Aviation Week & Space Technology
01/30/2006
With the EP-3 aging fast, Boeing says the 737 offers a larger, more reliable joint-service replacement
Mixed Signals
Boeing is polishing the design of an EP-3-replacement signals intelligence aircraft for use by the U.S. Navy and possibly for the export market.
Moreover, the airframe builder believes the new airplane (a derivative of the P-8A multimission maritime aircraft) could appeal across service lines, perhaps to the U.S. Air Force, which some Pentagon critics contend is not focusing on keeping its lead in state-of-the-art intelligence, surveillance and reconnaissance (ISR) systems. For example, two budget-cutting victims are expected to be the E-10 multi-sensor command and control aircraft--with its revolutionary MP-RTIP radar--and the Joint Unmanned Combat Aircraft System, which was to play a key role in electronic attack.
Boeing's announcement is also likely to trigger other companies to propose offerings. Raytheon has designed and built Britain's Astor ground surveillance aircraft from Bombardier's Global Express. Their investment could be transferred to a sigint version of the aircraft. Also, Northrop Grumman designed versions of the General Dynamics Gulfstream for an Israeli sigint aircraft and the initial competition for the Aerial Common Sensor (ACS).
The 737-derivative sigint aircraft is being presented in response to the death of the Army/Navy ACS contract, a product of Lockheed Martin. Several Pentagon and aerospace industry officials say they believe the answer to disparate service requirements is a common sigint and communications system that can be adapted to a wide range of manned and unmanned aircraft.
Boeing planners object, however, saying a common sensor package will push military users back to a single aircraft. They also tout a worldwide support system for 5,400 commercial 737s that would help keep down the military's inventories and maintenance costs.
"You put together a common architecture, communications suite and sensor packages and you're going to drive yourself toward a common air vehicle, otherwise you're going to pay developmental costs three times and add three types . . . to the inventory," says Tim Norgart, director of Boeing's P-8A business development. [In reality] we're seeing a neck-down of types. Today's budgets are going to drive [the Pentagon] back to joint solutions."
Forward of that is the EO/IR sensor. Boeing's intial concept is for a 14-person mission crew, but the aircraft's size allows for expansion to 25 workstations without crowding
While Boeing's concept targets the Navy, it is not being pitched narrowly as a tactical system like the EP-3. The aircraft's capability could be expanded to rival those of the Air Force's RC-135 Rivet Joint. The company's planners also believe there is an international market for perhaps a couple of dozen of these medium-size signals intelligence aircraft.
So far, however, "the Air Force has not been very proactive in taking the leadership role it could claim in advancing the state-of-the-art for ISR," says a senior intelligence specialist. "Austere budgets make the common theme very popular, but it's been tried several times before and there are huge issues once you try to define common.
"But [the core problem] is not about the technology," he says. "Where we need to see change is in the areas of roles and missions. National [intelligence] organizations need to embrace the services as partners rather than subordinates--or worse, unqualified rubes that only interfere with the national [agencies'] prowess. There also needs to be theater-level implementation of orchestrated instead of scheduled ISR coverage as well as training and documentation on how to employ these remarkable new tools."
While the large-scale, inter-service, inter-agency battles play out, Boeing wants to position itself with a new system that can be tailored to varied needs.
Playing off the basic P-8A Multimission Maritime Aircraft (MMA) (a 737-800 with a longer 737-900 wing), Boeing officials say they will already have a hot production line, an existing contractor logistics support system leveraged off the commercial line, a proven open electronic architecture and common crew workstations that can be adapted to virtually any surveillance task. MMA is to make its first flight in 2009 and have its first operational unit in 2013. Production could then pick up with the sigint aircraft in time to meet the end of the EP-3's flying life.
To ensure the viability of the current EP-3 fleet, the Navy will expand the service-life extension program by around seven aircraft. Each P-3 and EP-3 is being inspected to determine whether it needs the structural enhancement kit through 2011. Under the Joint Airborne Sigint Architecture Modernization Common Configuration Program, electronic obsolescence problems are being addressed as well. The sensor suite is being upgraded to make sure it remains operationally useful through 2017, a Navy official says. Around that time, the remaining EP-3 is expected to reach the end of its service life.
The only significant change to the sigint version of the MMA design will be the addition of a small canoe under the present site of the aft weapons bay to house a series of rotating sigint antennas under a single protective dome. But there is no structural strengthening of the aircraft required because it was already done when the weapons bays for MMA were put in, say Boeing officials.
Israel made similar modifications to a Boeing 737 and employed it as the centerpiece of an operation that tracked and detained the Karine A, a vessel carrying 50 tons of weapons reportedly bound for Palestinian militias in 2002.
Perhaps most intriguing, the large size of the aircraft will offer better antenna separation and longer electronic baselines (nose to tail, tail to wingtip, wingtip to nose). That means the aircraft would be capable of producing more accurate locations and ranges of enemy electronic emitters. A long baseline also means the ability to gather much lower-frequency signals that smaller tactical aircraft use for battlefield sigint. Advanced data links, including satellite communications, would ensure network-centric capabilities for rapid targeting.

Boeing envisions a 737-800-based signals-intelligence aircraft with rows of antennas top and bottom, including an array of spinners in an under-fuselage canoeCredit: BOEING
"We would use the 1.9 million lines of code and the basic open architecture of MMA and then bring in the sigint packages on top of that," Norgart says. "Each sensor package has software code associated with it that runs [on the basic architecture] like an application. We have demonstrated that capability--to roll on a different radar and an additional sensor without writing any more lines of code and without even shutting the system down." Any operator can sit down at any workstation and "tell the system what data you want to see and everything works through the core architecture," he says.
In planning for the new sigint aircraft, Boeing officials are setting the system up for the next-generation capability upgrades to the EP-3. It adds more automation, databases and integration to electronic intelligence-gathering.
While not part of Boeing's presentation, various aerospace and defense industry planners are looking at the advantages of equipping the sigint aircraft with an active electronically scanned array (AESA) radar, network-centric collaborative targeting (NCCT) and Suter Program products. Roughly, that means an aircraft so equipped could precisely locate and identify enemy emitters with NCCT, electronically jam signals with the AESA and invade communications networks with packages of algorithms for intelligence-gathering. In fact, adding AESA is considered a key upgrade to making the aircraft a sigint platform.
Boeing's partners so far are Smiths for flight deck systems; Northrop Grumman for electro-optical and infrared sensors, electronic surveillance measures, data links and self-protection system; and Raytheon for its mechanically scanned APS 137 multi-mode radar and some unspecified sigint systems.
The initial sigint aircraft's design increases the mission crew to 14 positions, well beyond the five for an MMA. However, Boeing officials said that if requirements demand, they can increase the mission crew capacity to 24-25 positions without crowding.
To carry the sigint equipment, designers would take out the MMA's sonobuoy system, anti-submarine warfare rotary launchers and seal the aft weapons bay to hold additional antennas and electronic equipment. Added to the payload would be more communications and the ability to move large files of data faster and with more agility.
The MMA is designed to carry 12,000 lb. of ordnance, a payload that can be rededicated to additional electronics. Moreover, the sigint aircraft will have four positions for wing pylons that could carry variants of the miniature air-launched decoy missile that can be fitted with electronic emitters as a standoff jamming device. Also in the works are disposable unmanned aircraft that can be launched from manned aircraft to get very close to a foe. In particular, the Pentagon is interested in low-power, wireless communications networks favored by insurgents for command and control and triggering improvised explosive devices.
So far, two 180-kva. generators on the engines and a 90-kva. auxiliary power unit provide electrical power. The airframe is designed to operate from 200-41,000 ft.A new Pentagon study, that Boeing officials say will last at least six months and maybe a year, is expected to reassess all the ISR requirements.