to the
Concorde's departure.
Right?
Wrong?
I prefer the Swiss cheese theory of accidents where the holes line up in
the various barriers to prevent accidents. When they do line up there is
an accident, over the Boeing chain of events.
Hole number one: The airplane had been in maintenance prior to this
flight and maintenance kinda sorta forgot to put a critical spacer in
the LMLG (Left Main Landing Gear) truck. ( we will get to this later).
Hole number two: The airplane is sitting at the gate. It is a few pounds
over gross, roughly 16,000 lbs. and the CG (Center of Gravity)is near
the aft limit.
Hole number three: The V1 (Velocity 1) speed for the weight is 199
knots. Now we get to the runway and off we go. As the airplane
accelerates it begins pulling to the left. Oh yes, the spacer was there
to keep the trucks from swiveling.
V1 is called Decision Speed. Above this speed it may not be possible to
stop the aircraft on the runway in the event of a Rejected Take Off (RTO.)
Hole number four: As they barrel down the runway the airplane's LMLG
hits a runway edge light stantion. Guess where the stantion goes? You
got it...right into the left fuel cell and punctures it and starts a
fire. Serious, but salvageable. Now you ask, "Why didn't the captain
just abort the takeoff?"
Hole number five: Sitting on a taxiway waiting to cross the runway is a
747 with the French president and his wife aboard. The captain now has
a choice. He can try to abort and perhaps plow into the 747 or he can
try to fly.
Hole number six: He decides to fly and rotates at 188 knots, 11 knots
below V1.
Hole number seven: So now you are having a really bad hair day. You are
in a burning, over gross airplane with the CG going farther aft by the
second because of the fuel loss, you are behind the power curve big time.
What can make the day worse? (By the way, for all intents and purposes,
they were already dead before the next, "Ah ****").
Hole number eight: The friendly, helpful flight engineer, on his own,
without consulting the captain, decides to shut down an engine he
THOUGHT was on fire. Now your bad day really is as bad as it gets: the
airplane is on fire, it's behind the power curve anyway and now you have a good
engine shut down when you are below VMCGAir (Velocity Minimum Ground).
The airplane rolls over on its back and crashes into a hotel. (VMCG,
which stands for Minimum Control indicated airspeed - Ground, is the
minimum speed (Velocity) at which the pilot can maintain directional
control of the aircraft with one engine suddenly becoming inoperative
during the takeoff roll, with the use of aerodynamic controls only).
Now you know why we don't fall in love with theories or jump to
conclusions based on initial assessments. Blaming the accident on the
CAL DC-10 was the easy way out. That makes it someone else's fault.
As Paul Harvey would say, "And now, you have the rest of the story"
Interesting piece on French Concorde accident:
From Continental Airline Pilot
We all also know that the Concorde crashed because it hit a metal strip
dropped from a CAL DC10 that departed from the runway just prior to the
Concorde's departure.
Right?
Wrong?
I prefer the Swiss cheese theory of accidents where the holes line up in
the various barriers to prevent accidents. When they do line up there is
an accident, over the Boeing chain of events.
Hole number one: The airplane had been in maintenance prior to this
flight and maintenance kinda sorta forgot to put a critical spacer in
the LMLG (Left Main Landing Gear) truck. ( we will get to this later).
Hole number two: The airplane is sitting at the gate. It is a few pounds
over gross, roughly 16,000 lbs. and the CG (Center of Gravity)is near
the aft limit.
Hole number three: The V1 (Velocity 1) speed for the weight is 199
knots. Now we get to the runway and off we go. As the airplane
accelerates it begins pulling to the left. Oh yes, the spacer was there
to keep the trucks from swiveling.
V1 is called Decision Speed. Above this speed it may not be possible to
stop the aircraft on the runway in the event of a Rejected Take Off (RTO.)
Hole number four: As they barrel down the runway the airplane's LMLG
hits a runway edge light stantion. Guess where the stantion goes? You
got it...right into the left fuel cell and punctures it and starts a
fire. Serious, but salvageable. Now you ask, "Why didn't the captain
just abort the takeoff?"
Hole number five: Sitting on a taxiway waiting to cross the runway is a
747 with the French president and his wife aboard. The captain now has
a choice. He can try to abort and perhaps plow into the 747 or he can
try to fly.
Hole number six: He decides to fly and rotates at 188 knots, 11 knots
below V1.
Hole number seven: So now you are having a really bad hair day. You are
in a burning, over gross airplane with the CG going farther aft by the
second because of the fuel loss, you are behind the power curve big time.
What can make the day worse? (By the way, for all intents and purposes,
they were already dead before the next, "Ah ****").
Hole number eight: The friendly, helpful flight engineer, on his own,
without consulting the captain, decides to shut down an engine he
THOUGHT was on fire. Now your bad day really is as bad as it gets: the
airplane is on fire, it's behind the power curve anyway and now you have a good
engine shut down when you are below VMCGAir (Velocity Minimum Ground).
The airplane rolls over on its back and crashes into a hotel. (VMCG,
which stands for Minimum Control indicated airspeed - Ground, is the
minimum speed (Velocity) at which the pilot can maintain directional
control of the aircraft with one engine suddenly becoming inoperative
during the takeoff roll, with the use of aerodynamic controls only).
Now you know why we don't fall in love with theories or jump to
conclusions based on initial assessments. Blaming the accident on the
CAL DC-10 was the easy way out. That makes it someone else's fault.
As Paul Harvey would say, "And now, you have the rest of the story"