Push to rush V-22 into war questioned
By BOB COX
Star-Telegram Staff Writer
With U.S. special forces preparing to go into Afghanistan
to hunt terrorists, it would seem this is just the kind of
campaign for which the V-22 Osprey was designed.
But some leading aerospace engineers and former combat helicopter
pilots say that if the V-22 is rushed into action, the aircraft
could pose a significant danger. And Undersecretary of Defense
Pete Aldridge said Tuesday that the V-22 will not be ready
for flight tests until April or May next year.
"It is my view it needs two years of flight testing before
we can answer the question of whether of not this is a reliable,
safe, operationally suitable aircraft," Aldridge told Bloomberg
News.
Even after nearly 20 years of development and $13 billion
in expenditures, critics say the V-22 still has serious, fundamental
safety problems that are being glossed over by the program's
backers.
"It's very premature to be thinking about using the V-22
in any operational situation, let alone in Afghanistan," said
J. Gordon Leishman, an aerospace engineering professor at
the University of Maryland's rotorcraft research center.
The V-22, Leishman and others say, seems to have basic flight
control problems that make it very difficult to fly in all
but the tamest conditions.
"It's a very unforgiving
airplane," a Defense Department official said, speaking on
condition of anonymity. "If you make a mistake, you die."
At the moment, the V-22 isn't flying anywhere. The dozen
or so production and test aircraft now in the hands of the
Marines, Navy and Air Force have been grounded since December
after two crashes in eight months that killed 23 Marines.
But last week, Rep.
Curt Weldon, R-Pa., a long-time supporter of the oft-troubled
V-22 program, said the problems that caused those crashes
are almost fixed and the aircraft could be ready for use in
30 to 60 days.
"That bird is ready to go, and we should get it up in the
air," said Weldon, chairman of the House Armed Services Committee's
subcommittee on military procurement.
Marine Commandant
Gen. James Jones also has been lobbying Congress, saying the
V-22 could be ready for action early next year if additional
funds were made available.
Rep. Kay Granger, R-Fort Worth, agreed with Weldon that "we
really do need it right now," but she also said it is important
that the V-22 be proven to be safe.
The V-22 is a joint project of Bell Helicopter Textron of
Fort Worth and the Boeing Co.'s helicopter division based
in Ridley Township, Pa., adjacent to Weldon's district. About
one-third of Bell's 6,000 Fort Worth-area employees work on
the program.
Almost since the V-22 was conceived in the early 1980s, its
backers have promised that the aircraft would be the ideal
tool for special operations missions. It would be faster than
helicopters and fly farther without refueling, enabling it
to take troops into remote and rugged locations.
The big selling point for the V-22 is its ability to take
off and land vertically like a helicopter and then, by rotating
its engines, fly with the speed of an airplane. That's also
the root of its problems.
Critics say that when the V-22 is being operated like a helicopter,
it has limited ability to maneuver and is highly susceptible
to rotor stalls and other flight problems that can result
in fatal accidents.
The V-22 "is a lousy helicopter. If you fly it outside the
envelope, it will bite you," said Leishman, using the aviation
term for an aircraft's flight limits. "And they don't yet
know what the envelope is."
Bell, Boeing, and the Navy don't agree with Leishman.
Company officials declined to be interviewed for this article,
citing possible lawsuits stemming from the crashes. Bell officials
provided a written document, compiled in cooperation with
the Navy and Boeing, that says the V- 22 is as maneuverable
as comparable helicopters and does not have a problem with
stalls.
The plane's critics, however, say that when the V-22 is flown
like a helicopter, the twin rotors can barely generate enough
lift to hold the heavy aircraft aloft, particularly when it's
loaded with fuel and troops. While hovering near the ground
or flying at low speeds the rotor blades cannot generate enough
extra lift to maneuver the aircraft
"If you try to maneuver like any military aircraft has to
do, you run into a very unsafe situation," said Alfred Gessow,
the founder and former director of the Maryland research center
and a former NASA researcher.
If a pilot in combat encounters enemy fire and tries to maneuver
sharply at low speeds, Gessow and others say the V-22 is likely
to stall with disastrous results. Gessow said that is an inherent
safety flaw: "You can't change some locknuts and make it go
away."
Bell disagrees. Its document states, "There is no `flaw'
in the V-22's prop rotor system."
The aircraft's critics, the document says, are basing their
opinions on inaccurate "information, premises, [and] reasoning."
The V-22 also has been criticized by an informal group of
active and retired engineers and helicopter pilots, many with
combat experience, who have been passing their observations
along to Pentagon officials and members of Congress.
The group calls itself the "Red Ribbon Panel," a reference
to the Pentagon's official "Blue Ribbon Panel" that reviewed,
and endorsed, the V-22 program this year.
Harry Dunn, a retired
Air Force helicopter pilot and engineer who acts as coordinator
for the group, said he and a number of former colleagues became
alarmed because they felt the Blue Ribbon Panel had ignored
the V- 22's lack of maneuverability and propensity to stall.
"There was not a single person on that panel who knew anything
about helicopters," Dunn said.
The panel's scientific adviser, Eugene Covert, a professor
emeritus of aerospace engineering at MIT, declined to comment
on V-22 stall and safety issues for this article.
Although they differ on exact details, the V-22 critics agree
that the Osprey's aerodynamic problems stem from its basic
design - namely its rotors, which also serve as propellers.
"What you have is a severely compromised aircraft that is
neither fish nor fowl," said Gessow, whose textbook, `Aerodynamics
of the Helicopter,' was first published in 1952 and is still
considered one of the leading texts.
Although the three blades of each rotor are 19 feet long,
huge by comparison with the propellers on a turboprop airplane,
they're small compared with those on a similar-size helicopter.
As a result, critics say, in helicopter mode, the V-22's
rotors have to work much harder than those on a helicopter
to generate the same level of force. The blades also have
a much higher degree of twist than those on a helicopter,
which, under some flight conditions, creates nasty air flows
that make it easier for the V-22 to stall, or lose lift.
The V-22's side-by-side, wing-mounted engine design exacerbates
its stall problem, the critics say. With the engines and rotors
at the end of the wings it's almost inevitable, they say,
that when the aircraft gets into troublesome flight conditions
one rotor will stall, causing the aircraft to roll.
Bell disagrees with the criticisms.
"The people making these assertions lack the requisite knowledge
of the aircraft, its rotor system and its performance envelope,"
the document provided by the company states.
Bob Cox, (817) 548-5534
rcox@star-telegram.com
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