Innovative Taxiway Design - ACConline.org

Fall 2012
Consulting
A Publication of the Airport Consultants Council
Innovative Taxiway Design
USING MODELING TO
COMPLY WITH THE FAA’S NEW
PROPOSED TAXIWAY DESIGN GROUP
By Fin B. Bonset, M.Sc., Simtra Americas
The Federal Aviation
Administration’s (FAA)
Airport Design Advisory
Circular (AC) 150/5300-13
is considered a “near-holy”
document for anyone involved in airport
development in the United States. Airport
planners and engineers consider it to be the
go-to manual in designing airside facilities.
Over the years, the document has evolved
through frequent amendments and addendums
to account for the ever-changing
airport planning and design process in order
to reference industry trends such as new
aircraft types and concerns for operational
safety. There is a lot of buzz in the industry
about the FAA’s complete re-write of the
AC, which is expected to be released this
fall. So what is in store for airport planners
and designers
The latest and greatest iteration of the document
has the designation AC 150/5300-
13A. The “Alpha” designation at the end is
quite appropriate based on one of its many
definitions: “being the most prominent,
talented, or aggressive item in a group.”
The current changes are quite profound,
prominent, and certainly more aggressive,
when compared to the current edition of
the document.
NEW TAXIWAY DESIGN GROUP
One of the most significant changes in the
new AC pertains to new taxiway design
criteria. A new proposed “Taxiway Design
Group” (TDG) will replace the current,
long-accepted way of doing business under
the trusted Airplane Design Group (ADG).
The main difference is that TDG incorporates
elements related to actual aircraft
movements of a specific taxiing aircraft,
instead of the current ADG wingspan and
tail height requirements which are more
related to safety clearances to objects or
other aircraft. The TDG will be based on
Main Gear Width (MGW) combined with
Cockpit to Main Gear (CMG) distance.
Furthermore, all taxiway fillet design
will now be based on maintaining the
aircraft’s cockpit over the centerline,
which has essentially eliminated the old
judgmental over-steering concept from
See INNOVATIVE on page 16
page 4
SPECIAL FEATURE:
MINIMIZING THE
INSIDER THREAT
WITH AIRPORT
WORKER ID
MANAGEMENT
page 6
CONSULTANT
PERSPECTIVE:
EDUCATING THE
LOCAL AIRPORT
POLICY MAKERS
page 12
PHOTO REVIEW OF
THE ACC SECURITY
CAPABILITIES DAY
AND SUMMER
WORKSHOP SERIES

ACC MEMBERS
And the Winner Is…
INNOVATIVE continued from page 1
AECOM has been awarded an $85 million construction management contract for the
new Midfield Terminal Complex at Abu Dhabi International Airport. AECOM will
work with Hill International as the prime sub-consultant and take on responsibility
for many aspects of the construction of the 7.5-million-square-foot Midfield Terminal
Building as well as the required associated airside and landside infrastructure. The
terminal, which will be able to handle more than 30 million passengers and will have
sufficient piers to accommodate 65 aircraft including the Airbus A380, is scheduled to
open during 2017.
C&S COMPANIES received a platinum 2012 Engineering Excellence Award from the
ITHACA
TOMPKINS REGIONAL AIRPORT sustainable master plan that was featured as a case
study in the Fall 2009 issue of AirportConsulting. C&S was the consultant for the country’s
first FAA-funded master plan that integrates sustainability principles throughout
the planning process. Because this project still had to meet the requirements of the
FAA for master plans, the team had to create a new model for airport master planning
that maintained requirements, while also integrating sustainability elements. One new
aspect on the project was a baseline assessment of 11 sustainability categories. Data
was gathered and analyzed for each category, and areas of weakness and strength were
identified. The results were used to set goals and objectives to guide decisions about
how to meet upcoming facility needs. This project was responsible for the FAA’s initiation
of a sustainability planning pilot program at 10 airports nationwide.
HNTB CORP. was awarded $7 million to complete a series of safety improvements
to one of the south airfield’s runways and a pair of taxiways at Los Angeles
International Airport. The arrangement, approved by the Los Angeles Board of
Airport Commissioners, also calls for making improvements to the eastern cargo apron
of the Century Cargo Complex, according to an LAX report. The Federal Aviation
Administration called for the airfield improvements at LAX so that the airport can meet
a new set of safety standards set to go into effect in 2015.
LANDRUM & BROWN has been selected to partner with the Civil Aviation Management
Institute of China (CAMIC) to provide five years of Executive Management Training
for mid-level airport managers from China. The partnership was announced at a ceremony
officiated by Civil Aviation Authority of China (CAAC) Deputy Administrator
Xia Xinghua and attended by Director General Qin Zhanggao of the CAAC Airport
The three week overseas training will follow a 10-week domestic training curriculum,
and will focus on various aspects of airport planning, air traffic operations and strategic
management issues, including sustainability, security, safety, and customer service
quality. The training will take place twice a year and will involve participation by various
member companies of the ACP, and tours of airport facilities and operations. As
members of the US-China Aviation Cooperation Program (ACP), L&B will also include
other industry experts on key topics of safety, security and IT management to ensure
that the most current methods and technology are represented.
airport design literature. To compensate
for the overall elimination of judgmental
over-steering (which is basically a way to
reduce fillet pavement), the turning radii
for each design group have been decreased
significantly, i.e. the old ADG-VI fillet
radius of 170 feet has been reduced and
changed in designation to “TDG-7” with
only 130-feet of radius. And yes, that
smaller radius works just fine, even for
such critical long wheel-based aircraft as
the Airbus A340 and A380.
However, those seeing the drawings for
the first time may think the new TDG
fillet schematic designs look quite “funny.”
In reality, when testing the new radii with
simulation software, the new taxiway fillet
only does it work from an operational
point of view, but it also saves on the
amount of fillet pavement required by as
much as 5-15 percent, depending on which
TDG is being used. And, as we all know,
less pavement equals less cost.
COST SAVINGS THROUGH
TECHNOLOGY
As noted above, the FAA seems to
have taken a new and positive stance
on the further allowance of pavement
reduction and cost saving beyond its
new TDG concept. But there is another
important aspect to the AC: “The use of
Computer Aided Design (CAD) in lieu
of Table 4-3 through Table 4-8 to model
aircraft movements is acceptable and
may be necessary for intersections with
nonstandard angles.” (Tables 4-3 through
4-8 are all of the new TDG tables with
16 Consulting, Fall 2012

COVER STORY
ACC Weighs in
on New Airport
Design AC
the fillet dimensions and radii). This is
revolutionary. Based on this small literary
excerpt, it appears that the FAA is keeping
up with the times. “Modeling” is the key
word here, which is becoming more and
more prevalent in today’s fast-paced and
graphics-hungry airport design world. Thus,
if an airport operator/representative has
the means to successfully model a taxiway
fillet design based on actual aircraft gear
movements while adhering to new FAA
TDG criteria, it can reduce the area of
pavement to the most optimal amount.
What types of tools are available to
enhance taxiway fillet design CAD-based
simulation software can provide complete
simulation to handle a large variety of
planning and operational aspects, including
accurate fillet design. This software
operates based on the actual movement and
speed of a specific aircraft’s nose gear and
main gear.
So how does it work The designer can
choose a point on the aircraft to follow a
specific curve (“cockpit over the centerline”
can be chosen), limit the aircraft’s nose
gear steering angle (to the FAA’s 50-degree
limit), and have the software follow a line
of any specified radius until a stop-point is
designated. The software then creates an
offset line (in color) from the outer edge
of the actual aircraft main gear tire, which
is based on the FAA (or ICAO) main-gear
clearance requirement of that particular
design group aircraft. Once complete, a
movie can be created from the simulation.
Airports and consultants in other parts of
the world have been using such software
for years in order to save on pavement costs
and have been relying on the critical aircraft
instead of the maximum design group
requirements. In the U.S. however, the
maximum AC 5300-13 ADG requirements
have been promoted, thus resulting in more
pavement than needed. With the new AC,
this is no longer the case. The reduced fillet
requirements of the new Taxiway Design
Group, coupled with the allowable usage
of software, will enable consultants to
provide not only airports, but the FAA and
the airport industry as a whole with cost
savings and operational efficiency while
maintaining all required safety clearances.
In conclusion, the FAA has come up with
a concept that pertains to actual aircraft
movement based taxiway design. With
the involvement of the industry, the FAA
has been open to new concepts which are
more realistic. The new AC, based on
actual aircraft modeling, appears to be a
solid solution for future airport design and
overall system cost savings. As with all new
things, the industry may take some time
to get used to the new standards, but then
again, the tools for implementation already
exist.
ACC was invited by the FAA to provide
comments on the new draft Airport
Design AC 150/5300-13A, “Airport
Design.” ACC members participated
in a workshop sponsored by the FAA
in April to review new concepts and
requirements under the draft AC.
ACC also solicited comments from
members and submitted over 90
pages of suggestions to the FAA
(a copy of the comment letter
can be found on the ACC website
www.ACConline.org).
Some of the major changes provided
in the new Airport Design AC and
discussed in ACC’s comments include
the following:
» The Taxiway Design Group
(TDG) concept
» Better explanation and
examples on Declared
Distances
» New electronic Design Group
Tables
ACC also asked how the new design
standards will be implemented,
particularly for projects that are
currently underway or have already
been designed. ACC will be sponsoring
webinars to inform the industry on
the major changes contained in the
new AC — refer to the ACC website
for more information.
www.ACConline.org
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