[Federal Register Volume 81, Number 247 (Friday, December 23, 2016)]
[Proposed Rules]
[Pages 94277-94281]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-30910]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 91
[Docket No. FAA-2015-2147; Notice No. 15-05]
RIN 2120-AK51
Transponder Requirement for Gliders; Withdrawal
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Advance notice of proposed rulemaking (ANPRM); withdrawal.
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SUMMARY: The FAA is withdrawing a previously published advance notice
of proposed rulemaking that sought public comment from interested
persons involving glider operations in the National Airspace System.
The action responded to recommendations from members of Congress and
the National Transportation Safety Board and was intended to gather
information to determine whether the current glider exception from
transponder equipage and use provides the appropriate level of safety
in the National Airspace System. The FAA is withdrawing that action
because the limited safety benefit gained does not justify the high
cost of equipage.
DATES: This action becomes effective December 23, 2016.
FOR FURTHER INFORMATION CONTACT: For technical questions concerning
this action, contact Patrick J. Moorman, Airspace Regulations Team,
AJV-113, Federal Aviation Administration, 800 Independence Avenue SW.,
Washington, DC 20591; telephone (202) 267-8783; email:
[email protected].
SUPPLEMENTARY INFORMATION:
Background
On August 28, 2006, a Hawker 800XP aircraft \1\ and a Schleicher
ASW27-18 glider were involved in a non-fatal midair collision near
Reno, Nevada. The collision occurred in flight about 42 nautical miles
(NM) south-southeast of the Reno-Tahoe International Airport (RNO), at
an altitude of about 16,000 feet (ft.) above mean sea level (MSL), and
in an area where gliders are excepted from the transponder equipment
requirements in Title 14, section 91.215(b), of the Code of Federal
Regulations (14 CFR).\2\ The glider was equipped with a transponder,
but the transponder was not turned on at the time of the accident.
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\1\ The Hawker 800XP aircraft was equipped with a Traffic Alert
and Collision Avoidance System (TCAS). TCAS is a family of airborne
devices that function independently of the ground-based air traffic
control (ATC) system, and provide collision avoidance protection for
a broad spectrum of aircraft types. All TCAS systems provide some
degree of collision threat alerting, and a traffic display.
\2\ The exceptions to the rule allow aircraft that were
originally certificated without an engine-driven electrical system,
such as balloons and gliders, to be operated in the following areas
without a transponder: within a 30 nautical mile radius (NMR) of the
36 listed airports listed in Appendix D to part 91 (Mode C veil),
provided aircraft remain outside the Class A, B, or C airspace and
are below the ceiling of the airspace designated for the Class B or
C airport, or 10,000 feet MSL, whichever is lower; above 10,000 feet
MSL; and in the airspace from the surface to 10,000 feet MSL within
a 10 NMR of any airport listed in appendix D, excluding the airspace
below 1,200 feet outside of the lateral boundaries of the surface
area of the airspace designated for that airport.
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On March 31, 2008, the National Transportation Safety Board (NTSB)
provided safety recommendations to the FAA resulting from an
investigation of the accident.\3\ The findings of the accident
investigation address the limitations of the see-and-avoid concept in
preventing midair collisions and, more specifically, the benefits of
using transponders in gliders for collision avoidance. The NTSB
recommended that the FAA remove the glider exceptions pertaining to the
transponder equipment and use requirements, finding that ``transponders
are critical to alerting pilots and controllers to the presence of
nearby traffic so that collisions can be avoided.''
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\3\ A-08-10 through 13, Safety Recommendations. National
Transportation Safety Board, Washington, DC 20594, March 31, 2008. A
copy of this letter has been placed in the docket.
www.regulations.gov docket FAA-2005-2147. Note: while NTSB used the
term ``exemption'' the correct term as it relates to this airspace
is ``excepted.''
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On June 16, 2015, the FAA published an Advance Notice of Proposed
Rulemaking (ANPRM) to respond to recommendations from two members of
Congress \4\ and the NTSB. 80 FR 34346. The ANPRM requested comments on
a proposed rulemaking that would require gliders operating in the
National Airspace System (NAS) to be equipped with transponders. The
FAA did not propose specific regulatory changes but rather sought
public comment on the use of transponders in gliders operating within
the excepted areas of Sec. 91.215. The ANPRM also sought input on more
recent alternatives to glider equipage including the use of Traffic
Awareness Beacon System (TABS) \5\ and Automatic Dependent Surveillance
Broadcast (ADS-B) Out equipment.\6\ The FAA asked for comments from the
public and industry to aid in the development of a proposed rule and
the analysis of its economic impact.
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\4\ The FAA received letters from Senator Harry Reid (D-NV) and
Representative Mark E. Amodei (R-NV); Letters are posted to the
docket at www.regulations.gov, docket no. FAA-2015-2147.
\5\ TABS is a surveillance system derived from existing
transponder and ADS-B requirements. It was developed to increase
safety by providing a standard for a low cost surveillance solution
for aircraft excepted from Sec. Sec. 91.215 and 91.225. An aircraft
equipped with TABS is visible to other aircraft equipped with
collision avoidance systems such as Traffic Advisory System (TAS),
Traffic Alert and Collision Avoidance System (TCAS) I, TCAS-II, and
ADS-B In. However, a TABS-equipped aircraft is not displayed to
controllers. The FAA published Technical Standard Order (TSO)-C199,
the standard for TABS, on October 10, 2014.
\6\ ADS-B is a satellite-based surveillance system that uses
Global Positioning System (GPS) technology to determine an
aircraft's location, airspeed, and other data, and broadcasts that
information to a network of ground stations, which relays the data
to air traffic control displays, and to nearby aircraft equipped to
receive the data via ADS-B In.
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Overview of Withdrawal
Based on the information gathered from the ANPRM and a review of
the current operating environment, the FAA finds that it does not have
sufficient basis to move forward with rulemaking at this time. While
the FAA has determined it is not warranted to move forward with a
proposal to remove the glider exception in Sec. 91.215, the FAA will
continue to work with local glider communities to increase safety
awareness. The FAA will also continue to consider surveillance system
alternatives and to work with interested persons to mitigate the risk
of aircraft collision with gliders. Further, the FAA recommends that
all glider aircraft owners equip their gliders with a transponder
meeting regulatory requirements, a rule-compliant ADS-B Out system, or
a TABS device.
Comment Summary
The FAA received 231comments in response to its ANPRM. Of the 231
comments received, approximately 18 organizations and 213 individual or
anonymous commenters responded. Approximately 161 comments were
unfavorable (adverse), 52 comments were favorable, and 18 comments were
[[Page 94278]]
neutral. Of the 18 organizations that commented, 14 responded
unfavorably (adverse), 2 favorably, and 2 were neutral. Three comments
received after the comment period closed were also considered.
The following organizations responded: Soaring Society of America
(SSA), Aircraft Owners and Pilots Association (AOPA), Vintage Sailplane
Association (VSA), Experimental Aircraft Association (EAA), Civil Air
Patrol (CAP), National Transportation Safety Board (NTSB), American
Association for Justice (AAJ), and approximately 11 local soaring clubs
or groups. Individual and anonymous commenters were representative of
all pilot types: glider, general aviation (GA), airline and military,
many commenters holding multiple ratings, with glider and general
aviation pilots representing the majority.
Individual and anonymous commenters in favor of removing the
transponder exception were primarily concerned about safety, some
relaying personal experiences not accompanied by supporting
documentation, such as a near mid-air collision (NMAC) report.\7\
Several commenters recommended the FAA consider alternatives to
transponder equipage, including ADS-B,TABS, or FLARM.\8\
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\7\ An NMAC is an incident associated with the operation of an
aircraft in which a possibility of a collision occurs as a result of
proximity of less than 500 feet to another aircraft, or a report is
received from flightcrew members stating that a collision hazard
existed between two or more aircraft. A report does not necessarily
involve the violation of regulations or error by the air traffic
control system, nor does it necessarily represent an unsafe
condition. The fact that flightcrew members initiate NMAC reports
raises two important issues. First, to some degree the data likely
will be subjective. This necessitates that considerable caution be
exercised when evaluating individual NMAC reports. Second, it is
most likely the number of NMAC reports filed will not represent the
totality of such events.
\8\ FLARM is an electronic system designed to alert pilots of
potential collisions between aircraft. FLARM is approved by the
European Aviation Safety Agency for fixed installation in certified
aircraft. Aircraft equipped with FLARM (including a variant known as
PowerFLARM that can receive transponder and ADS-B signals from other
aircraft) are visible only to other FLARM-equipped aircraft. There
is no FAA TSO for FLARM because FLARM uses proprietary technology
rather than industry consensus standards.
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All comments are available for viewing in the rulemaking docket
(FAA-2015-2147). To view comments, go to http://www.regulations.gov and
insert the docket number.
Discussion of Comments
1. Safety Benefit of Transponders
Of the approximately 161 unfavorable (adverse) comments received,
many addressed the high cost of transponder equipage and the limited
safety benefit by requiring such equipage.
During the ANPRM process, the FAA also reviewed glider midair and
NMAC reports at the local and national level. After further analysis of
safety related statistics, the FAA found that nationally, from August
2005 through August 2015, the Aviation Safety Reporting System (ASRS)
database reflects 1,841 reported NMAC for all airspace areas. Of these
NMACs, 50 involve a glider and another aircraft type, or 2.72% of
reported NMACs over a 10-year period for an average of 5NMACs per year.
In 2008, the last year data was available for all aircraft categories,
statistics show there were 236,519 active aircraft, including 1,914
gliders, or about 0.81% of the active fleet.
Nationally, the removal of the glider exception from Sec. 91.215
would help to prevent those instances where a glider NMAC occurs with
an aircraft equipped with a Traffic Alert and Collision Avoidance
System (TCAS).9 10 However, instances where removal of the
glider exception from Sec. 91.215 help prevent a glider NMAC due to
increased air traffic controller awareness are assumed negligible
overall, because the operating areas for gliders are often in places
with little or no radar coverage. Furthermore, because gliders can
maneuver rapidly, glider flight paths are difficult for the Air Traffic
Control (ATC) automation system to accurately project. Over the 10-year
period reviewed, of the 50 reported NMACs involving a glider and
another aircraft type, 7 involved a glider and part 121 or 135 air
carriers required to have TCAS. Using this analysis, removal of the
glider exception from Sec. 91.215 has the potential to reduce the NMAC
occurrences by about 0.70 occurrences per year, or about 2 NMACs every
3 years (0.38% of all reported NMACs per year over that period).
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\9\ This assumes all gliders are equipped with a transponder.
\10\ TCAS provides two types of advisories, a Traffic Advisory
(TA) and a Resolution Advisory (RA). TCAS can provide both types of
advisories using another aircraft's transponder signal. A TA
provides an aural alert ``TRAFFIC, TRAFFIC'' to the flight crew and
places the other aircraft on a cockpit display showing the other
aircraft's position, altitude and movement relative to the TCAS-
equipped aircraft. TCAS also computes the time to closest point of
approach between the two aircraft. If this drops below a certain
computed threshold, TCAS then provides a RA, which consists of aural
commands and instrument cues to maneuver the aircraft vertically to
avoid the threat.
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Assuming all of these NMACs would occur between gliders and air
carrier aircraft,\11\ this would represent an incremental NMAC hazard
of approximately 3.8 x 10-8/flight hour to the air carrier
aircraft, based on air carrier flight hour data for years 2010-2014
published on the NTSB's Web site. This rate of occurrence is within the
acceptable hazard level guidelines for a Hazardous failure condition
(not greater than the order of 1 x 10-7/flight hour)
according to the FAA System Safety Handbook, Appendix B.\12\
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\11\ Air carrier aircraft are the fleet segment of greatest
safety concern to the FAA for this contemplated rulemaking. These
aircraft are required by regulation to be TCAS-equipped.
\12\ Appendix B of the FAA System Safety Handbook defines a
hazardous failure condition as one that reduces the capability of
the system or the operator ability to cope with adverse conditions
to the extent that there would be: Large reduction in safety margin
or functional capability; Crew physical distress/excessive workload
such that operators cannot be relied upon to perform required tasks
accurately or completely; Serious or fatal injury to small number of
occupants of aircraft (except operators); or Fatal injury to ground
personnel and/or general public.
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Therefore, based on the nationwide rate of occurrence, safety risk
data does not support a rule requiring glider operators to install a
transponder device at this time. Furthermore, the number of gliders
voluntarily equipping with collision avoidance systems has increased
steadily. Per the General Aviation and Part 135 Activity Surveys, the
number of gliders equipped with a transponder device has gone from 14%
in 2006, to 24.3% in 2014, the last year this data was available.\13\
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\13\ Number of active gliders with transponders: 2014 GA Survey,
Avionics Tables, Table AV.6. https://www.faa.gov/data_research/aviation_data_statistics/general_aviation/.
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Locally in the airspace surrounding Reno, Nevada, the NTSB noted
four TCAS Resolution Advisory (RA) events in the 30 days prior to the
accident, each between a glider and a TCAS-equipped transport category
aircraft operated under 14 CFR part 121.\14\ For these RAs to occur,
the glider involved in each RA would have to be flying with an operable
transponder (turned on).
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\14\ A-08-10 through 13, Safety Recommendations. National
Transportation Safety Board, Washington, DC 20594, March 31, 2008. A
copy of this letter is in the docket at www.regulations.gov, docket
no. FAA-2015-2147.
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Although this data supports the value of transponders in avoiding
collisions, since the accident, the FAA and local glider community have
also taken several measures to mitigate the risk of midair collisions
within and around Reno, NV. First, advisory information on the heavy
glider activity unique to the local area was published in official FAA
flight information publications including the Chart Supplement, Special
Notices, and Standard Terminal Arrival Routes (STARs) for Reno/Tahoe
International Airport after the event. Second, on October 29, 2010, a
Letter of Agreement (LOA) was signed between representatives for the
local glider
[[Page 94279]]
community and ATC facilities having control over the airspace. The LOA
establishes an area and procedures for glider operations within
positive controlled airspace in the Reno area. By establishing this
area and these procedures, the LOA enhances airspace awareness and
communication among the Oakland Air Route Traffic Control Center,
Northern California Terminal Radar Approach Control, and the Pacific
Soaring Council. Additionally, the LOA outlines entry and exit
procedures into the operating areas and identifies pilot
responsibilities to increase communication and situational awareness in
the Reno area.\15\
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\15\ The LOA is posted in the docket at www.regulations.gov,
docket no. FAA-2015-2147.
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Finally, the local glider community has undertaken a successful
education campaign to prevent further accidents. According to the SSA,
``Since the 2006 accident, the local glider community that flies near
RNO has undertaken successfully to educate pilots on collision
avoidance and to encourage the voluntary use of either FLARM or
transponders. As a result of these voluntary efforts, the official ASRS
database includes no new incidents with gliders not equipped with
transponders in the RNO or MEV [Minden-Tahoe Airport] areas in
[excepted] airspace since the release some 7 years ago of the NTSB
report on the 2006 incident.'' \16\
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\16\ SSA comment letter posted in the docket at
www.regulations.gov, docket no. FAA-2015-2147.
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The SSA, EAA, and several individual commenters opposing
transponder equipage, noted that the glider involved in the 2006 Reno
accident was equipped with a transponder, but at the time of the
accident, the pilot operated the glider with the transponder turned
off.\17\ The FAA acknowledges that in the 2006 accident, if the glider
transponder were turned on, the Hawker aircraft would have received
TCAS advisories.
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\17\ 14 CFR 91.215(c) states: While in the airspace as specified
in paragraph (b) of this section or in all controlled airspace, each
person operating an aircraft equipped with an operable ATC
transponder maintained in accordance with Sec. 91.413 of this part
shall operate the transponder, including Mode C equipment if
installed, and shall reply on the appropriate code or as assigned by
ATC. This collision occurred at approximately 16,000 feet MSL in
Class E airspace (which extends upward from 14,500 feet MSL to
flight level 180 throughout the National Airspace System).
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2. Estimating Glider Transponder Cost From Removal of Glider Exception
Approximately 138 commenters discussed the cost of requiring
gliders to equip with transponders.\18\ Of those 138 commenters
discussing cost, there were just 20 comments that could be
characterized as in favor of requiring gliders to equip with
transponders to some degree.
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\18\ Most comments addressed the cost of transponder equipage. A
few comments addressed the cost to install other equipment such as
ADS-B, TABS, and FLARM. The FAA sought comment on these technologies
in the ANPRM. These alternatives and others are discussed later in
this notice.
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Three commenters stated that transponders were inexpensive, but as
shown below these commenters underestimated the cost of glider
transponders as ``in the few hundred dollar range'' or ``less than
$2000'' and/or ignored the cost of installation or assumed installation
was easy. They did not address the concern that about half the glider
population does not have an electrical system, which significantly
increases the cost of transponder installation. These commenters were
contradicted by more than 30 commenters who provided specific cost
estimates for glider transponders and installation costs. Another
commenter, in favor of removing the glider exception because he
believed that the safety benefits justified the costs, conceded that
transponders ``are indeed costly.''
The FAA estimates the cost of requiring gliders to equip with
transponders to be about $5,000 per glider and more than $7 million for
the glider fleet. Owing to a lack of reliable data, the glider (and
fleet) cost estimates do not take into account the possible significant
cost of instrument panel modification. There may also be significant
additional cost for older gliders that no longer have manufacturer
support because they may require a FAA Form 337 (Major Repair and
Alteration) approval if there is no prior approval (Supplemental Type
Certificate (STC) or other previously approved installation).
The fleet estimate assumes that (1) all active glider operators
will want to operate in the currently excepted airspace and (2) the 990
inactive gliders (total glider population of 2781--1791 active gliders)
in the fleet will deregister upon rule implementation.\19\ The $7
million fleet figure would be an underestimation to the extent these
two assumptions are incorrect. Details of the estimates of cost per
glider and glider fleet cost are shown in Table 1.
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\19\ Total number of gliders and number of active gliders: 2014
GA Survey, Table 2.1.
Table 1--Glider Transponder Unit Costs
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Item Cost Sources/notes
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Transponder.................... $2,339 Cost based on the Trig
TT21 as it appears to
be the most popular
glider transponder.
Cabling........................ 146 Aircraftspruce.com:
Trig TT21 including
custom harness--$2485.
Antenna........................ 169 Cumulus-Soaring.com:
RAMI AV-74-1 Blade
Style Transponder or
DME Antenna: ``. . .
like the AV-74--but
with longer mounting
studs--which is nice
when trying to mount
it through a glider
fuselage.''
Battery charger................ 25 .......................
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Total Nonrecurring hardware 2,679 .......................
Installation................... 1,300 Average of 32 ANPRM
commenter estimates.
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Total Nonrecurring Cost 3,979 .......................
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Batteries (every 2.5 years).... 600 Battery choice based on
comment by
Philadelphia Glider
Council: ``. . . one
[LiFePO4]18AH or two-
three 9 Ahs generally
sufficient for 10 hrs
of operation.''
CumulusSoaring.com:
Bioenno Power BLF-1209
LiFePo4 Battery 12V,
9AHr $100, charger
$25. Or BLF-1220 20AHr
$205, charger $30.
Duration based on
ANPRM comments.
Biannual inspection............ 800 $200 per inspection.
Based on ANPRM
comments.
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[[Page 94280]]
Total Recurring Costs...... 1,400 .......................
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The nonrecurring and recurring unit costs required to estimate the
cost of a rule change eliminating the glider transponder exception are
shown in Table 1.
The FAA estimates the costs of such a rule change over a ten-year
period for the existing U.S. glider fleet. This estimation is shown in
Table 2.\20\ The cost of a rule change for new production of existing
glider models and new certifications is not estimated owing to a lack
of the necessary forecasts.
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\20\ The estimation takes into account an additional
nonrecurring cost not shown in Table 1 of $400 for gliders without
an electrical system.
Table 2--Ten-Year Cost of Removing Glider Transponder Exception
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Non-recurring PV recurring
Year Item costs Description costs costs @7% \21\
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0.................................. $3,979 Hardware & Installation.... $3,979 ..............
1.................................. .............. ........................... .............. ..............
2.................................. 200 Bi-annual Inspection....... .............. $175
2.5................................ 200 Battery Replacement........ .............. 169
3.................................. .............. ........................... .............. ..............
4.................................. 200 Bi-annual Inspection....... .............. 153
5.................................. 200 Battery Replacement........ .............. 143
6.................................. 200 Bi-annual Inspection....... .............. 133
7.................................. .............. ........................... .............. ..............
7.5................................ 200 Battery Replacement........ .............. 120
8.................................. 200 Bi-annual Inspection....... .............. 116
9.................................. .............. ........................... .............. ..............
10................................. .............. ........................... .............. ..............
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Totals......................... .............. ........................... 3,979 1,009
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\21\ A discount rate of 7 percent is recommended by Office of
Management & Budget, Circular A-94, ``Guidelines and Discount Rates
for Benefit-Cost Analysis of Federal Programs,'' October 29, 1992,
p. 8.
\22\ Number of active gliders with electrical systems gliders:
2014 GA Survey, Avionics Tables, Table AV.1. https://www.faa.gov/data_research/aviation_data_statistics/general_aviation/.
\23\ Number of active gliders with transponders: 2014 GA Survey,
Avionics Tables, Table AV.6. https://www.faa.gov/data_research/aviation_data_statistics/general_aviation/.
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Total number of active gliders 1791 Cost/glider Total cost
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Gliders with electrical systems \22\............................ 699 .............. ..............
Gliders with transponders \23\.................................. 461 .............. ..............
Gliders without electrical systems.............................. 1092 400 436,800
Gliders without transponders.................................... 1330 4,988 6,633,798
Cost of rule removing glider exception...................... .............. .............. 7,070,598
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Note: Due to rounding, details may not add up to totals or multiply to products.
Based on the risk reduction data discussed in the previous section
and the estimated costs of equipage listed in this section, the FAA
finds that the degree of risk reduction that could be expected by
requiring transponder equipage for gliders does not justify the cost of
requiring such equipage.
3. Alternatives to Transponders
Several commenters called for ``low cost'' and ``affordable''
transponders (such as a portable transponder) and ADS-B, TABS, or FLARM
equipment. The NTSB noted the FAA published a final rule on May 28,
2010, that added requirements for ADS-B Out equipage that, if combined
with transponder usage, would result in increased traffic awareness and
collision avoidance. The NTSB also commented in response to this ANPRM
that TABS may be an acceptable alternative as it is detectable by both
TCAS and ADS-B-In equipped aircraft.
Since the 2006 accident, technologies have developed and
alternatives are available that have the potential to mitigate risk,
such as TABS, FLARM, ADS-B, local LOA with ATC facilities, and ongoing
outreach and education. Of the technological solutions identified here,
the ones that offer the best potential to avoid collision with TCAS-
equipped aircraft (besides transponder equipage) are TABS or a rule-
compliant ADS-B Out system, because those systems make the glider
visible to TCAS-equipped aircraft, ATC or both.
The TABS standard provides for a reduction in the transmission rate
and allows for a ``non-aviation grade'' GPS engine, in order to drive
unit cost down while still maintaining an acceptable level of service
to be considered a client in the NAS, where collision avoidance and
ADS-B systems coexist. There are currently no TSO authorization holders
for TABS equipment. However, we are aware that certain manufacturers
currently have TABS systems in development.
Some commenters recommended that the FAA allow use of portable
[[Page 94281]]
transponders, stating they were lower cost than fixed transponder
installations and relatively affordable. While portable transponders
may meet the TSO performance requirements, they are not approved for
use unless they are actually installed in the aircraft. A key reason
for this is placement of the transponder antenna in the aircraft. If
the transponder antenna is not placed correctly, the aircraft may not
be electronically detectable to other aircraft or ATC.
Other commenters recommended that the FAA encourage equipage of
FLARM systems. In this regard, the FAA notes that a variant of FLARM,
known as PowerFLARM, will make a transponder or ADS-B Out equipped
aircraft detectable to the PowerFLARM-equipped aircraft (such as a
glider). However, a glider that is equipped with any version of FLARM
will not be electronically detectable to the other aircraft unless both
aircraft are FLARM equipped. In view of these factors, the FAA
concludes that FLARM systems may provide a safety benefit (particularly
for avoidance of collisions between gliders, and for PowerFLARM
equipped gliders, some benefit for avoidance of collisions with powered
aircraft). However, the FAA does not view FLARM (including PowerFLARM)
as the most effective system to support collision avoidance with
powered aircraft since a FLARM system may not make the glider
detectable to the aircraft that must give way. Transponders, TABS, and
ADS-B Out offer better protection against collisions with powered
aircraft because those systems aid visual acquisition of the glider by
the powered aircraft flightcrew, consistent with right of way
rules.\24\
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\24\ Section 91.113(d)(2) states that ``A glider has the right
of way over powered parachute, weight-shift-aircraft, airplane, or
rotorcraft.''
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The FAA will continue to consider surveillance system alternatives
for gliders for their feasibility and potential to improve safety.
4. Other Comments
Several commenters were in favor of removing the current glider
exception for certain high-density airspace areas. One commenter,
otherwise strongly in favor of removing the glider exception, suggested
an exception for gliders involved in training below 5,000 feet above
ground level (AGL). The FAA has determined not to propose any changes
to the rules for specific airspace areas because the accident and
incident history cited in the NTSB recommendation has occurred
predominantly around one specific airspace area, Reno, NV. The FAA has
determined that the post accident mitigations for the Reno area
discussed previously in this notice mitigate the risk for that specific
airspace.
Another commenter stated, ``the FAA should make clear that
installing a transponder, encoder, antenna, an extra battery or
batteries and possible solar panels are all considered `minor
modifications' which can be signed off by the installing technician
based on his judgment.'' This commenter and several others, in
opposition of the removal of the glider exception, also called for
exceptions for older gliders. The FAA finds that rulemaking is not
necessary at this time for any gliders, but points to current guidance
available to assist in installation and approval of transponder systems
in gliders and sailplanes for operators wishing to voluntarily
equip.\25\
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\25\ Information for Operators (InFO) 09009, Installation and
Approval of Transponder Systems in Gliders/Sailplanes, dated June
10, 2009.
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The AAJ listed glider color, construction materials, and slender
profiles as contributing factors to lack of pilot visibility or radar
detection and further identified Instrument Flight Rule congested areas
as concerns of undeniable risk, especially the parameters of Class B
airspace. These sentiments were largely shared amongst both adverse and
favorable commenters, offering similar solutions or variations thereof.
The FAA has discussed its determination regarding specific airspace
areas above. With regard to the other comments identified here, the
FAA's decision in this notice includes consideration of those comments.
Reason for Withdrawal
After consideration of all comments received, the FAA is
withdrawing Notice No. 15-05. The FAA finds that the high cost of
transponder equipage and the limited safety benefit that is likely to
result from requiring such equipage do not support rulemaking at this
time. Additionally, as discussed above, the FAA has determined that a
proposal to require gliders to equip with ``low-cost'' alternatives to
transponders is not supportable at this time.
NTSB safety recommendations, resulting from the 2006 midair
collision with a glider, indicated that although the glider was
equipped with a transponder, the transponder was turned off. After
further analysis of safety-related statistics over a 10-year period
(August 2005-August 2015) the ASRS database reflects 1841 reported NMAC
for all airspace areas. The FAA found data that indicates that removal
of the glider exception from Sec. 91.215 would have the potential to
reduce the NMAC occurrences by about 0.70 occurrences per year, or
about 2 NMACs every 3 years (0.38% of all reported NMACs per year over
that period).
Conclusion
When further testing, research, and conclusive data is available
that reflect alternative mitigations, a broader, more harmonized
proposal may better serve the public interest. Withdrawal of Notice No.
15-05 does not preclude the FAA from issuing another notice on the
subject matter in the future or committing the agency to any future
course of action. The agency will make any necessary changes to the
regulations through a notice of proposed rulemaking (NPRM) with the
opportunity for public comment.
Although the FAA has determined that a regulatory course of action
is not warranted at this time, the FAA will continue to work with local
glider communities, encourage the voluntary equipage of transponders in
gliders and encourage the use of TABS. The FAA continues to recommend
that all glider aircraft owners equip their gliders with a transponder
meeting the requirements of Sec. 91.215(a), a rule-compliant ADS-B Out
system, or a TABS device. In consideration of the above factors, the
FAA withdraws Notice No. 15-05, published in 80 FR 34346, on June 16,
2015.
Issued under authority provided by 49 U.S.C. 106(f), 44701(a),
and 40103 in Washington, DC, on December 16, 2016.
Gary A. Norek,
Deputy Director, Airspace Services.
[FR Doc. 2016-30910 Filed 12-22-16; 8:45 am]
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