Improving safety in EMS and other rotary-wing flight ops
Avionics and training with possible new rules from FAA and NTSB will enhance safety and reduce CFIT.
Simultaneous non-interfering approaches will require both WAAS and RNP approvals, reinforcing the shift toward performance-based navigation (PBN).
FAA's Aviation Safety 2009 Business Plan includes adding RNP/RNAV arrivals and departures to and from airports conducting simultaneous fixed-wing operations.
Termed "simultaneous noninterfering (SNI) ops for RNP /RNAV helicopter routes," the initiative will develop operational guidance, oversight and coordination of efforts within government and industry to incorporate these routes for more efficient traffic flow.
Implementation of these routes will depend on successful transition to the Wide Area Augmentation System (WAAS). For fixed-wing GA operators, 3D approach construction using WAAS data from satellites and approved GPS receivers is already in place.
Existing and additional sites will incorporate an expanded World Geodetic System (WGS) 84, and North American Datum (NAD) 83 database, further enhancing these simultaneous arrival and departure sequences.
WGS 84 and NAD 83 data are obtained from satellite imagery provider Geo_Eye. Earlier space imagery provided roughly 10 to 12-meter resolution for ground-based objects, but with the Feb 23, 2009 entry into service of GeoEye-1, resolution has been increased to under 1 meter.
Such data provides exceptionally accurate visual-mapping criteria for FAA-approved RNP routes and arrivals/departures. A GeoEye-2 satellite is under construction and will further enhance the initiatives of FAA and other regulatory agencies for hyperaccurate terrain depiction.
Corporate SMS and maintenance support
Nearly 20% of the accidents recorded in the past 2 decades listed improper maintenance procedures as contributing factors. Interestingly, record-keeping was found to be inadequate in another 20% of investigated accidents-and that figure could be higher, given the limited oversight of Part 91 operations.
While lagging significantly behind the fixed-wing community with regard to SMS implementation, the rotorcraft world-especially small to medium-size operators-is adopting the concept.
In an increasingly litigious world, detailed record-keeping is vital-and SMS implementation (as recommended by FAA under AC 120-92) will enhance flight department compliance.
One much misunderstood regulation, for both technicians and pilots, is FAR 91.407: "Operation after maintenance." If any significant changes have been made that would affect flight characteristics, a properly rated pilot must fly the aircraft and "make an operational check of the maintenance performed or alteration made" and make an appropriate entry into the aircraft log.
Determining the proper log entry is both subjective and vague. Your local FSDO can help with appropriate wording and provide technical assistance if doubt exists. Likewise, that consultation can provide valuable benefits if issues arise later.
Underwriting (insurance) agencies have determined that a significant portion of these functional check flights did not specifically address the work that was done to the aircraft.
Such oversight or neglect could have serious consequences should the aircraft later be involved in an incident or accident, and exposure exists for both technician and pilot.
Night vision goggles
The spillover of NVG technology from the military to the civilian world has been hugely popular and effective. NVGs simply amplify ambient light, which is present even in darkness.
Their limitations include restricted field of vision (about 38-42 degrees from center) and monochromatic displays (in shades of green).
Current technology limits NVG use to helmet-mounted optics, but the future looks promising for wider fields of view. The US Air Force is experimenting with a 95 degrees field, using four 16-mm tubes (as opposed to 2 standard 18 mm) that include thermal imaging. These may become standard for law enforcement as well as HEMS and civilian use.
Part 2: Hardware: Avionics and alerts-moving toward a glass cockpit
Improved displays for a demanding environment
Chelton Flight Logic, Garmin, Honeywell, Sagem and Universal have all produced primary flight displays (PFDs) capable of displaying terrain and obstruction hazards appropriate for rotorcraft.
Many are already certified on multiple platforms. High-end multiengine ships, like the AgustaWestland AW139 medium twin, incorporate Honeywell's Primus Epic suite-nearly identical to the Gulfstream G550 cockpit-but many smaller aircraft benefit from additional safety tools provided by avionics OEMs.
In fact, the fastest growing market segment in rotorcraft avionics is single-turbine models, where synthetic vision systems (SVS) are becoming more prevalent. FAA and NTSB see terrain awareness and CFIT avoidance as the primary hot topics for rotorcraft.
Special emphasis on HEMS operators may require additional legislation and the recent spate of accidents has raised public awareness and concern. The operators themselves would certainly like to reduce the alarming trend, yet their environment is harsh and unforgiving.
FAA has issued a recommendation for implementing night-vision goggle (NVG) use, and many operators are incorporating them for all night flying with successful results. The agency requires an approved curriculum for training and use, whether under Part 91 or Part 135.