Embedded Avionics, Military

Coast Guard Common

By by Frank Colucci | July 1, 2013
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Amid all the striking images from Superstorm Sandy last year was action video of sailors hoisted from 30 ft seas by two U.S. Coast Guard MH-60T helicopters about 90 miles off North Carolina. Pilots of the glass-cockpit Jayhawks used the Rockwell Collins Common Avionics Architecture System (CAAS) to navigate to the sinking tall ship HMS Bounty through poor visibility at low altitude. CAAS enabled the aviators to overlay flight plans on weather radar displays and plot return courses with accurate fuel consumption through an integrated Flight Management System (FMS). CAAS, FMS, digital radar, multi-agency radios and an Electro-Optical Sensor System (ESS) are now integrated on the 35 operational MH-60T Medium Range Recovery (MRR) helicopters at air stations around the United States. Upcoming CAAS Block II software will ultimately make all 42 Coast Guard Jayhawks compatible with satellite-based Required Navigation Performance/Area Navigation (RNP/RNAV) in civil airspace. The Coast Guard wants the same capabilities on 102 smaller MH-65E Multi-Mission Cutter Helicopters (MCH) and should fly the first Dolphin with CAAS in 2014.

The MH-65E is due to achieve initial operational capability in 2017. The 9,500 lb MCH and 22,000 lb MRR remain in Coast Guard plans to 2027 or beyond. Both helicopters go through conversion and sustainment programs in Discrete Segments at the Coast Guard Aviation Logistics Center (ALC) in Elizabeth City, N.C. Jayhawk Segment 1 turned HH-60Js into MH-60 Tangos with digital cockpits and modern radios. Dolphin Segment 6 will upgrade MH-65Ds to Echoes with glass cockpits and digital weather radars. In both aircraft, CAAS enhances situational awareness and mitigates cockpit workload by integrating primary flight symbology, digital maps, sensor imagery, engine and systems data, and communication/navigation management on color displays.

Interchangeable Multifunction Displays (MFD), Control Display Units (CDU) and other CAAS Line Replaceable Units (LRU) promise the Coast Guard enhanced fleet readiness. According to MH-60T deputy project manager Lt. Cmdr. Patrick Bacher, “Generally the concept is to keep the same hardware and the same software to the maximum possible on the two airframes.” While Jayhawks and Dolphins rarely mix at the same Coast Guard Air Stations, “Logistically, they’ll have one big pool of CDUs in the system, and their logistics support team managers can divvy those out to the air stations.”

In addition, CAAS gives the Coast Guard benefit of hardware and software evolving for the Army MH-47G and MH-60M Special Operations Aircraft, Army CH-47F cargo Chinook, Marine VH-60N Presidential helicopter, and Canadian Forces CH-147F Medium-to-Heavy Lift Helicopter. (CAAS-Light (CAASL) is still planned for the Army Special Operations A/MH-6M Little Bird.)

The MH-47G took CAAS to war in 2007, and the bigger CH-47F fleet uses the same core hardware and software. CH-47F Product Manager Lt. Col. Michael Hauenstein at the Army Program Executive Office, Aviation in Huntsville, Ala., explains CAAS technology transfer between services. “First, within Rockwell Collins, there is a multi-platform group that looks over reported software issues and planned changes. Second, there is an Army-led CAAS users group that meets on a periodic basis which allows the various services to brief each other on current activities and plans. Third, there have been projects, such as the development of an RNP/RNAV capability in CAAS, where the other services have shared development costs up front.” The Army owns Government Purpose Rights to most CAAS software, but other services with their own development contracts need not go through the Army.

Existing CAAS MFDs, CDUs, Power Switching Modules and Video Processing Modules all use 500 MHz 750-series processors. Software expected this fall will accommodate 1.26 GHz 7448-series processors. New LRUs should be delivered with the faster processor and memory upgrades in 2014. According to Hauenstein, “The payoff with this is that we gain growth room and improve system efficiency.”

The processor updates will assure the Coast Guard aircraft a 50 percent growth margin. “We try and come back to that each time we do a refresh,” said Rockwell Collins CAAS account manager Jim Perkins. “With all the added functionality rolling into the system, that’s taking up additional processing and memory.”

Significantly, CAAS implementation on the MH-65E starts with the MH-60T Operational Flight Program (OFP). “There is a lot of software re-use, but how the information is presented to the aircrew is customized to the MH-65E mission needs,” says Rockwell Collins principal program manager Robert Koelling. “They both have all the same software applications. Where there is a difference in the software, it’s because of the different platform types.”

MRR Modernized

Sikorsky Aircraft in Stratford, Conn., delivered 42 HH-60Js to the Coast Guard from 1990 to 1996 with analog flight instruments, Teledyne tactical displays, Mil-Std 1553B databuses, and analog Bendix RDR-1300C weather radars. The hard-flown Jayhawk later acquired an unreliable FLIR rarely installed and operated only by the cabin crew chief. Aging airframes, obsolescent avionics and a new Airborne Use of Force (AUF) mission after 9/11 launched Jayhawk modernization under the Coast Guard-wide Deepwater initiative.

MH-60T Discrete Segment One with new cockpits, new wiring and structural repairs achieved initial operational capability on Oct. 1, 2009. CAAS gives the MH-60T five smart, redundant, 6-inch by 8-inch active matrix LCDs that array flight and systems symbology, maps and sensor imagery in any combination. Coast Guard pilots typically keep primary flight displays on the two outboard screens and use inboard “working” displays for maps, radar and ESS pictures. The center screen can swap Engine Instrument Caution Advisory System (EICAS) text for maps or sensor imagery. Bacher was a Jayhawk instructor at the Coast Guard Aviation Training Center in Mobile, Ala., and notes, “We were careful in Mobile teaching not to dictate how the cockpit will be set up other than to say, ‘The primary flight display goes on the outboard.’”

Coast Guard CAAS hardware is nearly identical to that in Army helicopters, but an MH-60T cockpit working group teamed with Navy VH-60N engineers to develop a Coast Guard flight data presentation. Rather than the split-screen format used by Special Operations aviators to mix pilotage cues with maps, the Coast Guard opted for full-page flight displays. Coast Guard CAAS also shows expanding square and other automated search patterns. While the legacy Jayhawk had only basic altitude-hold autopilot functions, the MH-60T introduced a three-axis flight director that can fly search patterns hands-off. The Tango pilot can pick a geographic point for an automated approach but still works the collective in a rescue hover. EFW Inc., in Fort Worth, Texas, provides the head-up display on AUF aircraft that shows the pilot basic flight and heading information.

Coast Guard Bravo Zero standards demand helicopters launch within 30 minutes of a distress call, and the MH-60T cockpit was designed for pilots to program their navigation computer on-the-fly with intuitive keystrokes through center console CDUs. The cabin crewchief has a third CDU to access radios, the Harris digital map, and the ESS. Mission plans can also be written on the ground using the Coast Guard Mission Planning System (CGMPS) based on the FalconView mapping application developed by the Georgia Tech Research Institute. Separate Aircraft Weapons and Electronics software puts CGMPS plans on a circuit card for the aircraft data loader. Flight plans can also be downloaded to the MH-60T by radio.

To communicate with various law enforcement agencies, the upgraded MH-60T communications suite supplements dual Rockwell Collins ARC-220 HF and ARC-2l0 UHF/VHF military radios with twin RT-5000 civil-band radios from Cobham Aerospace Communications in Prescott, Ariz. The Rockwell Collins communications/navigation suite on the MH-60T also includes modern VOR/ILS, TACAN, ADF and DF navigation aids, and the integrated Traffic Collision Avoidance System (TCAS).

Legacy Jayhawks sometimes wore oversized FLIR gimbals that prevented roll-on landings, but the MH-60T Electro-Optical Sensor System (ESS) from FLIR Systems in Portland, Ore., packs infrared and low-light and color TV sensors in a permanent 9-inch diameter gimbal. Operated from cockpit or cabin, the ESS fuses thermal and image-intensified views to penetrate atmospheric conditions. “It gives you a much greater capability to reach out and identify things,” said Bacher. The small ball also integrates a multi-mode laser illuminator. “If we were doing fisheries patrol and you spotted a target that might be fishing near a closed fishing area, you can use that laser rangefinder not only for bearing and distance but to populate a lat-long [plot].”

MH-60T Discrete Segment Two included the ESS and a Helicopter Integrated Data Storage System (HIDSS) to record ESS video and feeds from the hoist and cabin cameras of the Helicopter Audio-Visual System (HAVS) on a removable memory module. HIDSS replays data or images from any source on cockpit displays and provided video of the Bounty rescue.

The analog weather radar of the legacy Jayhawk gave way on the MH-60T to a digital Honeywell Primus 700A radar with beacon detection and sea clutter reduction functions to provide some search capability. Discrete Segment 3 plans for a dedicated surface search radar have been deferred, as have the C4ISR upgrades in Discrete Segment 4. The MH-60T already gives Coast Guard crews some text-messaging capability and can send automated position reports to other aircraft and ground stations.

Introducing a skeptical Cape Cod Jayhawk pilot to the MH-60T in early 2010, Bacher demonstrated the capabilities of the modernized MRR on a medical evacuation call. Coast Guard Sector Boston relayed the call from the fishing vessel Sammy Jo 70 miles east of Gloucester, Mass. “The DF picked up their signal long before the regular radios, and it was dead-on.” The helicopter crew keyed a round trip flight plan into the FMS enroute and used radar to find the target. “That was correlated to the DF430. We started picking up a blip on that.”

Bacher continues, “We got the FLIR system working, and, sure enough, we could see them on our screens before we spotted them with the naked eye. As we were approaching the boat you still do a visual recon we had such a clear, crisp picture of this fishing boat, we already had an idea what would be the best spot to lower our rescue swimmer down.” The modernized Jayhawk made the pickup and arrived at Massachusetts General Hospital with fuel within 20 lb of FMS prediction.

E-City will continue MH-60T conversions into next year to give the Coast Guard a full fleet of 42 MRR helicopters. (The Navy has transferred five SH-60F airframes to the Coast Guard to offset Jayhawk attrition.) Starting this summer, Tangos going through Programmed Depot Maintenance (PDM) will receive more fleet upgrades including the Honeywell Aircraft Diagnostic Vibration Management System (ADVMS) and GE T700-GE-401C engines with Triumph Enhanced Digital Engine Control Units (EDECU).

The Coast Guard is meanwhile moving ahead with a CAAS Block II upgrade to be installed in the field. “We did an Operational Analysis [OA] of the original software, and there were improvements that we felt could be made based on the OA findings,” says Bacher. Block II Phase I includes RNP/RNAV capability with a go-round button for a missed RNP approach. “We’re doing it so we meet FAA NextGen requirements and can be certified for RNP navigation within the National Airspace System.” Phase II integrates user-identified Improvements recommended by MH-60T operational testers and fleet users, “Some have to do with cockpit layout, some with functionality in the menus on the CDU how we interface with the system.” The CAAS Block II schedule for the Jayhawk is being formulated.

MCH Modifications

American Eurocopter delivered the first of 96 HH-65A Short Range Recovery (SRR) helicopters with Rockwell Collins avionics to the Coast Guard in 1984. Follow-on orders ultimately give the Coast Guard 102 Dolphins, now becoming more powerful MH-65D Multi-mission Cutter Helicopters (MCH) with digital flight directors, ESS gimbals, and other avionics improvements. The next MCH modernization segment integrates a digital Automatic Flight Control System, digital weather radar and commercial CNS/ATM compatibility in an all-new CAAS cockpit. “What we’re doing now is integrating everything together, so the crew can look at everything together on the display the engine interface, the navigation functionality, and so forth,” says Perkins. “Where they once had to look at multiple dials in the cockpit, now they can see it all at once.”

Despite engine, transmission and tail rotor upgrades, the MCH remains weight- and volume-sensitive. The MH-65E CAAS consequently has only four MFDs, plus dual CDUs and a data transfer and storage unit. The original Dolphin flight director box disappears for a software-based solution. Unlike the bigger MRR, the MH-65E will have no cabin CDU for the crewchief.

CAAS in the MH-65E will build on the ESS, HIDSS and RNP/RNAV integrations already done for the MH-60T. Users will identify mission-specific differences in the OFP, and the Dolphin EICAS will be tailored to different engines and equipment. “Some of the underlying software is used, but some of the Human-Machine Interface software that displays the data will be different,” says Koelling. The Data Concentrator Units which interface CAAS with the air vehicle also have some differences. “When you get input from a sensor on an engine, it’s different from that on another helicopter.”

Rockwell Collins ARC-210 VHF/UHF and ARC-220 HF radios will be standard on the MH-65E, including a DVP-200 digital voice privacy processor. Rockwell Collins ARN-153 TACAN, ARN-147 VOR/ILS, and a maritime search and rescue beacon Direction Finder are integrated on the MH-65E, along with a Honeywell GPS/INS.

CAAS design decisions, test plans and aircraft weight calculations for the MH-65E remain at an early stage, but Rockwell Collins has production hardware and developmental software running in an MH-65E Systems Integration Laboratory (SIL) at Cedar Rapids, Iowa, like that used for the MH-60T. Subsystems will be tested first within software partitions and then within the complete OFP. SIL-tested CAAS hardware and software then goes to the Coast Guard for installation and developmental flight test.

CAAS Block II software will give the MH-60T RNP/RNAV capability for the National Airspace System.Photo courtesyThe five-screen CAAS in the MH-60T provides a Pilot Vehicle Interface with Coast Guard symbology and functionalityA MH-65D Dolphin from Guard Guard Air Station in Savannah, Ga., conducts hoist training. The modernization gave Dolphins a digital flight director to replace 30-year old equipment. Reflecting the weight and space constraints of the Dolphin, the MH-65E CAAS cockpit will have only four Multi-Function Displays and two Control Display Units to access flight symbology, maps, systems information and sensor imagery.Photo courtesy U.S. Coast GuardPhoto courtesy U.S. Coast GuardPhoto courtesy Rockwell CollinsThe Coast Guard Aviation Logistics Center converted HH-60J Jayhawks into MH-60Ts with the Common Avionics Architecture System, Electro-Optical Sensors System and other avionics refinements.Photo courtesy U.S. Coast Guard

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