美 해군의 무인정찰기, RQ-4N BAMS 개발 소식...

 

AW&ST 紙에 8월 23일字로 소개된, Northrop Grumman 社가 개발 중인 美 해군의 광역해상감시 고고도무인정찰기 RQ-4N

BAMS (Broad Area Maritime Surveillance) 관련 기사를 소개합니다.

 

BAMS 는 美 공군용으로 개발되고 있는 Global Hawk Block 40 를 기반으로 개발되고 있는 해상감시체계 이며, 아래 기사에

의하면, 美 공군이 Global Hawk 개발 과정에서 겪고 있는 시행착오와 이로 인한 비용증가 요소를 美 해군이 사전에 충분히

인지하고 대비하고 있다는 내용의 기사입니다.

 

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Risk Avoidance

Navy BAMS vehicle, sensor work incorporate hard-learned lessons from USAF Global Hawk

Aviation Week & Space Technology, 08/23/2010

Author : Amy Butler

 

Just over one year into the contract to develop a new U.S. Navy maritime surveillance aircraft, service officials are preparing for a critical design review in February and laying plans to avoid the same technology pitfalls of building a high-flying unmanned aerial system (UAS) now plaguing the U.S. Air Force.

 

The Broad Area Maritime Surveillance (BAMS) program, an $11-billion project to field 68 high-altitude UAS, expects to conduct its first flight in Fiscal 2012, says Jennifer Clarke, the Navy’s BAMS program deputy director.

 

Northrop Grumman won the $1.16-billion contract in April 2008 to develop BAMS, including two developmental vehicles for the Navy. A third developmental vehicle will be built, but the company will retain ownership of it, says Steve Enewold, Northrop’s BAMS vice president. BAMS is being designed to provide intelligence on surface shipping targets; together with the 737-based P-8 being built by Boeing, the new aircraft will replace the Navy’s aging P-3 fleet.

 

The BAMS UAS is being built on the Air Force Global Hawk Block 40 platform, including thickened skins and spars on the wing to allow the UAS to transit turbulent air over the littorals, Enewold says. While the Air Force system carries the Northrop Grumman/Raytheon Multi-Platform Radar Technology Insertion Program (MP-RTIP) side-looking active, electronically scanned array (AESA) radar, BAMS will employ the Multi-Function Active Sensor (MFAS). It is a 360-deg. mechanically steered AESA based on a special project funded through the Office of Naval Research.

 

BAMS will also use an Automatic Identification System (AIS) shipping tracking capability and a nose mounted air-to-air AESA to provide a situational awareness capability. “It is the first step in providing a due-regard capability in hopes of getting to an autonomous sense-and-avoid,” system, Clarke says. “Once we can get [due regard] solved for the big platforms, then let’s work on making the solution smaller” for other UAS. BAMS will also carry the Raytheon MTS-B electro-optical/infrared sensor, full-motion video system carried by the Predator fleet, as well as an electronic support measures (ESM) system for radio-frequency monitoring.

 

All of these elements are wrapped into the Northrop Grumman BAMS contract managed by a single office at Naval Air Systems Command. This management approach resulted from difficult lessons learned by the Air Force on the Global Hawk. In that program, the Air Force Aeronautical Systems Center in Ohio oversees the airframe development while the Electronic Systems Center is handling the previously turbulent MP-RTIP work. The two timelines didn’t marry well, and the program is over budget with deliveries expected late. Also, Air Force officials were issuing too many undefinitized contract actions (UCAs) in order to keep work flow moving, sparking concern by some in Congress. UCAs are used to allow a contractor to start work without defining the contract price, which is usually set at a later time; the upshot is that if these pile up, accounting for a program can be problematic.

 

“We are learning from everyone else’s challenges,” Clarke says. “If we see a problem that they are having we are going to go triple check and try and avoid that same problem.” She adds that the Navy has taken measures to allow for the time needed to get and approve proposals from Northrop (Air Force officials claimed the company took too long to build proposals). The Office of the Secretary of Defense is also conducting preliminary meetings to assess whether Global Hawk is at risk for a second breach of the Nunn-McCurdy statute, which mandates a review of over-budget programs. Much of the cost growth, however, includes items such as depot work and spares never included in the original Air Force program budget. David Van Buren, the Air Force’s top procurement official, has upbraided Northrop for cost and contracting problems.

 

“We’ve had a very good experience with Northrop,” Clarke says, unlike Van Buren. “It [the program] is managed out of [an office in Bethpage, N.Y.], which has a strong systems engineering background.”

 

To avoid surprises, Navy officials obtained an independent assessment from experts at the MIT Lincoln Laboratory on Northrop’s modeling for the MFAS sensor, and Clarke says the models from both are “very close.” Also, the Navy decided upfront to use a leased Gulfstream G-II as a surrogate aircraft for early MFAS flight testing, in advance of an available UAS. During the Global Hawk development the Air Force added Northrop’s high-flying Proteus as a surrogate asset to work out software problems with the MP-RTIP.

 

Another challenge for the Air Force was the result of a decision to embrace spiral development for several Global Hawk blocks. In parallel, work on three key sensors was undertaken, with a plan to introduce different capabilities on various Global Hawk blocks as they matured. The result, however, has been a testing bottleneck at Edwards AFB, Calif., and a delayed in-service date. Navy officials, though eyeing a communications relay capability and sophisticated signals intelligence payload for future increments, are now focused on the baseline design.

 

The Navy has also been experimenting with a Global Hawk Block 10 (employing the baseline Air Force Integrated Sensor Suite EO/IR payload outfitted with maritime modes and AIS) to patrol shipping over the Arabian Sea and Strait of Hormuz for more than one year (see p. 49). “From a cultural integration perspective, it has given the [maritime patrol and reconnaissance forces] an opportunity to have a persistent asset and figure out how best to use that,” Clarke says. Enewold says the demonstrator is providing “as much as 50% of the work in terms of maritime surveillance” in that area. “The range and persistence of the BAMS demonstrator is a surprise to everyone in the theater,” Enewold adds. “I don’t think there was an appreciation of what persistence and range really do for us.”

 

When BAMS is fielded, the likely operational concept is to use existing intelligence for a baseline. BAMS would then update this picture with AIS and check targets using the MTS-B and/or MFAS to validate the data, Enewold says.

 

The service conducted a BAMS preliminary design review with Northrop Grumman in February, and parts are being ordered for the first aircraft as subsystem critical design reviews are executed. The first fuselage is scheduled to go into a jig at Northrop’s Moss Point, Miss., facility next month; final assembly will take place in Palmdale, Calif.

 

Enewold says that since the contract award a need to “beef up” the pedestal that holds the MFAS radar was discovered. Though this shift didn’t impact system weight, they are closely watching it in order to maintain the “effective time on station (ETOS)” requirement of the program. The Navy wants BAMS to achieve an ETOS at 2,000 nm., providing 24/7 coverage 80% of the time.

 

Initial operational capability of three air vehicles is slated for December 2015. The Navy must also control three vehicles aloft at once to achieve this milestone, a requirement driven by the need to have one aircraft on station, one in transit and one returning to base to meet the ETOS demand.

 

 

  RQ-4N BAMS (illustrated) ⓒ Northrop Grumman

 

  Global Hawk Maritime Demonstration ⓒ Northrop Grumman