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| Bell Boeing V-22 Osprey |
Introduction :
The V-22 osprey certainly
doesn't look like anything we've ever seen before.
It looks frankly quite bizarre and it's a revolutionary piece of military hardware but it's been a bit of a bumpy ride for this bizarre and certainly beast of an aircraft.
The Bell Boeing V-22 Osprey is a tilt-rotor military aircraft made for US Forces, capable of both vertical
takeoff and landing VTOL and short takeoff and landing airstone.
The tilt-rotor refers to an aircraft that generates lift and propulsion using one or more powered rotors typically at the ends of fixed wings.
This is an aircraft that
has two modes : helicopter and fixed wing essentially acting as an
aircraft rather than a helicopter.
While there are
certainly other examples of tilt-rotor aircraft the size and power of the V-22 osprey places it truly in a league of its own.
The Need :
The failure of the operation
eagle claw in 1980 a plan to rescue the 52 hostages held captive in the US embassy in Tehran highlighted the need for a new long-range high-speed vertical
takeoff aircraft.
Despite first appearing in 1989, it was another eight years before their full introduction but even then the whole project seemed to be a work in progress as recently as 2015 the V-22 was still undergoing tests.
This has been an
aircraft with a catalogue of issues to overcome and costs which have eclipsed
initial estimates but whoever said that designing revolutionary forms of
transportation was ever quick easy or cheap certainly not the military the V-22 has required plenty of patience but it's certainly been worth it.
Operation eagle claw which took place between the 24th and the 25th of April 1980 was an utter fiasco the plan to rescue the hostages in Tehran didn't even get past its early stages and was certainly a long way from the Iranian capital.
Perhaps the most glaring
of the failures was the performance of the RH-53dc stallion helicopters three
of the eight helicopters experienced technical difficulties during the mission
heavily contributing to its failure which ended up costing the lives of eight
u.s marines and one Iranian civilian.
After such a debacle
there was a strong consensus that the US needed a major upgrade in terms of its
heavy lifting helicopters.
The joint service vertical takeoff landing experimental aircraft program jvx began in 1981 under the leadership of the US Army in December 1982.
Production :
A request for proposal
(RPF) was issued with aerospatial Bell helicopter, Boeing, vertol Gruman ,lockheed
and westland all interested in building this new helicopter these contractors
were asked to partner with each other with bell and boeing vertole joining
forces and submitting a modified design of the bell 15 prototype on the 17th of
february 1983.
Considering this was the only design ever received it wasn't a difficult choice for the American military here a contract was awarded to Bell-Boeing on the 26th of April 1983.
On the 15th of January 1985 the jvx aircraft was given a new name the V-22 osprey.
An osprey is a
fish-eating hawk widespread in the united states and indeed across every
continent except for Antarctica.
They're big powerful and they operate near water this name, therefore, seemed perfect for this new aircraft which had also taken the fancy of the US Navy.
By March 1985, the first six prototypes were under production with work split between Bell and Boeing.
Bell focused on the wing
nacelle's rotor drive system tail surfaces and aft ramp as well as integrating
the Rolls-Royce engines and performing final assembly.
Boeing took care of the
fuselage cockpit avionics and flight controls.
Full-scale development took a giant step forward on the 3rd of May 1986 with a 1.714 billion about 4 billion dollars today the contract for the V-22 signed by the US Navy.
But at this point all
four sections of the US military had placed orders for the V-22 osprey.
The V-22 made its public
bow in may 1988 and it looked like it would have a blossoming future from there
but things started to go wrong pretty quick firstly the army left the project
stating they needed to focus on more immediate programs while in 1989 the V-22 narrowly passed two senate votes which would have effectively gutted the
program but this was just the beginning of a messy squabble over finance that
highlighted both deep divisions within the US government and also the
astronomical costs that were being bounded around.
The department of
defense instructed the navy not to spend more on the V-22 with defense
secretary Dick Cheney trying in vain to defund the project between 1989 and
1992.
He was overruled by
congress but it was hardly a cohesive unit moving forward the Clinton
administration which arrived in 1992 seemed much more open to the V-22 and it
received the financial backing that it needed on march 2nd 1989.
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| Bell Boeing V-22 Osprey |
The first prototype took to the sky but only in helicopter mode.
Its first performance in fixed-wing mode came on the 14th of December 1989.
In December 1990 the third and
fourth prototypes took part in successful sea trials on the USS Wasp.
The fourth and fifth prototypes, however, both crashed between 91 and 92.
Following these two incidents, the V-22 saw several design changes to lower its empty takeoff weight reduce
production costs as well as generally simplifying the manufacturing wherever
possible.
This is a trend that seems to pop
up time and time again with the V-22, the next 10 years saw countless tests and
slight alterations.
The first of four low rate
initial production (LRIP) aircraft was delivered on the 27th of May 1999 and
sea trials were completed aboard the USS Saipan in January 1999.
LRIP the initial small quantity
units which are often used for testing and training in the military a way of
ironing out the creases before full-scale production goes ahead.
The V-22 was plodding along
painfully slowly and tragedy was just around the corner.
On April the 8th 2000 the V-22
carrying 15 marines along with its crew of four crashed in Arizona, killing all
onboard the cause of the crash was determined to be the rate of descent prior
to the V-22 entering an erratic role the aircraft was dropping at a rate of 609
meters 2000 feet a minute well above the recommended 243 meters 800 feet a
minute.
All V-22s were grounded as the crash was investigated but conclusions were ultimately made that the aircraft
itself was not to blame.
However, a report was written by the
department of defense director of operational test and evaluation stated
that the V-22 was not operationally suitable primarily because of reliability, maintainability,
availability of human factors and interoperability issues.
This was a truly damning verdict
it took another five years before the V-22 completed its final operational
evaluation in 2005.
But things were still not quite
done US navy air systems command began to work on an upgrade to increase the
maximum speed from 250 knots to 270 knots and to increase its helicopter mode
altitude from 3 000 to 4 300 meters.
By 2012, these upgrades appear to
have been completed and the V-22 landed and refuelled onboard the USS Nimitz.
In an evaluation in October 2012 and
performed cargo handling trials aboard the harry s Truman in 2013.
But by this point V-22s were
already being used in operations around the world.
The V-22 is unique so it's not
entirely surprising that it took so long to get it right the world's first production
tilt-rotor aircraft has two three-bladed pro protes located on the transmission
nacelles mounted on each wingtip and a turboprop engine the V-22 is of course a
little bit helicopter and a little bit of aircraft.
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| Bell Boeing V-22 Osprey |
However, while airborne
the nacelles can swivel forward 90 degrees to transform the V-22 into a
fuel-efficient higher speed turboprop aircraft.
Body of the aircraft is composed of composite materials a grouping of different materials with significantly different physical or chemical properties.
The rotors are also made
of composite materials and can be folded neatly in just 90 seconds.
When the aircraft needs
to be stored, the exhaust heat coming from the V-22's engine is so ferocious it
can damage flight decks, to get around this the naval air systems command
implemented portable heat shields to be placed under the engines while on decks.
This is seen as a
short-term fix and eventually decks will need to be redesigned with heat
resistant coating and passive thermal barriers.
Now when I say in the
air it's generally considered that one engine would not be enough to keep the V-22 hovering for any significant amount of time but it can still theoretically
function.
Specifications :
In September 2013 Rolls-Royce
increased the AE-1107c engine's power by 17 percent which would also improve
reliability in high altitude and high conditions.
Not only that but it
would boost the maximum payload limitations from 6000 to 8000 shaft horsepower.
They have a length of
17.48 meters and a width of 25.7 meters including rotors.
The V-22s have a capacity
of 24 seated troops or 32 troops floor loaded alternatively, it can carry 9070
kilograms of internal cargo or up to 6800 kilograms of external cargo using a
dual hook.
Is has a service ceiling
of 7600 meters and a range of 1 628 kilometers.
Now this is primarily a transport helicopter but it can still pack a punch if needed it can be armed with one 7.62x51 millimetre NATO M-240 machine gun or a 12.7-millimetre M2 machine gun on the rear loading ramp.
In 2009, half of the V-22s deployed to Afghanistan had bae systems as an interim defense weapon system
installed.
This remotely operated
gun turret system was used by the gunner to acquire targets through a separate
pod using colour television and forward-looking infrared imagery however its use
was limited because of its huge weight of 360 kilograms and the restrictive
rules of engagement during the conflict.
A roll-on roll-off
aerial refuelling kit is currently under development which would give the V-22 the ability to refuel other aircraft with Boeing first testing the kit on the
5th of September 2013.
Operations :
The V-22 osprey has been
used in numerous operations around the world by July 2008 a total of 3000
missions totalling some 5200 hours had been carried out by V-22s in Iraq.
They were mainly used for risky scouting operations and for transportation and though they were fired upon on numerous occasions, the US didn't lose a single one.
The first combat
operations came in Afghanistan in 2009 during operation Cobra’s Anger on the
4th of December 2009 in Helmand province by 2011 they had amassed a hundred
thousand flight hours throughout Afghanistan.
They have also
participated in combat operations in South Sudan and Yemen.
January 2010 saw V-22 participate in operation unified response after the devastating earthquake that
hit Haiti.
And in 2013 they were
deployed to the Philippines after typhoon Haiyan had swept through the area.
In 2014 they were
directed to Liberia to aid in the attempt to contain the Ebola outbreak in the
country.
They've carried
presidents, first ladies, generals and many more but perhaps one of the most
significant people the V-22 have ever carried was very much dead on the 2nd of May
2011 a V-22 landed on the aircraft carrier USS Carl Vinson its cargo that day
was the dead body of the man the united states had been searching for well over
a decade Osama bin laden his body as we know was buried at sea but it was just
another day for the V-22.
Conclusion :
No one would claim that
it's been an easy ride for the V-22 at a cost of about 68 million dollars per
aircraft you can see why there have been plenty of reservations along the way
it is a flawed genius which has needed countless tweaks and modifications along
the way to make it what it is we see today but despite its troubled path and frankly
eye-watering cost what has finally emerged is extraordinary and may well
fundamentally change how we view aviation the design of the tilt-rotor aircraft
has gone up to a completely different stratosphere the V-22 osprey part
aircraft part helicopter one very fast very agile revolutionary piece of
engineering.
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