Equipment requirements for business and regoinal aircraft:

 - May 5, 2008, 11:16 AM

From now until March 29, 2005, business aircraft operators, including those that fly overseas–even if only occasionally–will be required to have a number of additional, and possibly expensive, avionics and other communications, navigation and surveillance (CNS) equipment. This equipment is intended to provide enhanced CNS capabilities for both operators and ATC. Operators without the required boxes face ATC handling and airspace restrictions, particularly in Europe.

For some older aircraft, the required equipment will be especially costly, both in pricing and downtime. These aircraft will have to undergo modifications to bring them up to the technical level that will permit the equipment to work, and have the installation FAA approved. In the case of some older aircraft, such as the Sabreliner, OEMs have stepped up to the plate to offer upgrade programs. For others, mod shops, such as Duncan Aviation, are obtaining STCs and Form 337 approvals for various aircraft models.

One of the first pieces of equipment whose current requirement is being expanded are radios with 8.33-kHz channel spacing. The traditional 25-kHz channel spacing in the crowded VHF radio band can no longer accommodate the ever-growing demand for new frequencies. To alleviate the shortage of VHF radio frequencies available to ATC, particularly that for the congested upper airspace of Europe, the introduction of 8.33-kHz channel spacing was recommended.

The carriage of 8.33 kHz-channel-spacing-capable radios (a minimum of two per aircraft is required) became mandatory in October 1999 in seven European countries for flights above FL 245. Those countries are Austria, Belgium, France, Germany, Luxembourg, the Netherlands and Switzerland. At the end of next month 8.33-kHz radios will be required for flights above FL 245 for the following 22 additional countries: Bosnia and Herzegovina; Croatia; Czech Republic; Denmark; Estonia; Finland; Hungary; Ireland; Italy; Latvia; Lithuania; Macedonia; Norway; Poland; Portugal; Slovak Republic; Romania; Slovenia; Spain; Sweden; UK; and Yugoslavia.

An analysis of flight-plan data submitted to Eurocontrol’s Central Flow Management Unit indicates that more than 98 percent of the flights in the affected airspace are already 8.33-kHz equipped. “The identification of all aircraft that will need to be equipped with 8.33-kHz radios after October 31 is essential for the safe and timely implementation of 8.33-kHz-channel-spacing operations,” Eurocontrol said. All the major suppliers of panel- and remote-mounted transceivers for business aircraft offer radios with 8.33-kHz spacing ranging in (uninstalled) price from $5,000 to $18,000, depending on additional features.

Meanwhile, operators using European airspace are still waiting for the increased ATC capacity promised as a result of being required to carry 8.33-kHz radios. Some resectorization of airspace has taken place, but don’t expect a lot of capacity expansion until next year–well after the 22 additional countries fully implement the new frequency configuration. Also, Eurocontrol warns that current exemptions to operate without 8.33-kHz radios will not be extended beyond next month and no new exemptions will be granted.


Unlike 8.33-kHz radios, most Part 91 and 135 operators do not yet have TAWS (terrain awareness and warning system) installed, as they are yet to be required on business airplanes built before last March. But the clock is ticking–class-A TAWS units become mandatory on January 1 for newly manufactured European-registered airplanes with mtows of 12,500 lb or more used in commercial operations; and on March 29, 2005, TAWS will become required for U.S.-registered private and commercial turbine airplanes configured with six or more passenger seats.

The European TAWS requirement for business airplanes is officially designated as starting at 5,700 kg, which converts to 12,566 lb. Nevertheless, regulatory officials have steadfastly maintained that the rule is meant to apply to airplanes starting at 12,500 lb mtow, although FAA and JAA airworthiness certification rules define small airplanes as those with mtows of 12,500 lb or less. The bottom line is that some European-registered turboprops, such as the larger King Airs, and some early-model business jets will be covered in the European TAWS requirement starting next January 1. However, helicopters are off the TAWS hook.

TAWS has been required on new-production U.S.-registered turbine airplanes since last March 29. For those in the field, class-B TAWS will be required in all in-service Part 91 turbine-powered airplanes configured (not “type certified,” as originally proposed) with six or more passenger seats and Part 135 turbine airplanes with six to nine seats. Part 135 airplanes with 10 or more passenger seats and all Part 121 airplanes, meanwhile, must be equipped with the more robust class-A TAWS.

The more expensive class-A TAWS offers more features than class-B units. For instance, while both types offer forward-looking terrain avoidance and imminent-terrain impact alerts, class-A units offer five additional modes of ground-proximity warnings and class-B offers just two additional modes. Class-B units do not require a radio altimeter or a display, but must have an approved GPS to provide horizontal position information.

More details on the technical description and regulatory aspects of TAWS (as well as RVSM) are available in a guidebook from Duncan Aviation, the Lincoln, Neb. company that specializes in avionics installations. The 32-page free booklet, called “Straight Talk About TAWS,” describes what TAWS does and how it works, the regulatory requirements, and answers a series of most-asked questions. The booklet is available from Duncan at (800) 228-4277.

Additionally, the FAA has published Advisory Circular 25-23 that provides guidance for designing an approved installation of a TAWS in Part 25 airplanes. A separate AC to provide guidance for TAWS installations in Part 23 airplanes is still under development.

By various estimates, there are some 15,000 corporate airplanes in the field for which the TAWS rule applies. Simple math means that since the rule was adopted in March 2000, about 3,000 systems per year now need to be manufactured, delivered and scheduled for installation. Although there are many installation centers, the most popular ones are filling their reservation books fast, according to industry sources.

Fortunately, the FAA has eased the technical requirements for TAWS installations by foregoing the STC process for class-B equipment. In a recent bulletin to FSDOs, the FAA spelled out the change in policy, which allows thousands of Part 91 and 135 operators affected by the TAWS rule to install the required equipment under the less stringent FAA Form 337 field-approval process–provided that an STC has been approved previously in a “similar installation.” The previous approval does not have to involve the same model or type of aircraft, but should deal with “a comparison of interfaces (sensors, displays and so on) and operational characteristics,” said the FAA. Questions about the bulletin (FSAW 02-03A) may be directed to the FAA at (202) 267-3809.

While the FAA’s policy change eases installation requirements, the TAWS suppliers issue turned murky in May, when Honeywell (builder of the Enhanced Ground Proximity Warning System, also a TAWS unit) filed suit against the other TAWS manufacturers for alleged patent infringement (AIN, August, page 1). In the lawsuit, filed in U.S. District Court for the District of Delaware, Honeywell is asking that Goodrich, Sandel Avionics and Universal Avionics be enjoined from selling their TAWS units and that the company be awarded an unspecified monetary amount. If the suit holds up in court, thousands of operators required to have TAWS installed might find that Honeywell with its EGPWS will become the sole supplier. (See AIN, August, page one for more on the lawsuit and its possible ramifications on supplies and prices.)

Recognizing that some smaller turbine and recip aircraft operators will want to equip with TAWS even though they are not required to do so, the FAA has proposed the addition of a third class of TAWS, and suggests it be known as class C. If adopted, class-C equipment would be intended for voluntary installations on aircraft not covered by the TAWS rule. Makers of TAWS units asked the FAA to add the third classification to allow them to market TAWS products that do not meet the minimum requirements for class-A or -B TAWS units, but still offer some of the safety benefits of TAWS at lower prices. Class-A TAWS pricing starts at about $20,000; class B begins at $12,000.

Another potential supplier of TAWS (not named as a defendant in the Honeywell lawsuit) is Aviation Communications & Surveillance Systems (ACSS), a Phoenix-based division of L-3 Communications and Thales Avionics of Paris. ACSS said it is developing a combined TAWS/TCAS, dubbed T2CAS, that will provide GPS and wind-shear warning options, as well as terrain safety standards required by the TAWS mandate, said the company.

ACSS officials claim that T2CAS will be the only TAWS product to provide avoidance alerts based on actual aircraft performance data rather than based on standard climb rates and an assumption that all critical functions are performing properly. For example, if one engine on an aircraft fails while it is approaching a mountain, T2CAS will factor in the decreased performance while accurately alerting pilots of any necessary avoidance maneuvers.

Meanwhile, Sandel Avionics of Vista, Calif., recently dropped the price of its class-B TAWS to less than $20,000. (See “Avionics Update,” AIN, August, page 86.)

ELTs, AEDs and EMKs

When ground proximity warning systems were initially mandated for the airlines many years ago, it wasn’t the FAA that promulgated the requirement. It was an act of Congress instructing the FAA to enact appropriate rulemaking. History has repeated itself, this time for emergency locator transmitters in corporate jets. An act of Congress, specifically the AIR-21 legislation of 2000, instructed the FAA to issue a rule that would require ELTs in all U.S.-registered jet airplanes involved in non-scheduled operations starting Jan. 1, 2004.

That compliance date is a compromise between the FAA and Congress, the latter of which wanted the compliance date to be January 1 last year. But the agency convinced lawmakers that a later date was needed to give operators time to consider equipping their airplanes with 406-MHz ELTs instead of, or in addition to, 121.5-MHz units.

In 2009, satellite-based monitoring of 121.5-MHz ELTs will terminate in favor of the 406-MHz ELTs. The 406-MHz units are considered more reliable than the older units, and also emit a stronger signal that can be detected almost instantaneously by satellite, the FAA said. At press time, Artex Aircraft Supplies was the only provider AIN could find of 406-MHz ELTs. Operators will have to contact Artex to get pricing information for its 3.6-lb Artex 406-MHz unit. Other providers reported that they plan to have 406-MHz units available by the January 2004 deadline.

Congress took the unusual action of once more treading into the aircraft operational arena to remove business jets from the ELT exemption after a Learjet 35 crashed in IMC on approach to Lebanon (N.H.) Municipal Airport (LEB) in 1996. Although the aircraft was the subject of several intense search missions, it wasn’t found until 1999, and that was an accidental discovery.

In addition to the customary airframe-mounted unit, there’s even a 121.5-MHz ELT you can wear on your wrist–the Breitling Emergency wristwatch. The range of the signal varies, but Breitling said that on flat terrain a search aircraft at 20,000 ft msl could detect the signal up to 100 mi away. The transmitter has a 48-hr power reserve. Retail price of the Emergency watch (which is also a chronometer) is $3,500.

On May 12, 2004, just four months after the compliance deadline for ELTs in corporate jets, some charter operators will face a new equipment requirement for their larger turbine airplanes. By that date, FAA-approved automated external defibrillators (AEDs) and enhanced emergency medical kits (EMKs) must be installed on all Part 135 and 121 aircraft that have a maximum payload capacity of more than 7,500 lb and require at least one flight attendant, which roughly translates to aircraft with at least a capacity for 30 passengers.

While AEDs are not required by the FAA on most business jets, many operators and several OEMs have elected to install the devices. For example, AvBase Aviation, the charter arm of I-X Jet Center at Cleveland-Hopkins International Airport, was one of the first air-taxi firms to equip all its charter airplanes, as well as its headquarters, with AEDs.

Gulfstream last year became the second business jet manufacturer to start including an AED on all new customer aircraft. The installation includes training for Gulfstream crews on the equipment from MedAire of Phoenix. Gulfstream has been offering new customers a one-year subscription to MedAire’s in-flight medical assistance programs since 1989. Boeing was the first OEM to supply an AED and associated MedAire training for business aircraft, specifically for new BBJ customers. AEDs are available from several manufacturers (see box) and all are priced in the $3,000 range.

Larger regional carriers are also included in a new rule that requires airplane manufacturers and operators to change the way airplane fuel tanks are designed, maintained and operated. Calling it “the most comprehensive fuel tank safety initiative ever put forward,” the FAA said the rules are aimed at minimizing the potential for failures that could create ignition sources in fuel tanks on new and existing airplanes.

The rule, adopted last year, affects nearly 7,000 transport airplanes, a few of which are playing business aviation roles as corporate shuttles, with 30 or more seats manufactured by Airbus, Aerospatiale, Boeing, BAE Systems, Bombardier, de Havilland, Fairchild Dornier, Embraer, Fokker, Lockheed, Saab and Shorts. Manufacturers have until the end of this year to conduct the safety reviews and develop required maintenance and inspection programs. Operators, meanwhile, will have until June 6, 2004, to incorporate FAA-approved maintenance and inspection programs. Advisory Circulars 25.981-1B and 25.981-2 provide information and guidance for operators to comply with the new rules.

Squawking on Mode-S

Today’s conventional secondary-surveillance radar (SSR) technologies of ATC have reached their capacity limits, just as the VHF communication frequency spectrum has, at least in Europe. These limits take the form of ATC radar being bombarded with more targets than it can process, radio frequency (RF) pollution, lost targets and identity errors. Mode-A and -C code shortages already exist in some high-density traffic areas in Europe, leading to takeoff delays while a crew waits for a squawk. Hence, since last year, mode-S has been mandatory for all new airplanes operating in European airspace, regardless of country of registration.

Mode-S transponders enable a unique identification of aircraft through the registration number or call sign, removing the risk of confusion due to overlapping signals. This selective interrogation of aircraft identification and other features of mode-S are intended to not only overcome the technical limitations of the current SSR systems, but also allow airspace capacity “to continue to increase in a safe and efficient manner,” according to regulators.

Specific benefits of mode-S, according to regulators, include improved safety by ensuring higher surveillance data integrity; reducing RF interference; increase airspace capacity by overcoming the mode-A/C code shortage; reduce controller workload; and improved efficiency by providing ATC with additional aircraft derived data, “thus increasing ATC’s efficiency in radar separation tasks.” Mode-S transponders also provide interface with TCAS and have air-ground datalink capability.

The requirement for all aircraft using European airspace to be equipped with mode-S transponders will take effect next March 31 for IFR flights. For VFR operations conducted in airspace where SSR transponders are mandated, mode-S will be mandatory starting March 31, 2005. A requirement for mode-S enhanced surveillance capability has been given a target implementation date of Jan. 1, 2005. However, this has yet to be formally approved by Eurocontrol and the JAA.

It’s important to note that the mode-S requirement applies to all aircraft using European airspace. Not all JAA requirements apply to non-JAA registered aircraft. JAA rules apply to all aircraft using European airspace if they deal with equipment in which ATC communications or surveillance is involved, (such as mode-S transponders and 8.33-kHz radios) or in which aircraft interrogate other aircraft (such as TCAS).

In the early 1990s, the FAA adopted a requirement for mode-S transponders on virtually all IFR aircraft, but was forced to put a hold on implementation in mid-1992 when it acknowledged the ATC system was not yet fully prepared for widespread use of mode-S technology. In the FAA’s typical unrealistic optimism, it expected the ATC system to be ready by 1995. It didn’t happen. In fact, by mid-1996 the FAA was forced to admit it hadn’t worked out all the bugs and rescinded the installation requirement. Despite the technological advancement of the ATC system in the last several years, there still remains no requirement for mode-S transponders in U.S. airspace or on U.S.-registered aircraft, except for aircraft in which TCAS II is installed.

Mode-S transponders are available from Garmin International, Honeywell, Rockwell Collins and UPS Technologies at pricing ranging from $5,000 to $33,000. Note that the UPS system is a 4MCU size box.

The Three C’s of RVSM

Perhaps one of the most controversial, complicated and challenging technical requirements for business aircraft operators is obtaining approval to operate in reduced vertical separation minimum airspace (RVSM), which compresses the vertical distance between aircraft tracks from 2,000 ft to 1,000 ft to add six more flight levels between FL 290 and FL 410.

Implementation of RVSM was initiated in October 1998 in the North Atlantic. Since then, the Pacific, Australia, Europe and Northern Canada airspace have incorporated RVSM as well. RVSM airspace is set to be established in the Middle East and parts of Asia next November. And U.S. and southern Canada RVSM are scheduled for implementation in December 2004.

And there’s the rub. General aviation trade groups are incensed over the FAA’s proposal to implement domestic RVSM all at once from FL 290 through FL 410 in December 2004. Published in May, the proposal immediately drew the wrath of AOPA and the Aircraft Electronics Association, both of which said phased introduction of DRVSM is needed to give aircraft operators time to comply. NBAA and the General Aviation Manufacturers Association warned last summer that the proposed start date leaves insufficient time to ensure a smooth transition for business aircraft operators, scores of whom will be required to make costly upgrades to avionics and flight controls.

The associations told former FAA Administrator Jane Garvey, “Having to develop and publish required Service Bulletins and STCs, install the required equipment in more than 6,000 airframes and then have FSDOs verify their certification argues persuasively for a longer lead time.” Additionally, there is “considerable uncertainty” within the FAA’s flight standards office over whether there is sufficient manpower to process the flood of operational approvals DRVSM will produce.

NBAA and GAMA suggested to the FAA that the agency could also “streamline” the transition to DRVSM by changing the requirements to have separate HMU flight testing following each RVSM upgrade of a non-production aircraft. “Manufacturers should be allowed to take credit for HMU test data collected at the time of [equipment] installation.”

Only about 1,400 business jets are RVSM approved out of a total U.S.-registered population of about 7,500. Comments on the proposal were due by August 8. (For more on the controversy surrounding RVSM, see AIN, April, page 82.)

The FAA also ignored business aviation’s concerns over the altitude range for RVSM airspace over the Pacific. The rule, implemented last February, established RVSM in the Pacific FIRs between FL 290 and FL 390. NBAA believed Pacific RVSM altitudes should be consistent with Atlantic RVSM altitudes (FL 290 through FL 410). NBAA president Jack Olcott said, “the FAA dismissed the association’s legitimate safety concerns by implementing a requirement with different parameters in different airspace locales. This rule could have minimized the safety and training concerns within the business aviation community by the standardization of flight levels of RVSM airspace globally.”

Duncan Aviation has prepared a free booklet entitled “Straight Talk About RVSM.” The 30-page document describes how RVSM works, the international regulatory requirements and the scheduled implementation dates, and it answers a series of most-asked questions. Meanwhile, operational information on RVSM airspace in northern Canadian domestic airspace is available from Nav Canada at (613) 562-5678 or at under “Service Projects.”

The FAA will present the second of five DRVSM seminars this month in Orlando, Fla., in conjunction with the 55th annual NBAA Convention. The agenda for the meeting, to be held at the Peabody Hotel on September 8 and 9, will include DRVSM program overview; aircraft and operator approval policies and processes; safety and monitoring considerations; and air traffic services aspects and policies. The remaining three DRVSM seminars will be conducted in the Southwestern, Northwestern, and Central/Great Lakes areas. Another seminar will be held next spring, details of which will be announced. Those planning to attend must register with the FAA. For more information contact Karen Rees by fax at (202) 863-2398.

Collision Avoidance by TCAS II

Traffic alert and collision avoidance systems type II (TCAS II) have been required on U.S.-registered turbine airplanes with 10 or more passenger seats and used in commercial service since January 1996. Since January 2000, all European-registered private and commercial fixed-wing turbine-engine airplanes with mtows exceeding 33,000 lb, or a max passenger configuration of more than 30 seats have been required to carry and operate ACAS II (TCAS II with change 7).

Starting on Jan. 1, 2005, all civil fixed-wing turbine-engine airplanes with mtows of 12,500 lb or a max passenger configuration of more than 19 seats will also be required to carry and operate ACAS II in Europe. This requirement will apply to all airplanes, whether or not they are JAA-certified.

Some business aircraft operators, the NTSB and others have expressed concern over the fact that U.S.-registered cargo airplanes have been exempt from TCAS requirements. But that could change soon. Virtually all cargo aircraft will be required to have TCAS installed by October 31 next year, under a notice of proposed rulemaking (NPRM) issued last November. (It’s likely that date will slip, since the agency has yet to publish a final rule.)

Under the NPRM, cargo turbine airplanes with mtows of more than 33,000 lb operated under FAR Part 121, 125 or 129 would be required to be equipped with TCAS II. Cargo turbine airplanes with mtows of 33,000 lb or less operated under Part 121, 125 or 129 would be required to be equipped with at least TCAS I (a less sophisticated system that doesn’t provide resolution advisories as TCAS II does). Furthermore, all cargo piston airplanes, regardless of weight, conducting operations under part 121 or 125 would be required to be equipped with TCAS I.

Under development is TCAS III, which provides resolution advisories (RA) in the horizontal and vertical plane. TCAS II provides RAs only in the vertical mode. There are no current plans to require installation of TCAS III.

There have been numerous incidents reported in which TCAS alerts have helped prevent either a midair collision or a close call, and there have been no known situations where TCAS has been implicated in a midair or near midair. Safety investigators are now looking into the role, if any, TCAS may have played in the fatal midair on July 1 between a DHL Airways Boeing 757 and a chartered Bashkinian Airlines Tupolev Tu-154 (see AIN, August, page 16.)

There are three ACAS/TCAS II manufacturers–ACSS, Honeywell and Rockwell Collins. Uninstalled prices range from $113,000 to more than $200,000.