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                                                                      EXHIBIT 99

                                  RISK FACTORS

     From time to time the Company has made, and may in the future make,
forward-looking statements, based on its then-current expectations, including
statements made in Securities and Exchange Commission filings, in press releases
and oral statements.  These forward-looking statements are made pursuant to the
safe harbor provisions of the Private Securities Litigation Reform Act of 1995.
All forward-looking statements involve risks and uncertainties, and actual
results could differ materially from those expressed or implied in the forward-
looking statements for a variety of reasons.  These reasons include, but are not
limited to, factors outlined below.  The Company does not undertake to update or
revise its forward-looking statements publicly even if experience or future
changes make it clear that any projected results expressed or implied therein
will not be realized.

     Limited Operations; History of Net Losses.  The Company has a limited
operating history.  It commenced commercial operations in November 1996 as a
provider of wireless broadband capacity to communications providers on a
wholesale "carriers'-carrier" basis.  In March 1998, ART adopted a new business
strategy of providing wireless broadband data services to business customers
without fiber connectivity.  The Company has generated only nominal revenues
from operations to date, has generated operating and net losses since its
inception and expects to generate significant operating and net losses for at
least the next several years.  The Company had 1997 net losses of $61.7 million
in 1997 and an accumulated deficit of $95.8 million at the end of 1997.

     In light of the Company's brief operating history and change of strategy,
there is limited data about the Company upon which to evaluate its future
performance.  There can be no assurance that the Company will develop a
successful business or achieve or sustain profitability in the future.  The
Company's ability to provide commercial service on a widespread basis and to
generate positive operating cash flow will depend on its ability to, among other
things, acquire adequate access rights for its network, deploy and commercialize
its network, attract and retain experienced and talented personnel, raise
adequate additional capital when required, attract and retain an adequate
customer base and establish strategic business relationships.

     Significant Capital Requirements; Need for Additional Financing.
Significant additional capital will be required to finance the Company's
completion of its network roll-out and operations over the next five years.  The
Company currently estimates that it will require in excess of $1 billion over
the next five years for capital expenditures, working capital and funding
operating losses.  An increase in the rate at which ART deploys its network
would require the Company to raise additional capital at earlier dates.  ART's
actual capital requirements also will be affected, possibly materially, by
various factors including the cost and amount of equipment acquired, customer
acceptance and demand and the prices charged for services, completion and
technological change.  Failure to access capital in the future could have a
material adverse effect on the Company, its ability to implement its business
plan, and its financial condition and results of operations.

     There can be no assurance that the Company will be able to obtain any
financing when required, or, if such financing is available, that the Company
will be able to obtain it on acceptable terms.  In the event that the Company
fails to obtain additional financing when required, such failure could result in
the modification, delay or abandonment of some or all of the Company's business
plan. Any such modification, delay or abandonment is likely to have a material
adverse effect on the Company.

     Risks Related to Strategy.  The Company is pursuing a strategy to become
the leading provider of broadband data services to business customers without
fiber connectivity.  The Company has limited experience in providing these
services, and there can be no assurance that it will successfully implement its
strategy.  The Company has limited experience in deploying, operating and
maintaining a broadband data network.  There can be no assurance that the
Company will effectively deploy, operate or maintain such facilities.  Further,
there can be no assurance that the broadband data network deployed by the
Company will provide the expected functionality. Furthermore, the Company's
strategy is subject to risks relating to the negotiation and implementation of
necessary 
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strategic business relationships with Lucent and other third parties, the
development of value-added products and services, the ability of Lucent and the
Company to design, provision and deploy the Company's network on schedule, the
recruitment of experienced and talented personnel in a timely manner, the
Company's ability to attract and retain customers, and the Company's ability to
manage the rapid implementation of its plan in multiple markets. In addition,
the Company is subject to the risk or unforseen problems inherent in being a new
entrant in a rapidly evolving industry.

     There is significant risk relating to the market's acceptance of the
Company's broadband data-focused wireless services.  The Company and other
providers have only recently begun to market fixed wireless services, and the
Company believes it is currently the only fixed wireless broadband provider
focusing on providing data services rather than voice telephony.  The provision
of such services represents an emerging sector of the telecommunications
industry, and the demand for such services is uncertain.  Demand may be
adversely affected by various factors including historical perceptions of the
unreliability of previous wireless technologies, concerns about the security of
transmissions over wireless networks, the lack of market history of operational
fixed wireless services and the possible desire of customers to acquire
telecommunications services from a single provider.  The Company anticipates
that a substantial investment in sales and marketing will be required to reach
its target customers and to create demand for the Company's wireless broadband
date services.  There can be no assurance that a substantial market will develop
for fixed wireless broadband data services, that sufficient customers will be
willing to purchase such services, or, if such market were to develop, that the
Company will be able to attract and maintain a sufficient revenue-generating
customer base, generate sufficient cash flow to service its indebtedness, or
operate profitably.

     Furthermore, acceptance of the Company's services may be affected by
various factors beyond the Company's control, including the availability and
pricing of alternative broadband and narrowband data services, general and local
economic conditions, changes in products and technology, and the potential
impact of government regulation on the Company's services.  The extent of the
potential demand for the Company's broadband wireless data services cannot be
estimated with certainty.  Insufficient acceptance of the Company's services due
to one or more of these factors, or from other factors, would have a negative
impact on the Company's results of operations and its financial condition.

     Substantial Leverage; Ability to Service Indebtedness.  The Company is
highly leveraged.  It will be further leveraged upon the consummation of the
anticipated Lucent Financing (see "--Reliance on Lucent; Lucent Agreement) and
upon the incurrence of additional indebtedness by the Company.  The Company
expects to incur substantial additional debt to finance its business plan.
Accordingly, (i) a substantial portion of the Company's cash flow from
operations will be required to pay interest with respect to its outstanding 14%
Senior Notes due 2007 (the "Senior Notes") commencing in August 2000, with
respect to the anticipated Lucent Financing commencing in June 2002 and with
respect to any additional indebtedness incurred by the Company, (ii) the
Company's flexibility may be limited in responding to changes in the industry
and economic conditions generally; (iii) the failure to comply with the numerous
financial and other restrictive covenants of such debt may result in an event of
default, which, if not cured or waived, could have a material adverse effect on
the Company; (iv) the ability of the Company to satisfy its obligations pursuant
to such indebtedness is dependent upon its future performance which, in turn, is
subject to management, financial, business and other factors affecting the
business and operations of the Company; (v) the Company's ability to obtain any
necessary financing in the future may be limited; (vi) the Company may be more
highly leveraged than many of its competitors, which may put it at a competitive
disadvantage; and (vii) the Company's leverage may make it more vulnerable in
the event of an economic downturn.  The Company's  ability to make principal and
interest payments on its indebtedness, will be dependent upon, among other
things, the Company's future operating performance and anticipated cash flow and
its ability to obtain additional debt or equity financing on acceptable terms,
which are themselves dependent on a number of factors, many of which are out of
the Company's control.  These factors include prevailing economic, financial,
competitive and regulatory conditions and other factors affecting the Company's
business and operations including the ability of the Company to implement its
network on a timely and cost effective basis.  There can be no assurance that
these factors will not 

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have a material adverse effect on the Company or that the Company will be able
to generate sufficient cash flow to meet required interest and principal
payments associated with its indebtedness. If the Company is unable to generate
sufficient cash flow to meet its debt obligations, the Company may be required
to renegotiate the payment terms or to refinance all or a portion of its
indebtedness, to sell assets or to obtain additional financing. There is no
assurance that the Company would be able to do so. Any failure to meet required
interest and principal payments would materially and adversely affect the
Company's business and results of operations.

     Reliance on Lucent; Lucent Agreements.  The Company and Lucent have entered
into an interim purchase agreement (the "Lucent Purchase Agreement") under which
Lucent will provide a nationwide integrated network and will deploy its
personnel to deploy and maintain ART's network.  Pursuant to the Lucent
Agreements, the Company has engaged Lucent to design, engineer, equip, install,
construct, test and service the Company's nationwide network.  Any failure or
inability by Lucent to perform these functions could cause delays or additional
costs in providing services to customers and building out the Company's network
in specific markets.  Any such failure could materially and adversely affect the
Company's business and results of operations.

     The Company and Lucent have agreed to negotiate in good faith to provide
various additional terms to the Lucent Purchase Agreement.  If the Lucent
Purchase Agreement is not amended and restated to add these terms by June 15,
1998, either party may terminate the Lucent Purchase Agreement.  There can be no
assurance that the parties will reach agreement on such terms and that the
Lucent Purchase Agreement will not be terminated on or after June 15, 1998.

     The Company and Lucent have also entered into a commitment letter (the
"Lucent Commitment Letter" and, together with the Lucent Purchase Agreement, the
"Lucent Agreements").  The Lucent Agreements are contingent upon various
conditions, including the execution of a definitive financing agreement,
amendment and restatement of the Lucent Purchase Agreement, compliance with
financial covenants, raising additional capital, completion of due diligence and
the absence of any material adverse change in the Company.  There can be no
assurance that a definitive agreement will be executed with respect to the
financing contemplated by the Lucent Commitment Letter or that the financing
contemplated by the Lucent Commitment Letter will be consummated. Any failure to
consummate the financing contemplated by the Lucent Commitment Letter could
materially and adversely effect the Company's business and results of
operations.

     Competition.  The industry and markets in which the Company plans to
provide services are highly competitive.  The Company competes with other
providers of telecommunications services using a variety of telecommunications
technologies, now existing and under development, including copper, fiber,
cable, mobile and fixed wireless and satellite networks, and the Company expects
to compete with technologies not yet introduced. These other technologies may
offer advantages over the Company's services.  In addition, many of the other
wireline and wireless services providers have longer operating histories, longer
standing relationships with customers, and suppliers, greater name recognition,
better geographic footprints and greater financial, technical and marketing
resources than the Company.  As a result, these competitors, among other things,
may be able to develop and exploit new technologies, adapt to changes in
customer requirements more quickly, devote greater resources to the marketing
and sale of their services or more rapidly deploy and build-out a network than
the Company.

     While the Company does not believe that any other competitor is focusing
exclusively on offering broadband data services to business customers without
fiber connectivity, ART faces significant competition from other entities and
technologies that currently, or could in the future, deliver data services to
ART's potential customers over copper wire, fiber, wireless or other
technologies.  These current or potential competitors include local exchange
carriers ("LECs"), fiber and wireless service providers and cable television
operators.  The Company's competitors also include providers of services which
are in competition with the Company's product offerings, such as Internet
service providers ("ISPs").  Moreover, the recent and pending auctions of
spectrum capable of supporting comparable services may facilitate the
introduction or expansion of competition from other 

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competitors. There can be no assurance that the Company will be able to compete
effectively with these other technologies and service providers in any of its
markets.

     The Company has only recently begun to introduce its broadband data
services and has only recently begun to pursue customers with the goal of
becoming the leading provider of broadband data services to businesses without
fiber connectivity.  To date, the Company does not have significant market share
in any of the markets in which it holds licenses.  Given the intense competition
in the market for broadband data services, there can be no assurance that the
Company will achieve significant market share in any market.

     Management of Growth.  The Company is pursuing a business plan that, if
successfully implemented, will result in rapid growth, expansion of operations
and provision of broadband data services on a widespread basis over the next two
to five years.  Rapid expansion of the Company's operations may place a
significant strain on the Company's management financial and other resources.
If this growth is achieved, the Company's success will depend on its ability to
manage this growth effectively, enhance its operational and financial controls
and information systems, and attract, assimilate and retain qualified and key
personnel.  In addition, if the Company expands its business, it will require
additional facilities for its growing operation.  There can be no assurance that
the Company will successfully implement and maintain such operational and
financial systems or successfully obtain, integrate and utilize the employees
and management, operational and financial resources necessary to manage a
developing and expanding business in the evolving, increasingly competitive
broadband data communications market.  Failure to successfully manage expansion
could materially adversely affect the Company's business, financial condition
and results of operations.

     The billing, provisioning, customer service, network management and other
"back office" systems with the functionality that the Company plans to offer do
not currently exist in a form which can be readily adopted by the Company.
Significant development work by the Company or a third-party provider will be
required to develop such systems for the Company.  Delays in developing and
implementing such systems may have a negative impact on the Company's ability to
offer the efficiency and functionality expected to be provided by these systems
and accordingly on the implementation of the Company's business plan.

     Need for Technological Development.  Although the Company is initially
deploying its network utilizing fixed wireless point-to-point technology which
has been commercially deployed for a period of time, the Company plans to
utilize point-to-multipoint technology in its networks as soon as it becomes
commercially available.  The principal advantages of point-to-multipoint
architecture over traditional point-to-point installation include lower costs
per customer installation and higher flexibility in how bandwidth is allocated.
Point-to-multipoint also makes it possible to support many more subscribers than
otherwise would be possible in a point-to-point environment. This technology has
not been deployed on a commercial basis, and it is unclear whether the
technology will perform as expected, integrate as expected with the Asynchronous
Transfer Mode ("ATM") switching gear and other components of the Company's
network, or provide the advantages expected by the Company.  Unanticipated
difficulties or delays in deploying point-to-multipoint technology or failure of
point-to-multipoint technology to yield the expected benefits could adversely
affect the Company's network costs, profitability and results of operations.

     Fixed Wireless Limitations.  The Company's wireless broadband services
require a direct line of sight between two transceivers and are subject to
distance and rain attenuation.  In certain markets which experience heavy
rainfall, transmission links must be engineered for shorter distances and
greater power to maintain transmission quality.  Such engineering changes may
increase the cost of providing service.

     The Company primarily installs its transceivers and antennas on rooftops of
building and on other tall structures.  The Company generally must secure
building access rights, access to conduits and wiring from building owners, and
may require construction, zoning, franchises or other governmental permits.
There can be no assurance that the Company will succeed in obtaining roof access
and other rights necessary to provide wireless broadband 

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services to potential customers in its market areas on favorable terms, if at
all, or that delays in obtaining such rights will not have a material adverse
effect on the Company's development and results of operations. Moreover, there
may be a limited number of available buildings which provide a clear line of
sight to targeted buildings, and therefore there may be some circumstances where
installation is impracticable or uneconomical. In such cases, the Company may
decide to provide services that are uneconomical in the short term and seek
alternative methods of transmission to provide services on a more economical
basis, or decide not to provide services to potential customers in locations
with such limitations. There can be no assurance that line of sight limitations
will not have a material adverse effect on the Company's future development and
results of operations.

     Equipment Failure and Interruption of Service.  The Company's operations
will require that its network, including leased fiber-optic connections,
operates on a continuous basis.  It is not unusual for networks including
switching facilities to experience periodic service interruption and equipment
failures.  It is therefore possible that the network and facilities utilized by
the Company may from time to time experience service interruptions or equipment
failures, which would adversely affect consumer confidence as well as the
Company's business operations and reputation.

     Dependence on Key Employees; Need to Attract and Retain Qualified
Personnel.  The success of the Company will be dependent, in large part, on its
ability to attract and retain qualified technical, marketing, sales and
management personnel.  The loss of the services of key personnel could have a
material adverse effect upon the business, financial condition and results of
operations of the Company.  The Company's ability to implement its business plan
will require the addition of significant number of qualified personnel.
Competition for such personnel is intense, particularly those experienced in
information technology, and there can be no assurance of the Company's ability
to attract and retain additional key employees and retain its current key
employees at a reasonable cost, if at all.  The failure to attract and retain
such personnel at reasonable costs could have a material adverse effect on the
business.

     Importance of Third-Party Relationships.  In addition to its relationship
with Lucent, the Company intends to enter into relationships with third-parties
to assist it in providing services, extending its network and penetrating
markets.  There can be no assurance that the Company will be able to enter into
such relationships on a time line that is consistent with the Company's
strategy, if at all.  Failure to enter into such relationships, the failure of
third parties to perform once such relationships are entered into, or the loss
of third-party relationships once entered into could cause delays in providing
services, limit the Company's reach in marketing its product, increase costs for
the Company to extend its reach and penetrate markets, and/or impede the
Company's ability to offer certain service packages to certain customers.  Such
failures could have a material adverse effect on the Company's development and
results of operations.

     Government Regulation.  The telecommunications services offered by the
Company are subject to regulation by federal, state and local government
agencies.  Changes in existing laws and regulations applicable to the provisions
of wireless data services via the Company's licenses or to the regulations
governing competitive or potentially competitive providers, or any failure or
significant delay in obtaining or maintaining any regulatory approvals which may
be required, could have a material adverse effect on the Company.

     Risk of Forfeiture, Non-Renewal and Fluctuation in Value of FCC Licenses.
The Company must comply with FCC rules relating, among other things, to its
licenses.  Failure to comply with FCC rules could subject licenses to automatic
forfeiture or, depending on the violation, to other FCC sanctions.

     The Company is required to demonstrate at license renewal that it is
providing substantial service within the authorized area covered by that
license.  There can be no assurance that the Company will be able to make this
showing for any or all of its licenses.  In the event that the FCC does not
renew one or more of the licenses, the Company's business and results of
operations could be materially adversely affected.

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     The Company's wireless licenses are integral assets of the Company, the
value of which will depend significantly upon the success of the Company's
wireless data services operations and the future direction of the wireless
segment of the telecommunications industry.  The value of licenses to provide
wireless services also may be affected by fluctuations in supply and demand for
such licenses and by valuations placed on such licenses in any current or future
auctions of spectrum, such as the FCC's recently-completed auction of spectrum
in the 28 GHz band.  In addition, federal and state regulations may limit the
ability of licensees to sell their licenses.  Assignment of licenses and changes
of control involving entities holding licenses require prior consent of the FCC
and, in some instances, state and municipal regulatory approval, and are subject
to restrictions and limitations on the identity, background, legal and financial
qualification, among other things, of the assignee or successor.  These
regulatory restrictions on transfer of licenses may adversely affect the ability
of the Company to acquire or dispose of further licenses or the value of the
Company's licenses.

     Licenses Pending Approval for Transfer.  The Company has entered into
agreements to acquire licenses from other parties to enter new markets or
strengthen the Company's position in existing markets.  Failure to consummate
the transfer of these licenses could affect the Company's ability to offer
broadband data services in certain markets where the Company intends to
commercialize its services.  The acquisition of these licenses is subject, among
other conditions, to the approval of the FCC to the assignment of, or change of
control of the entity holding, the licenses, as the case may be.  There can be
no certainty that the Company will receive the requisite approval to acquire
these licenses and thereby be able to implement its strategy with respect to the
markets covered by such licenses.

     Acquisition of Additional Bandwidth in Selected Areas.  The Company
believes the licenses it owns, manages, or has the right to acquire or use are
sufficient to fully implement its business plan.  However, the Company may seek
to acquire or manage additional licenses to expand its geographic footprint or
to enhance its ability to provide service to its current target market or
customers it may target in the future.  There can be no assurance that the
Company will be able to acquire additional radio spectrum on favorable terms or
at all.

     Changes in Technology, Services and Industry Standards.  The
telecommunications industry and market for data services has been characterized
by rapid technological advances, changes in end-user requirements, frequent new
service introductions, evolving industry standards and decreases in the cost of
equipment.  The Company expects these changes to continue, and believes that its
long-term success will increasingly depend on its ability to offer value-added
broadband data services that exploit advanced technologies and anticipate or
adapt to evolving industry standards.  The Company believes that to remain
competitive, retain the customer base it establishes and maintain the margins of
the retail market it is pursuing, its integrated package of high-speed,
broadband data services must continue to evolve to keep pace with developments
in the market.  There can be no assurance that (i) the Company will be able to
arrange to offer the new services required by its customers, (ii) the Company's
services will not be economically or technically outmoded by current or future
technologies which may compete in the data market, (iii) the Company will have
sufficient resources to develop or acquire new technologies or introduce new
services capable of competing with future technologies or service offerings (iv)
the Company's inventory of equipment will not be rendered obsolete, or (v) the
cost of the Company's equipment and network will decline as rapidly as that of
competitive alternatives.  Moreover, there can be no assurance that the
Company's ability to offer the broadband wireless data access with which it will
deliver its value-added services will not become technically or economically
outmoded as new equipment, technologies and advances in competing alternatives
become available.

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