Avionics International had the opportunity to sit co-pilot during a demonstration of the world’s first-ever helicopter radius to fix procedures.

WOODROW BELLAMY III

http://interactive.aviationtoday.com/avionicsmagazine/february-2019/airliner-style-pbn-for-helicopters/

A collaborative use of instrument flight rules procedures and new flight control systems from Hughes Aerospace, working with the FAA, Garmin and AeroNavData, has produced the world’s first use of radius to fix segment coding for helicopter instrument approach and depart procedures.

In December 2018, Hughes Aerospace CEO Chris Baur completed a flight validation of new helicopter IFR procedures using RF for a route consisting of eight different heliports between Morgantown, West Virginia, and Baltimore, Maryland. Baur and the air navigation service provider design team from Hughes developed the low-level helicopter procedure network, culminating during a week-long flight validation activity in the Hughes R66 flight inspection helicopter.

The new procedures use the latest FAA criteria featuring Required Navigation Performance (RNP) 0.3 and RF segment coding. RNP is a performance-based navigation concept using internationally accepted specifications that create precise and determined pathways for fixed and rotary-wing aircraft.

RNP 0.3 is the requirement for an aircraft’s navigation system to be capable of calculating its airborne position within a three-tenths of a nautical mile, and it is the International Civil Aviation Organization’s acceptable level of accuracy for the use of RNP in all phases of helicopter flight. Operators seeking to use RNP 0.3 today are required to add helicopter RNP H124 to their operations specification.

Baur provided an in-the-cockpit flight procedure validation to Avionics International demonstrating the use of RF approaches at one of the hospitals along the new route – Garrett County Memorial Hospital. His company is using a Garmin-equipped Robinson R66 featuring high resolution twin glass displays, and a digital autopilot with stability augmentation and ADB-B In and Out.

One of the central components enabling the new RF approaches is the 66’s Garmin GTN 650H flight management computer. The FMS featured a special navigation database reserved for flight inspection.

“This is historic,” Baur said, as he removed his hands from the controls and watched the GTN 650 autonomously control the R66 from waypoint to waypoint.

It’s the type of flying that Baur, a 40-year veteran helicopter pilot and airline captain, said is common in the commercial airline world but still limited to small pockets of the vertical flight community.

“We want to deliver these type of advanced helicopter Instrument navigation procedures, now common in the air carrier community, to our customers in the vertical flight community,” he said.

“The confluence of RF turns and LPV are used to mitigate heliport obstacles, terrain, noise and airspace issues, while providing safer, lower instrument approach minimums. It’s also wind independent, we noted the wind direction and velocity on each RF leg and recorded bank angles as well. The highest bank angle at any time within this approach was nine degrees. Typically in any helicopter PBN procedure design you want to use less than 20 degrees of bank angle,” he said.

The effectiveness of the RF leg was shown during the first flight demonstration Baur performed in December, which featured cross and tail winds ranging from 20-30 knots. Even in those conditions, the helicopter was able to perform with a cross track error of just 0.00-0.01, or remain within 60.7612 feet.

The procedure was created featuring helicopter RNP 0.3 and radius-to-fix segment coding as a demonstration procedure designed for use by the Maryland State Police.

Baur’s experience flying commercial airliners showed him that through experience the use of RF legs in en route airspace has little-to-no benefit for fixed wing operations. However, at lower altitudes, where helicopters need to fly within defined paths and avoid encroaching on nearby airspace when approaching heliports with terrain and environment obstacles, it can help the helicopter fly the approach more efficiently, especially in IFR conditions.

He sees the use of RF legs in PBN procedures holding massive benefits for reducing fuel and the number of track miles flown, as well as decreasing communication between pilots and controllers attempting to complete point in space helicopter landings.

As the PBN movement spreads into helicopters and the vertical flight community, the benefits in safety, accessibilities and efficiencies are clear, as operators leverage their investments in avionics, particularly in the United States and Europe. This is an example of industry and government collaboration, that has delivered success.

“In these cases, Hughes Aerospace develops a custom procedure, such as the one landing on the helipad at Garrett County Memorial Hospital, and provides this electronically to Garmin,” Bill Stone, senior manager of business development for Garmin’s aviation division said, describing the process of getting the new procedure into the Hughes R66 for flight testing and procedural validation with the FAA.

“Garmin then codes this procedure into a format which can be utilized by the FMS in the GTN 650/750. And finally we provide Hughes with an experimental custom database containing this procedure,” he said.

Garmin first added the use of radius to fix legs as one of the leg types used by the GTN through a 2016 software update. The approach procedures developed by Hughes are the first to take advantage of that update.

The GTN’s ability to autonomously control the collective is a standard capability on the GTN, according to Stone.

“This is a natural capability for our FMS’s such as the one in the GTN 650/750. The GTN has the ability to navigate complex flight plans and all ARINC 424 leg types for all phases of flight including departures, arrivals and approach procedures including the missed approach. Provided the aircraft is equipped with a compatible autopilot, the GTN can provide positive course guidance throughout the entire flight plan,” he said.

Another company that was key to assisting Hughes in getting the new procedure developed and ready for flight testing verification is AeroNavData. The Illinois-based provider of navigation data coding is one of only four companies in the world with a type 1 letter of authorization to provide navigation data IFR procedures in fixed and rotary wing aircraft.

Their main role in the project was to take the raw aeronautical data provided by Baur and the Hughes design team – sourced from the actual flying and airspace waypoint creation of the new approaches – and provide verification and validation. They then sent a file to Garmin containing that source data for the new procedure, which was then converted into a binary machine readable format for the GTN flight management computer.

“ARINC has 23 different path terminators that we use to handle coding for RNAV, RNP or any type of PBN procedure,” Aeronavdata CEO Neal Covington said. “In this case, we were incorporating radius to fix legs into the coding of that raw data, which really just does not exist within helicopter operations today.”

Although the company’s navigation database contains more than 6,000 heliports in the western hemisphere, Covington said the majority of requests for design procedures related to RNP are for fixed wing cockpits.

“This opens up a whole new world for helicopter operators,” Covington said. “Almost all of the requests for coding we get related to the use of RNP has always been for fixed wing aircraft at high altitude, there is a whole world of low altitude operations and approaches that could benefit from this.”

Currently the Maryland State Police procedures are for FAA testing and data collection.

The better navigational and positional accuracy or containment through the use of RNP allows helicopters to operate in instrument meteorological conditions, requiring less airspace when supported by the space-based augmentation systems such as WAAS in the US or EGNOS in Europe. Other benefits include the use of vertical guidance which can have minimums of 250 feet height above surface landing and less than three fourths of a mile of visibility.

Helicopter pilots still continue to fly mostly visual flight rules approaches across emergency medical and law enforcement operations, which can be limited and exposed to icing conditions and reliant upon legacy ground-based navigation aids.

Previously, equipage requirements for the use of RNP routes, approaches and departures were resisted to the airlines or business jets equipped with dual flight management computers, dual inertial reference units and more. Today, helicopter operators can benefit from RNP as well with 0.3 COPTER RNP predicated on SBAS or WAAS.

The upgrades for PBN are also readily available today, as all current generation in-production twin engine helicopters feature navigation system packages that are compliant with international RNP helicopter airworthiness requirements.

There have been efforts to expand the use of PBN in commercial aviation operations through programs such as NextGen in the United States and the Single European Sky ATM Research project in Europe, but the focus in those programs has been fixed wing operations. As an example, the PBN information section of the FAA’s NextGen implementation overview features no mention of helicopters or heliports, with all of the focus centralized around Q and T routes and RNAV/RNP approaches in en route airspace for commercial airliners and business jets.

If an operator is RF equipped, they can operate an LPV approach as any other approach. It is simply required to be listed on the operator’s operation specification.

“The need certainly exists to implement modern navigation procedures for helicopter operators that have been enjoyed by the airline community as well. Now, we just have to keep proving it and show how it can change the way we view the heliport flight environment.”

WOODROW BELLAMY III

Sitting co-pilot during a demonstration of the world’s first-ever helicopter radius-to-fix landing procedures.

A collaborative use of instrument flight rules procedures and new flight control systems from Hughes Aerospace, working with the FAA, Garmin and AeroNavData, has produced the world’s first use of radius to fix segment coding for a helicopter landing procedure.

In December 2018, Hughes Aerospace CEO Chris Baur completed a flight validation of new helicopter IFR procedures using RF for a route consisting of eight different heliports between Morgantown, West Virginia, and Baltimore, Maryland. Baur and the air navigation service provider design navigation procedure design team from Hughes developed the low-level helicopter instrument flight rules procedures after a week-long route verification of the new procedures with the FAA.

The new procedures use the latest FAA criteria featuring Required Navigation Performance (RNP) 0.3 and RF segment coding. RNP is a performance-based navigation concept using internationally accepted specifications that create precise and determined pathways for fixed and rotary-wing aircraft.

RNP 0.3 is the requirement for an aircraft’s navigation system to be capable of calculating its airborne position within a three-tenths of a nautical mile, and it is the International Civil Aviation Organization’s acceptable level of accuracy for the use of RNP in all phases of helicopter flight. Operators seeking to use RNP 0.3 today are required to obtain special authorization from their local civil aviation regulator.

Baur provided an in-the-cockpit flight procedure validation to Avionics International demonstrating the use of RF approaches at one of the hospitals along the new route – Garrett County Memorial Hospital. His company is using a newly-purchased Robinson R44 featuring high resolution twin glass displays, a digital autopilot with stability augmentation and ADB-B In and Out.

One of the central components enabling the new RF approaches is the R44’s Garmin GTN 650H flight management computer. The FMS featured a special navigation database reserved for flight testing.

“This is historic,” Baur said, as he removed his hands from the controls and watched the GTN 650 autonomously control the collective from waypoint to waypoint, as depicted in the approach chart provided below.

As the R44 glided from waypoint to waypoint, a Maryland State Police helicopter’s ADS-B positioning was visible, so Baur opted for the missed approach. By selecting the test procedure his team developed from within the system’s navigation database, the flight management system populated a new set of waypoints, a missed approach using an RF segment arc from HADJI to BRAZY.

It’s the type of flying that Baur, a 30-year commercial airline pilot who is also type rated across multiple helicopter variants and runs an air navigation service provider, said is common in the commercial airline world but still limited to small pockets of commercial helicopter operations.

“I’m really trying to bring the type of predictable approach paths and procedures from the commercial airline world to civilian helicopter operations,” he said.

“You can use RF turns to mitigate heliport obstacles and obtain lower landing minimums at. It’s also wind independent, we noted the wind direction and velocity on each RF leg and recorded bank angles as well. The highest bank angle at any time within this approach was nine degrees. Going forward we will get even more aggressive about how much bank angle we can use. Typically in any helicopter PBN procedure design you want to use less than 20 degrees of bank angle.”

The effectiveness of the RF leg was shown during the first flight demonstration Baur performed in December, which featured cross and tail winds ranging from 20-30 knots. Even in those conditions, the helicopter was able to perform with a cross track error of just 0.00-0.01, or 60.7612 feet.

The procedure was created featuring RNP 0.3 and radius-to-fix segment coding as a demonstration procedure designed for use by the Maryland State Police.

Baur’s experience flying commercial airliners showed him that through experience the use of RF legs in en route airspace has little-to-no benefit for fixed wing operations. However, at lower altitudes, where helicopters need to fly within defined paths and avoid encroaching on nearby airspace when approaching heliports with terrain and environment obstacles, it can help the helicopter fly the approach more efficiently, especially in IFR conditions.

He sees the use of RF legs in PBN procedures holding massive benefits for reducing fuel and the number of track miles flown, as well as decreasing communication between pilots and controllers attempting to complete point in space helicopter landings.

This type of advanced use of RNP though remains limited within global commercial and civilian helicopter operations, the bulk of which exist in North America and Europe. However, there are efforts to continue its expansion, which can only occur with the type of collaborative effort it took to create the new procedures.

“In these cases, Hughes Aerospace develops a custom procedure, such as the one landing on the helipad at Garrett County Memorial Hospital, and provides this electronically to Garmin,” Bill Stone, senior manager of business development for Garmin’s aviation division said, describing the process of getting the new procedure into the Hughes R44 for flight testing and procedural validation with the FAA.

“Garmin then codes this procedure into a format which can be utilized by the FMS in the GTN 650/750. And finally we provide Hughes with an experimental custom database containing this procedure,” he said.

Garmin first added the use of radius to fix legs as one of the leg types used by the GTN through a 2016 software update. The approach procedures developed by Hughes are the first to take advantage of that update.

The GTN’s ability to autonomously control the collective is a standard capability on the GTN, according to Stone.

“This is a natural capability for our FMS’s such as the one in the GTN 650/750. The GTN has the ability to navigate complex flight plans and all ARINC 424 leg types for all phases of flight including departures, arrivals and approach procedures including the missed approach. Provided the aircraft is equipped with a compatible autopilot, the GTN can provide positive course guidance throughout the entire flight plan,” he said.

Another company that was key to assisting Hughes in getting the new procedure developed and ready for flight testing verification is AeroNavData. The Illinois-based provider of navigation data coding is one of only four companies in the world with a type 1 letter of authorization to provide navigation data IFR procedures in fixed and rotary wing aircraft.

Their main role in the project was to take the raw aeronautical data provided by Baur and the Hughes design team – sourced from the actual flying and airspace waypoint creation of the new approaches – and provide verification and validation. They then sent a file to Garmin containing that source data for the new procedure, which was then converted into a binary machine readable format for the GTN flight management computer.

“ARINC has 23 different path terminators that we use to handle coding for RNAV, RNP or any type of PBN procedure,” Aeronavdata CEO Neal Covington said. “In this case, we were incorporating radius to fix legs into the coding of that raw data, which really just does not exist within helicopter operations today.”

Although the company’s navigation database contains more than 6,000 heliports in the western hemisphere, Covington said the majority of requests for design procedures related to RNP are for fixed wing cockpits.

“This opens up a whole new world for helicopter operators,” Covington said. “Almost all of the requests for coding we get related to the use of RNP has always been for fixed wing aircraft at high altitude, there is a whole world of low altitude operations and approaches that could benefit from this.”

Currently the RF approach procedures remain reserved only for flight testing and validation, and all of the heliports along the new route are still reserved to VFR operating conditions.

The better navigational and positional accuracy or containment through the use of RNP allows helicopters to operate in instrument meteorological conditions, requiring less airspace when supported by the space-based augmentation systems such as WAAS in the US or EGNOS in Europe. Other benefits include the use of vertical guidance which can have minimums of 250 feet height above surface landing and less than three fourths of a mile of visibility.

Helicopter pilots still continue to fly mostly visual flight rules approaches across emergency medical and law enforcement operations, which can be limited and exposed to icing conditions and reliant upon legacy ground-based navigation aids. That continues to make any of the aspects of the advanced use of RNP that Hughes demonstrated very limited in the world of helicopter operations.

Equipage requirements for the use of RNP approaches include dual flight management computers and two inertial reference systems. Pilots also need specialized aircrew training and must also demonstrate their ability to do things like use the containment accuracy of WAAS demonstrated at 0.3 RNP.

The upgrades for PBN are also readily available today, as all current generation in-production twin engine helicopters feature navigation system packages that are compliant with international RNP helicopter airworthiness requirements.

There have been efforts to expand the use of PBN in commercial aviation operations through programs such as NextGen in the United States and the Single European Sky ATM Research project in Europe, but the focus in those programs has been fixed wing operations. As an example, the PBN information section of the FAA’s NextGen implementation overview features no mention of helicopters or heliports, with all of the focus centralized around Q and T routes and RNAV/RNP approaches in en route airspace for commercial airliners and business jets.

While the new RF procedure is ready and certifiable today, it remains unpublished and unavailable to suitably equipped helicopters without obtaining special authorization. Moving forward, Hughes is working on the development of three additional helicopter prototype procedures at three new heliports and will be conducting similar demonstration flights in visual meteorological conditions to collect data and identify any obstacles to deploying WAAS–enabled helicopter PBN procedures.

“The need is certainly there for bringing more airliner style procedures to the helicopter PBN world,” Baur said. “Now, we just have to keep proving it and show how it can change the way we view the heliport flight environment.”

http://digitaledition.rotorandwing.com/heliexpo-2019/airliner-style-pbn-for-helicopters/

Air Medical Group Holdings, Inc. has signed a multi-year contract with Hughes Aerospace for COPTER instrument procedures, COPTER RNP routes, procedure maintenance and heliport services. Hughes is providing AMGH and its subsidiaries with the latest in COPTER LPV, LP and LNAV instrument approaches, departures and RNP 0.3 COPTER routes depicted on all digital geo-referenced charting products.

“We are very pleased with the new partnership with Hughes Aerospace. After reviewing all of the options for special use instrument approach procedures and IFR infrastructure development, Hughes was the obvious choice for a number of reasons,” said Mike LaMee, director of operations for AMGH subsidiary Med-Trans Corporation. He added, “The quality of the product, timeliness of development and maintenance support provided by Hughes is unmatched. Also, it truly is a partner, providing unparalleled support and guidance as AMGH continues to expand our IFR infrastructure.”

Chris Baur, president of Hughes said, “We are excited to partner with AMGH and work with its subsidiaries Med-Trans and REACH Air Medical in delivering safe, efficient cutting edge navigation services for flight crews and customers.”

https://www.verticalmag.com/press-releases/hughes-aerospace-amgh-form-strategic-partnership-medical-helicopter-ifr-network

Upcoming developments could pave the way for helicopters to maneuver through even the most obstructive environmental obstacles.

Aviation Week & Space Technology
John Croft
Thu, 2016­12­15 04:00

Israel is showing the aviation industry a new use for noise­ reducing and efficiency­ boosting performance­ based navigation (PBN) procedures: avoiding the rocket’s red glare. More to the point, the precisely defined narrow paths used in required navigation performance (RNP) approaches, a type of PBN procedure, could in theory allow the country to keep all runways at its main international airport, Ben Gurion, and others open during conflicts with its neighbors. The procedures, which are tied to avionics performance rather than ground ­based infrastructure, also could help with community relations by helping to curb runway activity in noise­ sensitive areas in the compact country, where the military controls most of the airspace.

From a military perspective, an advantage of RNP is it can precisely define routes that avoid major cities so the air force, if ever called upon, could use its Iron Dome interceptor system to destroy any incoming rockets and mortars without fear of striking a civilian aircraft.

“In times of conflict, RNP allows the aircraft to not be over major cities, areas Hezbollah and Hamas [would] very much like to target,” says Libby Bahat, head of the aerial infrastructure department for Israel’s Civil Aviation Authority (CAA), of the country’s enemies to the north and west, respectively. “Iron Dome allows the air force to defend those cities and yet allow normal traffic and normal civilian aviation to go into Ben Gurion [Airport].”

The CAA in November declared operational the country’s most precise PBN procedure to date: an RNP authorization required (RNPAR) approach designed by Houston based third party air navigation services provider Hughes Aerospace Corp. The RNPAR to Runway 30 at Ben Gurion, which is near Tel Aviv, a procedure that requires an airline to obtain special approval from regulators, replicates a straight in instrument landing system (ILS) approach with vertical and horizontal precision guidance, but adds the element of curves. Other PBN procedures in use at Ben Gurion are less precise.The Runway 30 RNPAR features “radius to fix” turns that guide an aircraft arriving from the west through a tear drop shaped pattern over the ground to remain clear of military airspace to the south and east of the airport.

The approach has vertical guidance and minimums of 280 ft. above the runway, twice as low as the previously available RNP approach to Runway 30. The RNPAR has other benefits. Chris Baur, president of Hughes Aerospace, says use of the approach, which took two years to develop in large part because of the complex airspace, also reduces track miles and saves fuel. He explains that the RNPAR’s radius to fix design offers better “containment” than legacy RNP procedures, an important element given the strong winds that typically blow eastward from the Mediterranean Sea. Baur says the CAA validated the approach with Hughes in a Boeing 737 simulator in Houston and later at Ben Gurion, using its Cessna Citation Mustang light jet.

Israel began deploying the PBN procedures in 2013 following a renaissance of sorts within the CAA, ignited by the FAA’s downgrade of the country’s safety ranking to Category 2 from Category 1 in 2008. “It was a very good move in the aviation history of Israel,” says Bahat of the changes spurred by the FAA action. Along with updating 80 year old aviation laws that apparently were in place under the British Mandate before the country’s founding in 1948, the CAA tripled its workforce to 120, adding “younger people from the industry that were still flying and knew the business very well.” The FAA restored Israel’s ranking to Category 1 in late 2012.

“One of the steps we did at an early stage was to explore PBN procedures,” notes Bahat, “not only for Ben Gurion, but for the entire route structure for the country.” The CAA published its first PBN procedure in 2013, and one new approach to a runway about every six months thereafter. In an unusual move, Ben Gurion asks aircraft to use Runway 30 and only with a PBN approach between of 11 p.m. and 1 a.m. “We received many requests to allow non PBN airlines to use the airport at that time, and we refused,” says Bahat.

The CAA already has published PBN procedures for its new Ramon International Airport near the southern city of Eilat, a facility ideally suited for the technology, as it is surrounded by mountains with large cities nearby. Ramon is scheduled to open in April 2017, and eventually is expected to have an ILS as well. “It will leave a lot of airspace free for Iron Dome and keep Ramon always open,” says Bahat.

Whether Ben Gurion or other airports will remain open to international airlines during times of strife is unclear. During the most recent conflict, in July 2014, the CAA kept Ben Gurion open, but the FAA banned U.S. aircraft from flying there for 36 hr. due to concerns over rockets and shelling. The European Aviation Safety Agency followed the FAA’s lead and also instituted a short term ban. According to Bahat, during conflicts, the airport has more operational freedom as its controllers can waive noise restrictions on some approaches.

There are no guarantees that RNPAR procedures will make a difference for U.S. carriers, which account for about one third of the traffic at the airport, if similar conflicts occur. However, Bahat says the CAA is “continuing cooperation with the FAA and the U.S. government in a very close, detailed way” and that the U.S. ambassador to Israel, Daniel Shapiro, has been to the airport several times during the past two years and appears to be knowledgeable about traffic flows and the Iron Dome. “He understands the very detailed operational risk analysis that we do and how we can have a very safe civilian aviation, and just a couple miles away have Iron Dome protecting a city. “If I have the FAA confident to keep [allowing] flying to Israel, I will have one big worry off my head,” he adds.

Source URL: http://aviationweek.com/commercialaviation/threatsnoisekeysisraeliperformancebasednavigation

Aviation Daily August 2, 2016  p.4

John Croft

Wikimedia Commons

WASHINGTON—A slate of donated required navigation performance (RNP) procedures for Tacloban City Airport (Daniel Z. Romualdez Airport) in the Philippines may set the stage for further improvements in the island nation’s ground-based aerial infrastructure.

The satellite-based procedures—one GPS approach, one required navigation performance (RNP) arrival and one RNP departure—were donated by Honeywell and partner company Hughes Aerospace, a provider of performance-based navigation procedures worldwide, in the wake of Typhoon Haiyan in late 2013. The storm knocked out the airport’s main terminal and its primary instrument approach aid, a very high frequency omnidirectional range (VOR) station. The RNP procedures are the first to be published in the Philippines.

The new GPS approach to Runway 36 offers a minimum descent altitude as low as 320 ft. compared to 745 ft. for the VOR approach. Aside from the lower minimum altitude, the satellite-based procedure also features fewer track miles and vertical descent guidance through the aircraft’s flight management system.

The RNP arrival procedure connects the non-radar en route environment to the Runway 36 approach, providing for a seamless, continuous descent to the runway. The design, featuring multiple transition points along the circumference of a virtual circle around the airport, is specifically tailored to the local weather.

“The type of design lends itself well to an area with convective activity,” Chris Baur, president and CEO of Hughes Aerospace, said. “If you had weather that was shutting down one quadrant (of the circle), you can slide along the ring to pick up another transition to get to the airport.” Similarly, the RNP departure procedure seamlessly connects the airport to the en route environment for departures.

The new procedures were originally developed to be in place in advance of a papal visit in January 2015, however final approval by the Civil Aviation Authority of the Philippines (CAAP) did not occur until May 2016, with the three procedures going live in late June. Most likely users will include Philippine Airlines and Cebu Pacific, all of which must receive approval from the CAAP.

A Honeywell official based in the Philippines said in addition to a building an RNP approach to Runway 18 at Tacloban, the CAAC will also likely target “four or five” other airports that currently cannot receive airline traffic at night due to a lack of approaches and runway lights.