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AOPA urges OMB to tell FAA to revise DRVSM ruleAOPA urges OMB to tell FAA to revise DRVSM rule

Mr. Joshua Bolten
Office of Management and Budget
725 17th Street
Washington, DC 20503

RE: Domestic Reduced Vertical Separation Final Rule

Dear Mr. Bolten:

The Aircraft Owners and Pilots Association (AOPA), representing the interests of over 400,000 aircraft owners and pilots nationwide, opposes the implementation strategy outlined in the Federal Aviation Administration's (FAA) Domestic Reduced Vertical Separation Minima (DRVSM) Notice of Proposed Rulemaking. As proposed, DRVSM would reduce the vertical separation minima applied to aircraft operating between Flight Level (FL) 290 and FL410 from 2,000 to 1,000 feet over the United States by December 2004. This means that even if the federal government takes quick action and publishes a final rule by September 2003, the industry and the FAA will have a mere 13 months to complete the equipment installation and certification of over 15,000 turbine-powered aircraft.

AOPA does not believe that the FAA can meet the certification demand that its proposed implementation schedule creates. Therefore, AOPA favors a phased implementation strategy (FL350-FL390 by December 2004) as agreed to by industry and the FAA in early 2001, and an extension of the full implementation date to at least December 2006. Doing so will allow the FAA and operators the time needed to comply with the requirements of RVSM airspace.

The aggressive implementation schedule outlined in this rulemaking action will likely result in economic and operational hardships for many within the aviation community. AOPA recognizes that the federal government and airlines will realize system-wide advantages through the utilization of DRVSM, in the form of fuel and time savings and increased system capacity. Unfortunately, the benefits to non-airline, turbine-powered aircraft are not nearly as significant and do not offset the cost of equipage. However, the penalty for not equipping is significant for these operators because RVSM is exclusionary airspace, meaning nonequipped aircraft would not be able to fly at those altitudes. It is important to note that in some instances, the cost to become RVSM compliant would exceed the market value of the airframe. The FAA neglected to conduct an adequate economic review and in the process failed to accurately account for the proposed regulation's substantial adverse economic impact on small businesses. Also, by the FAA's own admission, they may not have the ability to certify all of the aircraft that currently operate in the FL290 stratum and above within the 13-month timeframe.

AOPA also opposes the FAA's withdrawal of the allowance for use of a single RVSM-compliant altimeter for Part 91 turbopropeller aircraft as proposed in the Domestic RVSM Supplemental NPRM, FAA-2002-12261. Instead, the FAA will require these operators to install and certify two RVSM-compliant altimeters, citing a desire to align the rule with international civil aviation regulations as the rationale behind the change.

While the percentage of turboprop aircraft currently operating in the flight levels (FL) 290-410 is not statistically large, domestic RVSM requirements should not be dictated by Canadian, Mexican, or other international civil aviation authorities or standards. Most U.S.-based turboprops are used for domestic travel, not international, and it is AOPA's position that operators should retain the ability to decide how their aircraft will be equipped, not the federal government. Furthermore, Part 91 turboprop operators who desire to take advantage of the benefits of utilizing FL290-410 within the domestic United States should not be penalized by rulemaking that mandates equipage according to international standards.

Implementation schedule

Many of AOPA's concerns are centered on the time and cost needed to equip and certify existing airframes, as well as the FAA's ability to meet the proposed implementation schedule.

  • With the final rule's anticipated publication date of September 2003, owners will have less than a year and a half to bring their aircraft into compliance.
  • The general aviation aircraft fleet is far less homogeneous than the air carrier community, which complicates the issues of service bulletin development and publication and aircraft installations. Manufacturer service bulletins are written to address production aircraft in their original configuration, but most general aviation turbine-powered aircraft are modified to meet customer's requirements. This means, manufacturers (and shops) not only have to address a large variety of airframe types, but also variations in configuration. Also, the associated training of FAA field office personnel becomes increasingly difficult to reconcile in a short timeframe.
  • The systemic limitations involved in RVSM certification are considerable. Currently, there are only two FAA-approved engineering firms capable of performing the required airframe and avionics upgrades. These two companies can only complete an average of two airframes a month, taking little of the burden off of the FAA. According to industry officials, the FAA currently handles a maximum of 3,000 field approvals per year. Therefore, even if the FAA conducted only DRVSM field approvals for the next year (which is impractical), it would still leave thousands of airframes noncompliant.
  • There is also a question of whether or not the components needed to make the necessary modifications will be available for all impacted airframes. There simply aren't enough certified avionics and equipment manufacturers to meet the artificial demand created by the proposed rule.

Economic issues

  • Those owners/operators unable to meet the proposed deadline will suffer significant economic hardships resulting from the need to operate in a lower altitude stratum.
  • The flexibility of their aircraft will also be compromised due to reduced range or load-carrying capacity at lower altitudes. The "on-top" provision of this rule is an imperfect solution at best, as it ignores the operational limitations of many aircraft types.


  • Although the DRVSM altitude stratum is at the upper operating limits of many turbopropeller-driven aircraft, it still remains an important safety option for their pilots, particularly when avoiding weather. The rule fails to address the tactical allowance of operations by non-RVSM-compliant aircraft. In many regions where en route congestion is limited, this could be accomplished with limited air traffic impact.


  • AOPA remains concerned that this rule was issued without the support of several key industry participants. When you consider that in early 2001, the FAA had achieved industry-wide consensus to a plan calling for phased implementation, the question of process becomes that much more significant.

AOPA does not dispute the long-term capacity-enhancing potential of DRVSM. The addition of six flight levels offers increased flexibility to the National Airspace System (NAS). However, any advantages gained in the en route environment will not be fully realized until systemic "choke-point" issues in the terminal environment are resolved. The infrastructure necessary to do this is addressed in the FAA's Operational Evolutionary Plan (OEP), of which DRVSM is a component. Many of these OEP initiatives so critical to improving capacity in the NAS, such as expanding the number of runways throughout the country, are long-term solutions. As a result, the ability to leverage the full potential of DRVSM in the short term is questionable, thus AOPA questions the need for full implementation by the end of 2004.

In short, AOPA is mindful of the need to take full advantage of all available capacity-enhancing tools. However, the FAA must consider all airspace users when implementing new programs or strategies.

Because of DRVSM's importance to the user community, it is incumbent upon the FAA to do everything within its power to ensure its benefits are realized with a minimal impact. As a result, AOPA recommends that the FAA pursue a phased implementation strategy and extend the deadline for total compliance to at least December 2006.


Melissa Bailey
Vice President
Regulatory Affairs

August 22, 2003

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