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| A-4 SkyHawk |
Without alarm being given, a small formation of
apparatuses emerges at low altitude and moved straight towards the two
buildings practically without defense which poured their loading of
troops and equipment close to Fitzroy. Two of the planes were
for Sir Tristram and three for Sir Galahad, which, touched by direct
impacts of bombs, suffered serious damage and recorded important
losses in human lives. The events of June 8 1982 reported in the
preceding lines illustrate well the effectiveness of a hunter low-size
bomber whose prototypes had been ordered by US Navy almost thirty
years before. Appreciated by its pilots for its qualities as
regards handiness, Skyhawk is not any more one plane modern with the
clean direction of the term. But a constant up to date
handing-over of its equipment and its armaments still enables him to
appear in the units of first line of several air forces, which
estimate at their right value his versatility and its costs of
maintenance relatively low. Of A-4 of second hand are about to
undergo transformations which will enable them to undoubtedly remain
in service until the beginning of the next millenium.
Like many other flying machines, Skyhawk draws the secrecy from
its longevity not of its sophistication, but well of its simplicity.
The specifications emitted by US Navy claimed the realization of
a plane of attack dejour embarked single-engined aircraft able to
carry out missions of brought closer support, bombardment and
prohibition with conventional armaments or nuclear. Led by
engineer Ed Heinemann, the team from Douglas in charge of the design
of the apparatus worked with the idea to reduce the masses in all the
measurement of the possible one. All the efforts had been made
to make savings in weight. The development of the plane
proceeded according to traditional working methods, while the adopted
equipment had for a long time proven reliable. This way of
proceeding guaranteed to arrive at relatively low cost.
Indicated A4D until the time when the denominations of use in
the three American armies were unified (1962), the prototype of
Sky-hawk accomplished its initial flight on June 22, 1954, above El
Segundo. Conceived to operate without escort of hunting, it gave
the proof of some of its capacities while becoming the first plane of
attack to the world to hold the record speed on circuit of 500 km,
with 1 118,700 km/h. In October 1956, after one period of
development free from major problems, the first version of series
entered in service US Navy.
February 27, 1979, the 2 960e and last specimen of Skyhawk was
taken into account by the US Marine Body with the factory of Palmdale,
where 342 other specimens of the same series had been assembled.
Thus ended the longest manufacturing process to which lieuun
American military aircraft gave. In the interval, various
programs of modernization had been launched and concluded. The
first orders with export did not intervene before the middle of the
Sixties, time to which Skyhawk made its appearance on the theatre of
operations of Southeast Asia. And the construction simple design
of the apparatus constituted the principal reason this success outside
the United States. The cell of A-4 is made of three principal
subsets: aerofoil, before and back of the fuselage. Of
entirely metal semi-monocoque design, the fuselage comprises a
detachable former point in which is the whole of the electronics
components of edge, the communication systems and the systems of
identification. The maintenance of the plane is easy, and the
cockpit was designed so that the pilot can fill his task with the
greatest possible effectiveness. The two elements of the
fuselage are solidarized between them only by six bolts, which makes
easier the changes of engine much. The vertical stabilizer is
built completely with the back subset, and the air-brakes, ordered
hydraulically, are installed on the sides of the fuselage behind
trailing edge of the wings.
Dimensions of the aerofoil are so restricted that the recourse
to a mechanism of retraction was not essential to allow the storage of
the apparatus in the hangars of the aircraft carriers, which
constitutes as many economies as regards weight. The robust
landing gear with which Skyhawk was provided does not have a system of
emergency lowering but can simply be descended and locked by gravity.
The first versions of A-4 were propelled by the turbojet Wright
J65, alternative produced under licence of Armstrong-siddeley
Sapphire. The A-4A had an engine providing a push of 3 495 kg,
while the A-4B and C profited from 3 855 kgp. As for the A-4E,
it comprised Pratt & Whitney J52 of 3 855 kgp, whose push was
increased to 4 220 kg on A-4 F the A-4M Skyhawk II, which made its
appearance in 1970, was equipped with a brake chute, of a redrawn
vertical stabilizer and a modified canopy, the push of its engine
being of 5 080 kg.
Skyhawk American
The current contribution of Skyhawk to the defense of
the United States is confined with the only field of the drive and the
reserves. About thirty formations of US Navy and US Marine Body
still fly on various models of this apparatus.
The oldest version still in service, the A-4E comprises two
additional pylons of carrying of load and a system of navigation
(Doppler, TACAN and altimeter radar) more modern than that of its
predecessors. Having a capacity of in-flight refueling, it is
able to carry air-to-surface missiles Martin AGM-12 Bullpup and has of
equipment of bombardment and an autopilot more advanced than those of
the A-4C. The pilots who operate on A-4 F profit from an
improved avionics, installed in a dorsal careenage in form of bump, a
better protection against the shootings come from the ground and, for
the first time on Skyhawk, of an ejector seat zéro-zéro. While
assembling a second seat under a canopy of greater dimensions, the
American firm carried out the TA-4 F, from which the deliveries began
in 1966. Thanks to its more powerful engine, the A-4M posted, at
the moment when it entered in service, of the spectacular performances
compared to the preceding versions. Having a climbing speed
higher of almost 50 % than that of A-4 F, it was equipped with a radar
of follow-up of ground APG-53A, with a power station of inertial
navigation ASN-41, with a collimator high head Elliott 56 and various
other equipment which made it possible to increase its operational
effectiveness of almost 30 %.
The A-4M can carry the majority of the armaments
appearing in the panoply of the US Marine Body, including the bombs Mk
81 and Mk 82 respectively of 113 and 227 kg, of the guns out of
nacelles, of the torpedes, as well as baskets Zuni rocket or Mighty
Mouse respectively of 127 and 69,85 Misters Moreover, two guns Colt Mk
12 of 20 mm can be placed in the roots of wings, and various equipment
of electronic countermeasures is installed outside the apparatus in
order to supplement those which are inside. The points of
fastener under fuselage can receive loads of 1 590 kg, those which are
under the sections of the interior wings 1 020 kg, and those of the
external panels of aerofoil 454 kg. For a mission of support
brought closer typical to 240 km leurbase, the planes of the USMC
carry 1 815 kg of armaments, the capacity by carburizing intern (3 030
1) whom can more than be doubled by the addition of three tanks of 1
135 1 each one hung under the fuselage and the interior panels of
aerofoil (the passable distance in convoying can thus reach 3 220 km).
The OA4M, which is useful in three Headquaters & Maintenance
Squadrons, is intended for the missions of advanced air control.
The TA-4J forms a great part of the fleet of the planes of drive
of US Navy, and it will remain there to the operational service
entrance of BAe/McDonnell Douglas T-45 Goshawk. Identical to the
TA-4 F of the USMC, the TA-4J however has an engine J52-P-6 of 3 855
kgp and is deprived of some tactical equipment, in particular of 12
fire control system of the missiles. Produced starting from the
TA-4 F, this apparatus is used by seven will squadrons Naval Air
Training Command like by ten units of drive and operational
transformation. Among the other alternatives employed Navy spoke
appears A-4 F, which was useful, then was replaced by the F/A-18, in
the patrol of presentation of Blue Angels, and the EA-4 F of drive to
the electronic countermeasures.
Of the eight other countries which acquired of Skyhawk, only
Argentina and Australia tried to use the apparatus starting from
aircraft carrier. The Argentinian navy having ordered the
sending with the scrap of the only building of this type of which it
laid out, the embarked planes on board this last were sold. The
Argentinian air force was the first to sign with Lockheed Aircraft
Service Co (LASCo) a bearing contract on the setting with standards
A-4P of fifty of its A-4B and twenty-five of its A-4C, this operation
including the installation of a sight Ferranti ISIS D126R.
Skyhawk that the Argentinian navy used during many years came
from the setting to standards A-4Q of sixteen A-4B for their loading
on the aircraft carrier Veinticinco of Mayo, sixteen other
machines being acquired at Israel. Able to carry air-to-surface
missiles Bullpup and AIM-9 Sidewinder, this version did not draw from
it any during the operations of 1982 against Great Britain.
Skyhawk Israelis
On the other hand, Skyhawk acquired by the Hebrew State
were used in an intensive way in the wars which upset the Middle East
during the Sixties and seventies. The Israeli air force took
into account 244 single-seaters and 24 two-seaters of this type, from
of which A-4H, A-4N, TA-4H and J as well as A-4E coming from US Navy.
These planes made the object of successive modernizations, the
modifications made locally having consisted in the assembly of guns
DEFA of 30 mm instead of weapons of 20 mm and in the installation of
an exhaust nozzle lengthened in order to reduce the thermal signature,
and, therefore, the vulnerability of the apparatuses to the infra-red
homing head missiles.
The other user of Skyhawk in this area of the world is it, which
received a certain number of these planes in 1977-1978, at the one
period time of tension with Iraq. These machines, which were
only useful very little, were put on sale recently.
The Pacific of South-west constitutes another zone of activity
of Skyhawk. The air force of the republic of Singapore obtained
a significant number of these apparatuses, the first order going back
to 1972, where a market of forty A-4S, carried out starting from A-4B
of US Navy, had passed to the United States. Having received the
local denomination of Skywarrior, these planes were modernized by the
LASCo firm, which proceeded to a hundred modifications: adoption
of an engine J65-W-20 of 3 675 kgp, of sight Ferranti a calculator,
two Aden guns of 30 mm, spoilers and of a brake chute, in particular.
A version TA-4S, with certain operational capacities, was also
produced; it is different from the American models of drive by
its two separate cockpits and its lengthened fuselage of 0,71 m.
In 1982, Singapore Aircraft Industries carried out the first of
the forty specimens of A-45-1 Skywarrior, developped at the point
starting from A-4C, and of the eight units of the TA-4S-1, coming from
A-4B. These machines are characterized by their modernized
avionics and reinforced pylons of aerofoil. Moreover, two of
them ontété equipped with the dual flow jet engine General Electric F404,
which must be installed in the future more or less near on the forty
and one planes to this type in service in Singapore.
The State close to Malaysia started to be equipped with A-4PTM
as from December 1984, the work of conversion being undertaken by
Grumman with Saint Augustine, in Florida. The machines taken
into account by the local air force come from A-4C and A-4L (this last
version consisting of a A-4C equipped with the avionics of A-4 F), but
the operations of transformation less important than will be envisaged
because of various financial problems. As for Indonesia, it
acquired of fourteen A-4E and two TA-4H of drive at Israel in 1979;
one second unit was formed in 1985.
Always in service
New Zealand obtained a squadron equipped with A-4G and TA-4G in 1968, in order to use it in missions of anti-ship fight and air defense, in this last case with air-to-air missiles AIM-9H Sidewinder. The beginning of the Eighties, Royal New Zealand Air Force, planning to replace these apparatuses, carried out the evaluation of General Dynamics F-16 Fighting Falcon, McDonnell Douglas F/A-18 Hornet and Northrop F-2(Tigershark. In the final analysis, the New Zealand ones took the resolution to buy in Australia eight A-4G and two TA-4G, which are to be given to new and must come to enlarge their fleet of Skyhawk. The work of modernization, which still continues at the current hour, concerns the adoption of new electronics components, an interior configuration of the cockpit modified, ejectors of thermal lures and spangles, and of a brake chute. Thereafter, these machines could be equipped with a radar of maritime surveyance (probably of Ferranti Red Fox) and F404 engine. Thus, thirty-five years after its design, Skyhawk would give rise to a new plane of attack able to compete with some of the apparatuses of the same category offered at the present time on the market.
