Scorpion readied for another starring role at Farnborough
03
ay, 2016 - BY: Stephen Trimble - Wichita
A production
version of the Textron AirLand Scorpion jet with a modified wing and landing
gear is coming together in the same Wichita facility where the demonstrator was
secretly constructed over an 18-month period three years ago.
Within
Cessna, the Textron subsidiary that designed and built the surveillance and
light attack fighter, the Scorpion’s home on the east side of town is known as
the “Glass House”, but few are allowed to see inside. It is here where Cessna
developed its most advanced designs, including most recently the CJ4 business
jet. The composite-skinned Scorpion twin-jet represents a more ambitious
gamble, offering a military fighter on the export market despite little
prospect of a near-term order from Cessna’s host government in the USA.
As the
project enters its fifth year, Textron AirLand is making preparations for a
lengthy production run of the Scorpion, assembling a supply chain and working
to unveil a surprise at the Farnborough air show.
During a 25
April tour, signs posted around the engineering offices touted a 30 June first
flight date for the production configuration of the Scorpion, leaving two
months to complete assembly and safety of flight testing on software and
systems. But that schedule grants perhaps just enough time for the
production-conforming aircraft to make a debut appearance at Farnborough, which
begins 10 days later.
For
Textron’s self-funded gamble to pay off, this production version may play the
deciding factor. The Scorpion demonstrator has flown displays at air shows,
participated in military exercises and offered back-seat rides to potential
customers from Asia to Latin America. So far, however, the demonstrator has not
attracted a launch order.
The USAF’s accreditation office, offering the service’s airworthiness stamp of approval to aircraft not in the military’s inventory, opened its doors on 4 April and early discussions with Textron AirLand are under way, says Dale Tutt, lead engineer for the Scorpion.
Several questions about the accreditation process remain, such as whether the USAF’s certification authority itself would accept an “accreditation” certificate or require further testing. But the Textron AirLand hopes to be ready to move beyond those questions by mid-June, allowing detailed planning to begin for the Scorpion’s accreditation testing, Tutt says.
Meanwhile, workers are making adjustments to the original Scorpion design. Textron AirLand rushed the Scorpion from design concept to first flight in less than 20 months. The production version allows them to refine the design of certain components. The main landing gear, for example, of the Scorpion demonstrator is an elaborate oleo strut design. It is being replaced with a simplified trailing link gear, removing 90kg (200lb) in the process, Tutt says.
Another change adds 4˚ of sweep to the outboard span of the wing leading-edge. The demonstrator revealed a centre of gravity slightly aft of the design intent, Tutt says. Increasing the sweep angle should correct the centre of gravity position while not affecting speed or manoeuvrability performance, he adds.
Other changes from the demonstrator design include the speed brake, which was bolted on to the top of the aft fuselage as an afterthought. The speed brake on the production version is designed to be flush with the fuselage skin, Tutt says.
More tweaks are being made beneath the skin. Cessna designed the Scorpion with a unique twin-keel hull, allowing the fuselage to accommodate a centerline payload bay. The original design allowed the Scorpion to fully retract a 15in-wide sensor turret assembly. Cessna changed the production design to store a 25in-wide sensor, such as the Sierra Nevada Gorgon Stare wide area surveillance system.
In the nose Textron AirLand is expanding optional payloads beyond the standard weather radar. The production Scorpion will have space reserved to instead house a multimode fighter radar, such as Northrop Grumman’s APG-68 fire control and synthetic aperture system.
Le Bourget 2015 - Per Gram
The list of
potential Scorpion customers is long, but their commitment level remains murky.
Textron AirLand has publicly displayed the aircraft all over the world,
including in Bulgaria, Chile (above, during the FIDAE air show),
Colombia, France, Romania, the United Arab Emirates and the UK. The
demonstrator aircraft offered a glimpse of the Scorpion’s capabilities but by
itself was not fully convincing.
It is a
familiar story in aviation. In the early 1980s, Northrop displayed the F-20
fighter demonstrator to foreign militaries but a lack of interest from the USAF
spooked other customers and the programme was cancelled.
Textron
AirLand president Bill Anderson insists the same lack of US sales for the
Scorpion is not a factor in discussions with foreign governments.
“They want
to fly the production-conforming airplane,” Anderson says.
The
Scorpion’s connection with Textron Aviation means that, unlike the F-20,
foreign buyers will have access to global support infrastructure set up for the
17,000 aircraft in service with Cessna and Beechcraft customers, he says.
Textron AirLand
Textron
AirLand had hoped to offer the Scorpion for the USAF’s Northrop T-38
replacement programme, but the T-X trainer performance requirements released so
far do not look promising. The USAF has not specified a supersonic aircraft,
but Textron AirLand’s interpretation of the proposed requirements imply an
aircraft with supersonic or near-supersonic performance.
But Textron
Aviation’s design team is not yet giving up on a run for the T-X contract. For
more than 60 years, Cessna and Hawker jet trainers have supported US forces,
ranging from the retired, tandem-seat Cessna T-37 Tweet to the T-1A Jayhawk, a
training version of the Hawker 400 twinjet. Textron AirLand is not ruling out a
bid for the T-X contract with a clean-sheet aircraft design, Anderson says.
Textron
AirLand’s independent bid depends on the next moves by the USAF. Along with
four other competing teams, Textron AirLand is waiting for the USAF to release
the first draft of the solicitation document, which should reveal details of
the programme’s requirements, funding and schedule.
USAF
officials have also talked about launching an OA-X programme to replace the
Fairchild Republic A-10, a fleet now scheduled for a controversial retirement
in fiscal year 2021. But the force's plans for OA-X remain too “vague” and
imprecise for Textron AirLand to comment on the Scorpion’s suitability,
Anderson says.
Likewise,
Textron AirLand received positive signals from US Naval Air Systems Command
last year, following a sales pitch based on using the Scorpion to offload
land-based training from the Boeing F/A-18 Hornet fleet. Textron AirLand
promises the Scorpion can operate for less than $3,000 per hour with a 98%
mission reliability rate. So far, the navy has revealed no path to acquiring
the Scorpion over the next six-year budget plan, Anderson says.
In the near
term, the best opportunity for sales is likely to come from the international
market. Textron AirLand designed the Scorpion primarily as an intelligence,
surveillance and reconnaissance platform, with the light attack mission a
secondary capability.
As the
company assembled a business case to launch the Scorpion demonstrator
programme, a Textron AirLand market survey counted a potential market for 2,000
aircraft, counting replacements for a global fleet of jet-powered Aero
Vodochody L-39s, Cessna AT-37s, Douglas A-4 Skyhawks and Sukhoi Su-25s. As
suppliers for the production Scorpion have come on board, they have performed
more recent surveys that validate the original figure, Anderson says.
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