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Tuesday, April 1, 2003

RVSM: Coming Soon to U.S. Airspace

Jim McKenna, Managing Editor

Reduced vertical separation minimums are a fact of flying in most of the world. U.S. airspace is next, but compliance costs are making operators think twice.

Talk to FAA officials, manufacturer representatives, maintenance executives, even opponents of the change among operators, and they will tell you that in less than two years, aircraft flying at higher altitudes will be doing so at reduced vertical separation minimums over and around the U.S.

You wouldn’t know it yet from the rather small line-up of customers at maintenance shops offering RVSM upgrades that the FAA will require of turbine-powered aircraft before letting them fly at altitudes of 29,000 feet or higher after the middle of January 2005.

From outfits with lone Learjets flying charters to those with scores of regional jets in airline service, operators are refusing to schedule aircraft for RVSM upgrades. Not the least of their reasons are the upgrade cost and doubts that the FAA will to stick to its schedule.

That creates dilemmas for the small number of maintenance companies and manufacturers that have partnered to spend $500,000 or more on developing supplemental type certificates to make selected aircraft RVSM-compliant.

Manufacturers have developed RVSM upgrade packages for most of their aircraft; their investments can be recouped in part through sales of compliant new aircraft. But the teams that developed packages as alternatives to the OEMs, or for aircraft not supported by them, are left wrestling with this puzzle: How do you avoid ticking off long-time customers, but still sell your product at a fair price for a market in which most of the upgrades will have to be done within 21 months?

That puzzle’s pieces may be forced together this June, when the FAA plans to issue final domestic RVSM rules.

"A lot of people think the jury’s still out on this, but it’s not," said Wayne Hunsdorfer, director of corporate avionics and maintenance sales at St. Louis, Missouri-based Midcoast Aviation, which with Sabreliner has developed an RVSM upgrade for the Sabreliner 65 and is working on one for the Sabreliner 80.

Why implement RVSM?

There are several reasons why RVSM will come to U.S. skies. A 30-year-old concept, RVSM in the last six years has been adopted in Europe, northern Canada, Australia, and over much of the Atlantic and all of the Pacific. In those regions, it has reduced congestion and flight delays and increased fuel efficiency. By decreasing vertical separation at FL290 and higher to 1,000 feet, RVSM creates six new flight levels between there and FL410.

The FAA estimates domestic RVSM will save operators $360 million in fuel and efficiency gains in its first year, with savings totaling $5 billion by 2019. That is based on the assumption that 90 percent of affected aircraft will comply with RVSM standards by the 2005 deadline. Which brings us to the real reason domestic RVSM will happen: the big airlines want it.

Wracked with financial losses that will only worsen as the prospect of war in Iraq drives up the price of fuel, airlines want relief. Furthermore, the congestion that put U.S. commercial aviation on the brink of gridlock was alleviated only by the slump in air travel that followed the September 11 terrorist attacks. Little has been done to fix the fundamental problems of crowded airways and packed terminal areas that will resurrect gridlock as air travel revives.

Look at the comments filed in response to the FAA’s May 2002 NPRM outlining domestic RVSM plans. Corporate, general aviation, and regional airline operators and the trade associations that represent them filed pages of objections, critiquing the FAA’s cost-benefits analyses and projections of benefits.

Big airlines like American Airlines and United Airlines (and a key supplier, Boeing) filed just a paragraph or two that basically said, in the words of United’s representative, "we concur with the contents of the proposed rule." (One change they suggested was shifting implementation from December 2004 to January 20, 2005 to coincide with the scheduled update of aeronautical charts. The FAA has made that shift.)

The airlines’ aircraft spend more time flying at FL290 or higher than those of any other operators. They want the benefits of domestic RVSM. They need the benefits of domestic RVSM. Barring a lawsuit, most industry folks seem to agree, they will get those benefits come January 2005.

"The airlines are driving this train," said Dan Derby, senior vice president of operations at Atlantic Aero.

Options abound

That Greensboro, North Carolina designated alteration station in January completed its first RVSM certification of a Cessna Citation 550. Atlantic Aero has a license to use Phoenix, Arizona-based Garrett Aviation Services’s RVSM STC for Citation 500s, 501s, 550s, and 560s. The package uses two Innovative Solutions & Support digital altimeters (or air data display units) with altitude alerting functions, a temperature probe for true airspeed computation, a two-inch standby altimeter for use when panel space is limited, and a backlit circuit breaker panel. The STC covers both single and dual flight director-equipped aircraft.

Atlantic Aero also has teamed with West Star Aviation of Grand Junction, Colorado on an RVSM package for the Learjet 35. West Star aims to gain STCs for Learet 30-series aircraft with the FC-200 autopilot by June. It is teamed with Honeywell on the effort, which is using that company’s avionics, Rosemount static probes, and an Aerosonics standby altimeter.

To fly in RVSM airspace, an aircraft must have two independent altimetry systems, one automatic altitude control system, one altitude alert system, and a Mode C transponder. Altimetry must be accurate to within 80 feet. The altitude control system must be able to acquire and maintain altitude within 65 feet of the selected altitude (or within 130 feet if the type was certificated before 1997). The altitude alert system must warn pilots of a deviation within 300 feet of the selected altitude (or within 200 feet if the type was certificated after 1996).

The aircraft also must be equipped with a traffic alert and collision avoidance system with Version 7.0 software, or a later version.

But compliance goes well beyond equipment. An operator won’t be able to fly in domestic RVSM airspace without a letter of authorization from the FAA. That means demonstrating to your local Flight Standards District Office that you have procedures for conducting RVSM operations and keeping the aircraft compliant, and that your pilots and mechanics are trained in those procedures.

"Operators are really being asked to go on a mini-Part 135 program," said Dave Pleskac. "You have to have a minimum equipment list for altimetry. You have to have the training and the operations manual. For Part 91 operators that have heard horror stories about the switch to Part 135, this will be intimidating."

Pleskac sells RVSM and other avionics retrofits for Duncan Aviation, which has or is working on RVSM STCs for a variety of aircraft, including the Astra, Falcon 10, Gulfstream II, IIB, and III, JetStar II and 731, and Westwind I and II.

Unlike most new equipment requirements, RVSM has significant continuing airworthiness aspects. The altimetry must be checked annually instead of biennially for non-RVSM systems. RVSM systems will have to be recertified after maintenance and the same will have to be done for the aircraft when it is repainted or critical sections of the fuselage are dinged or worked on. And the feds will be watching. Part of the RVSM protocol is for air traffic officials to police aircraft for compliance. The U.S., Canada, and Mexico have set up the North American Approvals Registry and Monitoring Organization at the FAA Technical Center in Atlantic City, New Jersey to be the RVSM traffic cop.

"This is a long-term mandate," said Tim Roberts, Honeywell’s manager of retrofits and new programs. "Operators have to understand that."

Test and inspection requirements are new and specific. While current FAR 91-11 requirements call just for testing of altitude measurement, requirements for RVSM aircraft will test both that and airspeed measurement. That work can be sensitive. "Cross-bleed will be involved in all the testing," Lew Wingate, director of test equipment sales and marketing for Miami, Florida-based Barfield, said. "The valves tend to be very sensitive. Having a fan blowing will cause them to oscillate."

Testing will require air data test sets that meet RVSM tolerances, which for many will mean new test sets.

Tack on to those challenges the price of RVSM packages (anywhere from $110,000 to more than $200,000), and the operators’ reluctance to schedule the work becomes understandable.

They want more analysis from numbers crunchers that it makes sense to invest in work that can equal or exceed 30 percent of their aircraft’s value. They want to know whether the return on that investment is so far out in the future that it would make more sense to eat the higher fuel and engine maintenance costs of staying below Flight Level 290.

Most of all, they want proof the FAA will follow through on domestic RVSM plans. The agency has a history of proposing complex, costly technological mandates, only to drop them after heavy investment by industry. The microwave landing system is a good example. No one in aviation can afford to be left holding an empty money bag if the FAA changes its mind this time.

"We have no immediate plans of having it done," Tim Haase, director of flight operations for West Bend Air, said of an RVSM upgrade for the West Bend, Wisconsin-based Part 135 charter operator’s Learjet 35. With a second 12-year inspection coming due, the need for paint and interior work, and other deadlines in the next two years (such as that for installation of a terrain awareness and warning system), the price tag on RVSM is daunting. A key question? "OK, if I don’t do it and fly below 290," Haase said, "what’s that going to cost?"

Regional airlines are in a similar fix. With short stage lengths and proportionally greater times spent being slowed and maneuvered for sequencing into terminal airspace, their flights won’t benefit like those of the big airlines.

Dulles, Virginia-based Atlantic Coast Airlines is having Bombardier deliver its new Canadair Regional Jets fitted for RVSM operations, said Sean McCourt, who handles flight technology and air traffic issues for the carrier. But the carrier hasn’t yet decided to proceed with retrofitting existing aircraft. A critical factor is that, as part of Atlantic Coast’s agreement to operate as a United Express feeder, United Airlines pays its fuel. "Once the fuel bill becomes a factor for us," McCourt said, "we’ll retrofit."

Developing an RVSM package is a big investment. Most aircraft are covered by group certifications, which apply if an aircraft’s structure, altimetry system, and avionics comply with production standards. These aircraft don’t have to have a pricier and more difficult "non-group" STC. But the STC applicant has to analyze aircraft in his proposed group, and flight test at least five to establish the range of static system error for the prescribed flight envelopes. Flight tests must include one of the oldest and one of the newest aircraft from the serial-number range that the group proposes to cover. Establishing the group’s characteristics and what is needed to make it compliant can be a bear.

When Midcoast Aviation pursued an STC for the Hawker 700, it discovered a major problem. Static port placement during production had been far from standard. Positions varied by 18 inches or more from one aircraft to the next.

The tight tolerances of RVSM require the type or STC holder to identify and fix anything that can disturb air flow (and potentially throw off altimetry) near the static ports. RVSM packages for most aircraft can use relatively standard solutions to that problem. Not so for the Hawker 700. Midcoast and its teammates had to plan for tightening overall system tolerances and develop static error curves to cover the variations. With those curves and other work, Midcoast’s Hunsdorfer said, "we’re going to do subgroups of the original STC that will give us more accurate static corrections and cover almost all of the aircraft." An added benefit of the additional work? Elimination of a 0.72 Mach RVSM airspeed limit on the aircraft.

So far, the pursuers of RVSM packages have been somewhat like the farmer in the movie "Field of Dreams," who dug up a cornfield to build a baseball diamond, assured by a mysterious voice, "If you build it, they will come." Purveyors of the packages are confident customers will come. Many expect customers will line up once the FAA issues final rules in June. But some say customers may just come too late. "RVSM is closing in on the world," Mike Anderson, Garrett Aviation’s director of avionics, said. "This is shortly going to become an issue of selling slots and ending up with some very disappointed people who can’t get their airplanes in. If they wait until this time next year, it’s going to become a panic."

A New World for Paint Shops

RVSM places new burdens on operators and the shops that paint their aircraft.

"RVSM has already changed the way aircraft are painted," said Garrett Aviation’s Mike Anderson. Operators and shops must ensure that repairs and new paint don’t alter airflow

near static ports. Adding a stripe can be costly if it creates a minute ridge that renders an aircraft non-compliant.

"Before we start an airplane, we develop a specialized process manual" to address RVSM issues, said Kirk Wood, paint manager for Elliott Aviation, which in February opened a new paint facility in Moline, Illinois.

Typically, a skin-mapping kit will have to accompany an RVSM aircraft going into a paint shop for use in verifying compliance after the paint is dry.

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