Nathan Young wrote in message . ..
On Fri, 15 Oct 2004 10:05:26 -0700, "C J Campbell"
wrote:


"Dave" wrote in message
.. .

Halifax, Nova Scotia , - Canada...

A cargo 747, 7 lost...

Some news reports are saying that the 747 attempted an intersection takeoff
with 6000 feet of runway left, fully loaded with fuel and cargo for a flight
from Halifax to Spain. Can the 747 really do that?

This Boeing site
(http://www.boeing.com/assocproducts/aircompat/747.htm) lists tech
details like the takeoff rolls for a given weight. We need to know
what model of 747, the brake release weight, and the pressure altitude
to determine takeoff roll.

As an example though:
The -100,-200,-300 versions of the 747 show the takeoff distance to be
9500 feet @ sea level @ max gross (720,000 lbs)

To make a 6000ft runway, the plane needs to be 140,000 lbs lighter
(580,000lbs).

The numbers for the 747-400 are even higher (starting @ 6000 feet, and
going up from there). Which explains Denver's 16,000ft runway.

-Nathan


Nathan - A crew is required to calculate the balanced filed length
which provides sufficient runway for the plane to accelerate to V1,
lose an engine, and then stop using only brakes, with no reverse
thrust. The actual length required for a normal take-off is much much
less.

And as another poster noted, this was not a normal takeoff in that the
crew apparently over-rotated the airplane, resulting in the tailstrike
and diminishing the plan's performance.

It will interesting to learn more about this as the investigation
develops. My thoughts and condolances to those who loved the members
of the crew.

Blue skies

John