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Canadian Aerospace
— Comparisons — Stretched C-130J Hercules |
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C-130J – Bigger is Better or Magic Mushrooms?
In 2005, the British offered to lease C-130J Hercules to Canada. This offer of short-bodied
Hercules was derided in the press – an unnamed industry source claiming that the "...last
thing Canada needs is short aircraft... Everyone [else] is buying the long [C-130J] because it has the range,
payload, and speed." That claim went unchallenged at the time despite being illogical. Obviously, a mere fuselage
stretch cannot endow the 'J-30 Hercules with magical powers. So, what is the
story ?
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Short Stuff – Standard Fuselage C-130 Hercules
The standard model Hercules – whether an existing Canadian Forces CC-130E/CC-130H or the
new-build C-130J – has a 29.8m long fuselage, translating into a cargo hold floor
12.5m long (less the ramp) of which 12.19m is unimpeded. The empty weight for a C-130J is 34275 kg to which is added
20819 kg of fuel (25552 litres) plus an additional 8506 kg (10440 litres) of fuel in two external wing tanks.
Power is provided by 4 x 3424 kW AE 2100 turboprop engines which give the C-130Js an economical cruising
speed of 628 km/h.
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Stretch – Long Fuselage C-130 Hercules
The C-130J-30 is the latest 'stretch' model Hercules. Two extra fuselage sections are
inserted – adding 4.6m to standard length. The C-130-30 fuselage is 34.37m long. The cargo hold floor is
17.05m long (less ramp) of which 16.76m is unimpeded. The empty weight for the C-130J-30 rised to 35966 kg or
1691 kg more than the 'short' Hercules. The rest of the airframe remains the same. There no
increase in lift or engine power.
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"...Because I am so dwarfish and so low?" or a case of Cui Bono?
So, the 'stretch' C-130J-30 Hercules carries over a tonne and a half of extra airframe weight using the same
engine output as its 'short' stablemate. So much for claims of higher speed and greater range. And payload? A
longer cargo hold allows 'J-30s to carry a heavier payload but only by trading fuel weight for
cargo over a reduced range. More power makes C-130J-30s inherently superior to earlier
stretched Hercs, not to 'short' C-130Js.
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With the 'J model Hercules' more powerful engines, a C-130J-30 will likely run out of internal
space before exceeding its payload weight limits. When hauling cargo from airport to airport, this is an
advantage. But there's a downside. Stretch Hercs have a long rear overhang. If a pilot
'rotates' too quickly, the Hercules' extended rear fuselage 'ground scrapes'.
Usually this results in little more than a shower of sparks along a paved runway. However, the inability to rotate
as fully as a 'short' Herc does limit the C-130J-30s' value in rough field operations. And
CF 'Js are being bought for tactical airlift. Nevertheless, a contract was signed with Lockheed Martin
for the purchase of 17 'stretched' C-130J-30
Hercules [1] on 20 Dec 2007. [2]
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[1] For some reason, this contract signing wasn't announced until 16 Jan 2008. The initial contract covered only
the $1.44B purchase price for the 17 CC-130J-30 Hercules aircraft. That contract was to be followed by a
separate In-Service Support contract issued in 2009 (finally emerging on 18 Dec 2009 as a $723M contract amendment
with Lockheed Martin covering ISS for a 6 year period with optional renewals).
[2] This outcome of the Harper Conservative government's Airlift Capability Project-Tactical (ACP-T ) delayed
the procurement contract for a CC-130E/'H replacement by two years. The Martin Liberal government signed a contract
to buy 16 C-130Js (under its Tactical Airlift program) in Nov. 2005. This contract was cancelled by the incoming
Conservatives who denounced the contest as being unfairly skewed in favour of the C-130J. Ironically, the same
accusation was made for the Conservative's ACP-T contest. The real differences lay in money spent. The Liberal
contract was for $4B-to-$5B including a 20-year ISS contract. The Tory deal gained an additional airframe while cutting
the ISS contract into more manageable chunks – potentially more expensive over time but also encouraging a
shorter 'J-model service life.
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