ASHINGTON, Sept. 19 — Seeking to counter assertions
that the nation's nuclear plants are vulnerable to attacks
like the one on the World Trade Center, 19 prominent nuclear
experts have concluded that a reactor containment building
could easily withstand the force of a jetliner crash.
But the federal laboratory that conducted a major test
cited by the experts says its experiment was not meant to
demonstrate anything about reactors' structural soundness.
The 19 experts, many of them retired, work or worked at
universities or companies that build or operate reactors. In
an article on Friday in the journal Science, they dismiss
fears voiced by opponents of nuclear power that the nation's
reactors are vulnerable to a terrorist attack.
"We read that airplanes can fly through the reinforced,
steel-lined 1.5-meter-thick concrete walls surrounding a
nuclear reactor," the article says, "and inevitably cause a
meltdown resulting in `tens of thousands of deaths' and `make
a huge area uninhabitable for centuries,' to quote some recent
stories." But, they add, "no airplane regardless of size, can
fly through such a wall."
The article says the scenario "was actually tested in 1988
by mounting an unmanned plane on rails and `flying' it at 215
meters per second (about 480 m.p.h.) into a test wall." The
engines penetrated only about two inches and the fuselage even
less, according to the article.
But the relevance of the test, conducted at Sandia National
Laboratories, has long been in dispute. People who opposed
nuclear power before Sept. 11 pointed out that the test wall
moved several feet; the movement reduced the damage by
absorbing some of the force of impact.
At Sandia, a spokesman, John German, said the point of the
test was to move the wall, as a way to measure the impact
forces. The test was sponsored by the Muto Institute of
Structural Mechanics Inc., of Tokyo, as a preliminary step in
building a computer model of such impacts, but the Japanese
decided not to sponsor the next step, Mr. German said.
Asked if it showed that a plane could not penetrate a dome,
he said, "We've been trying like heck to shoot down this
Mr. German said: "That test was designed to measure the
impact force of a fighter jet. But the wall was not being
tested. No structure was being tested."
The nuclear experts contend that the test makes their point
nevertheless. The opponents of nuclear power have argued that
the plane in the Sandia test, an F-4 Phantom, weighs far less
than a jumbo jet.
But James Muckerheide, a nuclear engineer who is the
co-director of the Center for Nuclear Technology and Society
at Worcester Polytechnic Institute, on whose work the authors
relied, said in an e-mail response to a reporter's question
that penetrating a reactor containment building would take far
more than an airliner. Compared with the F-4, Mr. Muckerheide
said, "a large passenger aircraft is a slow, empty, tin can."
"The mass of the aircraft can put a heavy compression load
on the containment structure," he said, "but it has negligible
The containment building can withstand huge compression
loads, he argued. The fact that the block in the Sandia test
moved had a trivial effect, Mr. Muckerheide said.
Whether a containment building is the soft spot of a
nuclear plant is also not clear. Most of the radioactivity in
a power plant is in the spent fuel pool, which, critics note,
is usually in a building that is far less sturdy.
The Nuclear Regulatory Commission is conducting an
engineering analysis of the vulnerability of power plants to
aircraft attack, Sue Gagner, an agency spokeswoman, said. "If
warranted by the ongoing detailed analysis, we will consider
changes," Ms. Gagner said.
Articles in Science, like those in many scientific
journals, are reviewed before publication by experts not
connected with the authors. But the magazine's editor in
chief, Donald Kennedy, said that if there was a difference
between the authors and the group that performed the
experiment, "they're going to thrash it out in our letters
column, and we'll let them do it."
The magazine is published by the American Association for
the Advancement of Science.