The Global Link - Arinc

The Global Link November 2011 | #43 

The Global Link 

A Newsletter for the Aviation Industry 

Chairman’s Perspective: Customers 

Are Our Link to Success 

1. Spotlight on ARINC Managed 

Services 

2. ARINC in Asia: AeroConnx TM 

and Cathay Pacific Take a 

Big Step Together Toward 

eEnablement 

3. ARINC in Asia: Continuing 

Growth Story in Asia 

4. GLOBALink SM /HFDL: Dynamic 

Frequencies 

5. GLOBALink SM /Satellite: Inmarsat 

Aero-I Trials Over the I-4 Network 

FANS Over Iridium (FOI 

Announcement 

6. GLOBALink SM /VHF: Meeting the 

Need for Reliable VHF Voice 

Comms in the Gulf of Mexico 

7. GLOBALink SM /VHF: Growth 

Trends—Aircraft and Messaging 

8. ARINC in Latin America and 

the Caribbean: GLOBALink SM /VHF 

Service in Latin America and 

the Caribbean 

9. ARINC in Europe, the Middle 

East, and Africa: ARINC EMEA 

Accelerates Its VHF Ground 

Station Deployments 

10. ARINC OpCenter SM : ARINC 

Tarmac Delay Manager 

Graphical User Interface (GUI) 

11. Technotalk: Expanding the VDL 

Mode 2 Service for the Future: 

Exercises in Frequency and 

Spectrum Management 

2551 Riva Road, Annapolis, MD 21401 USA | +1 800.633.6882 | arinc.com

November 2011 | #43 


Chairman’s Perspective 

Customers Are Our Link to Success 

Aviation is a unique industry, with strong roots and a vital role in the world economy. ARINC 

has been there since the very beginning of commercial aviation, which affords us a unique 

perspective, but also a tremendous responsibility—a tremendous opportunity to focus that 

knowledge and experience into ideas that consistently, perpetually put our customers in 

positions in the market to succeed. 

John Belcher 

Chairman and 

Chief Executive Officer, 

ARINC 

That’s why customer feedback is so critical to every service GLOBALink SM provides. As the 

global leader in voice and data communications, we are directly influenced by the voices of 

our customers every day. Predicting their challenges and recognizing their needs allows us 

to design solutions that are safer, more secure, more efficient, and more cost-effective than 

ever before. It allows us to bring together and meld the initiatives of aviation’s governing 

bodies and the airlines themselves. It allows us to take the arc of aviation’s history and see 

over the horizon, with a vision clear and resolute into what’s next for the entire industry. 

On April 24-26, 2012, we’ll be hosting the GLOBALink Customer Meeting for the Americas 

Region at our Headquarters in Annapolis, MD. Recent advances in technology and the 

introduction of new global Telecoms services have significantly increased Aeronautical 

Operational Control (AOC) options available to airlines today. During the conference we will 

cover the latest information about these emerging air-ground communications trends and 

issues. We’ll also focus on the FAA Next Gen Data Comm Program and the status of data 

link in Air Traffic Management, as well as ARINC’s industry implementations Controller Pilot 

Data Link (CPDLC), FANS 1/A and ATN/CPDLC. 

The evolving role of dispatch and its impact on System Operations Centers (SOC) is a 

major topic today. We’ll look at ways today’s advancements will help dispatchers keep their 

airline’s command centers running smoothly and efficiently. We’ll also discuss the aircraft as 

a weather sensor and how innovations in data collection that provide real-time weather to 

the National Weather Service benefit the entire industry. And, we’ll look at access security 

services, including CASS SM and CrewPass SM , their current status, and their direction in the 

industry. 

Please visit globalinkcustomermeeting.com and fill out our Customer Meeting Agenda 

survey to let us know what issues are important to you. We hope to see you in Annapolis on 

April 24 th .



Spotlight on ARINC Managed Services 

ARINC Managed Services (AMS), the global IT support subsidiary of ARINC Incorporated, 

provides a variety of IT managed services for airports looking to improve equipment reliability, 

minimize downtime and decrease costs. A key part of that service offering is the AMS 

Service Desk. 

Contact the Author 

Although most people are familiar with the concept 

of a help desk, a service desk and the benefits it can 

provide are less widely understood. While the Information 

Technology International Library (ITIL) has differentiated 

the two terms since 2007, there remains some confusion 

about the definition, relationship and value of the two 

facets of IT support and management. 

But as the service desk model becomes more mainstream 

as a management strategy for supporting business 

operations, recognizing the distinction becomes more 

important. 

Chris Forest 

Senior Director, 

ARINC Managed Services, LLC 

tel: +1 410.956.6475 

cforrest@arinc.com 

The help desk, with its tactical focus, is geared towards end user productivity. The role of 

the service desk, however, is broader and more strategic—easily extending beyond the IT 

world to any organizational function that must manage the processes of problem reporting, 

dispatch and resolution. A service desk is, in fact, a business strategy—a way to track and 

manage processes, assets, and costs to optimize both service levels and resource utilization. 

It goes beyond user productivity to address organizational productivity. 

For many airports, for example, the AMS Service Desk operates under SLA performancebased 

contracts to provide either full or partial support for ongoing maintenance operations, 

including the support of air-to-ground communications. AMS’ in-depth knowledge and 

expertise in call handling enables us to provide customers any degree of support required, 

ranging from general product/service inquiries to first call resolution. A trouble ticket is 

generated automatically based on caller information and the incident is tracked until it’s 

resolved through systematic escalations based on predetermined business practices. 

This process-based approach and the metrics it can provide not only resolves the problem at 

hand, but also provides data for continual improvement, creating a better standard of service 

and cutting operating costs. 

The AMS Service Desk operates 24x7 and manages 40,000 calls annually for more 

than 3,000 customers in 85 countries. More information is available at 

www.arincmanagedservices.com. 

1



ARINC in Asia 

AeroConnx TM and Cathay Pacific Take a Big Step 

Together Toward e-Enablement 


Robert Lentz 

Senior Manager, 

Aviation Solutions, 

ARINC 

tel: +1 410.266.4636 

robert.lentz@arinc.com 

ARINC and Cathay Pacific’s e-Enabled Aircraft Partnership began in 2004 with a simple 

request for an electronic document viewer. Within six years, it had changed a Cathay Pacific 

B777 into a flying node on the carrier’s enterprise network, running half a dozen major new 

productivity applications. ARINC’s AeroConnx solution answers the question, “How many 

benefits can an airline derive by using an electronic flight bag?” Last March, following years 

of development and flight testing and months of operational evaluation, ARINC and Cathay 

Pacific declared their AeroConnx project an unqualified success. AeroConnx will play a key 

role in advancing Cathay Pacific’s initiative for e-Enablement, because the data it delivers 

will cut across all divisions of the company. 

ARINC and Cathay Pacific formed a technical partnership, working toward an EFB definition 

that would meet the airlines objectives. It had to present “one common look—a standard 

interface” on any Cathay aircraft. When the system was fully defined, it was a flexible, 

integrated aircraft/ground end-to-end IT infrastructure. The companies proved their concept 

viable by using an A330 simulator. Then the architecture was refined and key vendor 

relationships were established. 

In November 2008, ARINC and 

Cathay Pacific agreed to move 

forward with a full trial program of 

their solution, using a Cathay B777- 

300. There would be three EFBs 

installed in the cockpit, and one 

in the cabin. Also included in the 

solution are ARINC’s GateFusion SM 

gatelink service and GLOBALink Sm , ACARS ® and Iridium services. In 2010, a successful flight 

test and certification from the FAA and Hong Kong Civil Aviation Department occurred. Then 

Cathay and ARINC performed a six-month operational evaluation before declaring their trial 

an unqualified success. Now, Cathay and ARINC are working together to implement the 

e-Enabled solution fleet-wide. 

2



ARINC in Asia 

Continuing Growth Story in Asia 

ARINC Asia Pacific Division (APD) continues to foster close relationships with key customers 

in the region with the running of the 8 th Airline Data Link Communications and Applications 

Training at ARINC’s headquarters in Annapolis from 31 st October 2011 to 4 th November 

2011. Through this training, participants are exposed to the various topics ranging from 

familiarization with industry standards, data link applications and avionics architecture, 

current trends in aircraft communications, ACARS ® and various GLOBALink SM services 

and solutions. 


Expansion of ARINC’s GLOBALink SM /VHF network in Asia Pacific continues with the successful 

deployment of a new ground station in Brunei. This deployment provides air to ground 

coverage at Brunei International Airport and provides airline customers with seamless 

coverage across neighboring Flight Information Regions (FIR), increasing efficiency and safety 

for the airlines. Another significant deployment is also at Dunedin, New Zealand increasing 

the current number of ground stations sites from three to four. These achievements would 

not have been possible without the close coordination and support between ARINC’s project 

managers and partners. To demonstrate ARINC’s commitment to remain as one of the 

sought after datalink service providers in the Asia Pacific region, ARINC will continue to 

provide major coverage enhancement with several planned deployments and equipment 

upgrades in several countries expected to be complete by year’s end. 

Gavin Ng 

Program Manager, 

Satellite Services, 

ARINC 

tel: +65 6419.2536 

gylng@arinc.com 

ARINC APD’s commitment to support regular customer training and knowledge sharing within 

the aviation industry coupled with the GLOBALink/VHF expansion programme will continue to 

enhance ARINC’s presence in the region. 

3



GLOBALink 

Voice & Data Communications 

GLOBALink/HFDL 

Dynamic Frequencies 


ARINC has recently enhanced the HFDL service to provide faster and more efficient 

communication. Read on to learn how. 

The HFDL system is licensed to operate on 167 frequencies across 15 stations worldwide. 

John Patterson 

Principal Engineer, 

Customer Services, 

ARINC 

tel: +1 410.266.4249 

john.patterson@arinc.com 

Over the course of the 11 year solar cycle, certain frequencies will be needed during the 

different phases of the cycle. Each ground station is assigned a portion of those frequencies 

for use and the HF Radio on board every equipped aircraft (over 1600 to date!) has all 167 

frequencies loaded in its memory. So no matter where an aircraft may fly, it can scan that 

memory and find an operating frequency for ARINC HFDL. 

Scanning the table of frequencies can be time consuming for the radio, so to make the 

process more efficient and reduce search and login times, ARINC has equipped each 

station with the ability to remotely program the ground station transceivers with the most 

efficient set of frequencies for the current phase of the solar cycle. The airborne radios will 

concurrently receive frequency 

assignment updates over the 

air without any intervention 

by flight crews, engineering or 

maintenance personnel. Keeping 

the radios in DATA mode even in 

full VHF or SATCOM coverage will 

allow the radios to receive the 

updates without interrupting the 

flow of ACARS ® messages. 

This streamlining will not only 

Located in a remote section of the tundra outside the town of Barrow 

Alaska, this TCI-530 antenna delivers critical ACARS message for polar make initial search and login 

crossing aircraft. 

faster, but will also allow for more 

efficient and thorough background scanning while the aircraft is connected to the HFDL 

network. The aircraft radio maintains a dynamic list of active frequencies in its memory 

for smooth transitions across coverage areas. An efficient list of deployed frequencies 

across the HFDL network will ensure smoother transitions and keep the radio’s dynamic list 

populated with multiple options for connecting with the ARINC HFDL network, thus further 

increasing the reliability of delivering flight critical messages. 

ARINC endeavors to continually improve our customer’s experience and welcomes any 

feedback to keep HFDL hopping! 

4



GLOBALink/Satellite 

Inmarsat Aero-I Trials Over the I-4 Network 

Following an extended consultation period by Inmarsat after their annual aeronautical 

conference in June of this year, a program plan is underway to determine if Aero-I service 

characteristics can be supported over the I-4 satellite network. A coordinated test schedule 

with select aircraft and avionic sets has been planned and the operational testing should 

commence this month. Once edge of coverage issues are thoroughly analyzed and the 

resultant information is reviewed by Inmarsat, a decision should be forthcoming during the 

4 th quarter of 2011 whether Aero-I users will be granted access to the I-4s. Preliminary 

discussions indicate that if the Aero-I service is supported on the I-4s, it would only resume 

for an estimated 1 to 3 years beyond the current end-of-life of the I-3 satellite network 

which is destined for closure at the end of 2016. According to Inmarsat, this should allow 

a suitable timeframe for customers with Aero-I equipment to transition to an alternate 

technology upgrade such as Inmarsat SwiftBroadband service. 




Tom McCullough 

Director of Operations, 

Satellite Services, 

ARINC 

GLOBALink/Satellite 

FANS Over Iridium (FOI) Announcement 

tel: +1 410.266.4986 

tom.mccullough@arinc.com 

As a culmination of efforts for the FANS Over Iridium (FOI) operational trials conducted by 

the FAA-sponsored Performance Based Operations Aviation Rulemaking Committee (PARC) 

Communications Working Group (CWG), the FAA has now recommended approval of FOI in 

FANS 1/A operational airspace in a letter to the industry dated June 27, 2011. The report 

that was submitted to the FAA by the PARC CWG recommended that the FAA remove Iridium 

safety communication restrictions as FOI operations can meet the Required Communications 

Performance (RCP) 240 and Required Surveillance Performance (RSP) 180 specifications 

for reduced airspace separations. FOI enabled aircraft are now eligible for reduced 30 and 

50 nautical mile (NM) longitudinal and 30 NM lateral separations through Asia and Pacific 

regions, with reduced 25 NM lateral and 5-minute longitudinal separations planned for the 

North Atlantic region. This decision was a significant one for aircraft operators who value 

safety service use across various aeronautical communications media today. 

5





GLOBALink/VHF 

Meeting the Need for Reliable VHF Voice Comms 

in the Gulf of Mexico 


In the past ten years, the level of air traffic through the Gulf of Mexico has increased 

in volume and importance. This trend is a result of the growing commercial and tourist 

business between the U.S. and Central and South America, low-cost carriers expanding 

new routes into Mexico and the Caribbean, and the increased emphasis on precise aircraft 

location and identification associated with Homeland Security functions. A key component 

to cost-effective route structures and reduced separation standards for aircraft operating 

through the Gulf of Mexico is reliable VHF voice communications. ARINC supports this need 

with two VHF radio networks: VERN and GulfNet. 

Kim Wellschlager 

Engineering Program Manager, 

Aviation Voice Services, 

ARINC 

tel: +1 410.573.3565 

kimberly.wellschlager@arinc.com 

The VHF Extended Range Network (VERN) voice radio system was established by ARINC in 

1998 in response to an FAA requirement to enhance direct pilot-to-controller VHF voice 

communications in portions of the Gulf of Mexico. VERN is operated from three landbased 

(coastal) radio sites: Key West, Florida; Cancun, Mexico, and Merida, Mexico. The 

system provides coverage for portions of the Houston Oceanic FIR at FL180 and above 

using proprietary design techniques to attain extended range capability. These techniques 

include high-power linear amplifiers, radio signal processing components, unique tower site 

locations, and use of high-gain, directional antennas. ARINC designed, built, and integrated 

a remote maintenance monitoring capability for each station, and integrated the network 

with the FAA Voice Switching Communications System at the Houston ARTCC. The VERN 

sites are connected to the ARTCC by dedicated telecom links and continuously monitored 

by ARINC’s New York Communications Center. Recent improvements to the system include 

Voice over Frame Relay connectivity and new, multi-mode digital radios, improving voice 

quality, reliability and real-time monitoring. ARINC is currently under contract with the FAA 

to provide VERN through March 2012. 

ARINC operates an additional network of six VHF voice stations (GulfNet) to provide AOC 

communications and ATC relay for parts of the Gulf of Mexico and the Caribbean WATRS 

Plus airspace. The ARINC Radio Operator (RO) can relay information via telephone or 

teletype and initiate phone patches upon aircrew or dispatcher request. The ARINC GulfNet 

includes six land-based sites: two sites in Mexico, one site located on an off-shore oil 

production platform in the Gulf of Mexico; Key West, Florida; Nassau, Bahamas; and a site 

at San Juan, Puerto Rico. GulfNet is primarily used for AOC communications and under 

contingency situations to relay position reports and ATC messages for the Miami or Houston 

ARTCCs. GulfNet complements the coverage provided by VERN; however, it is not designed 

for direct pilot-to-controller communications or extended range capability throughout the Gulf 

of Mexico. 

Both VERN and GulfNet are in-place services with proven operational effectiveness that 

support the industry’s requirement for reliable and sustainable voice communications in the 

Gulf of Mexico. 

6



GLOBALink/VHF 

Growth Trends—Aircraft and Messaging 



An interesting trend has become evident in the world of data link communications. Old or 

otherwise inefficient aircraft being removed from service are being supplanted by deliveries 

of new and more efficient aircraft, so the total number of aircraft using the GLOBALink SM 

network has remained relatively unchanged. Yet we continue to see sustained growth in 

network usage—remarkably so over the VDL Mode 2 and HFDL data link networks. 


Nearly 25% of all aircraft using the GLOBALink SM /VHF network today are VDL Mode 2 

equipped, with those aircraft accounting for over 33% of the message traffic in North 

America and 20% of total worldwide network traffic. ARINC is rapidly expanding its VDL 

Mode 2 coverage; to date we boast almost 400 ground stations covering 20 countries. But 

consider that most areas of the world—more than 1,000 ground stations covering 106 

countries—operate using analog data link or Plain Old ACARS ® (“POA”). This means that 

the 2,800 VDL Mode 2 equipped aircraft using the GLOBALink network today are clearly 

responsible for a significantly higher proportion of all GLOBALink/VHF message traffic. 

Another interesting trend is that of the increased ratio of uplinked message traffic to 

downlinked message traffic. A growing number of aircraft operators are taking advantage of 

data link applications (for example FMS Flight Plans uplinked to the cockpit) creating greater 

operational efficiencies and reducing overall costs. This has become increasingly common 

as airlines make the migration to the faster VDL Mode 2 digital technology. 

Barbara Carlsson 

Senior Business Manager, 

GLOBALink Data and Information Services 

ARINC 

tel: +1 410.266.2198 

bjc@arinc.com 

Just as the number of VDL Mode 2 equipped aircraft using the GLOBALink/VHF network 

increases, the number of HFDL aircraft using the GLOBALink SM /HF network continues its 

steady rise. Worldwide approximately 200 HFDL aircraft come into service every year, 

resulting in a solid 5% to 10% growth in message usage. Many new aircraft are delivered 

with HFDL as a standard feature, an option used by many airlines to complement Satellite 

data link communication on long range aircraft. The current number of 1,600 HFDL aircraft 

is predicted to increase throughout all regions of the world. 

The growth that both the HFDL and the VDL Mode 2 networks is experiencing is not 

unexpected—ARINC planned for this, and we continue to proactively plan and invest in 

both services. Recent enhancements to the HFDL network (such as Dynamic Frequency 

Management as described by John Patterson in this newsletter) have resulted in improved 

performance and faster transmit times. Deployment of VDL Mode 2 is rapidly expanding 

worldwide—throughout Europe, Asia, and Latin America. ARINC has its finger on the pulse 

of ATC future requirements and is anticipating the needs of the aviation community. The 

GLOBALink/HF and GLOBALink/VHF networks were developed by and are wholly owned 

and operated by ARINC. The steady growth in these networks has resulted in continued 

investments and long-term planning to meet ARINC’s corporate commitment to provide the 

highest quality of service. 

7



ARINC in Latin America and the Caribbean 

GLOBALink SM /VHF Service in Latin America and 

the Caribbean 


Veronica Fernandez-Lozano 

Business Manager, 


ARINC 

tel: +1 410.266.4008 

veronica.lozano@arinc.com 

ARINC has a long and established history of providing GLOBALink SM /VHF Service in the 

Latin America and Caribbean region. In 2001 we began a comprehensive ten-year program 

to expand our VHF, HF data link and voice coverage to meet the region’s rapidly growing 

demands. During this ten-year period coverage has expanded from the original thirty-three 

ground stations to one hundred and thirty—one hundred and fifty ground stations if we 

include our partnership with DECEA in Brazil! Ten more GLOBALink/VHF ground stations 

will be deployed in 2011. Furthermore, the program has been extended to support the 

continued growth in the region. 

In addition, ARINC continues to increase its presence in this dynamic region. In 2001 

we were operating in ten countries; today our reach extends to thirty-eight countries, 

with plans to add VHF ground stations in two more countries this year. 

ARINC’s VDL Mode 2 expansion project also continues in the region; we now have 

extended our coverage and provide VDL Mode 2 service in six locations—Mexico City, MX; 

Georgetown, BWI; Providenciales, Turks & Caicos; Kingston, Jamaica; Aguadilla, PR; 

and Antigua. 

Annual VHF data link traffic went from nine million kilobits in 2001 to forty million kilobits 

today. Their increased use of data link applications shows how our airline customers have 

benefitted from the value of our service. 

Most importantly we have consistently exceeded all our availability targets, demonstrating 

our reputation for providing the highest quality of service. Our commitment to provide 

outstanding customer service and support remains our priority. We are proud to provide our 

services to the majority of airline carriers in these important and fast growing regions and 

will continue to strive to exceed their expectations. 

It has been very exciting for ARINC to have played an integral part in our airline customers’ 

growth and prosperity over the past ten years. We look forward to supporting their continued 

growth through coverage expansion and service enhancements in the years to come. 

8



ARINC in Europe, the Middle East, and Africa 

ARINC EMEA Accelerates Its VHF Ground Station 

Deployments 

Over the past decade ARINC EMEA has made a substantial investment in expanding its 

GLOBALink SM /VHF infrastructure to successfully meet the requirements and needs of our 

rapidly growing customer base. During this 10 year period, we have deployed over twohundred 

(200) VHF Ground Stations throughout the EMEA region which are relied on by 

more than fifty airlines and two-thousand (2000) aircraft for their seamless air to ground 

communications. Our commitment to continually expanding and improving our GLOBALink SM 

network along with our drive to provide exceptional value and personalized service is 

the foundation relied on to retain our very important existing customer base and is the 

springboard to attract many new airline customers to ARINC. 

However, our investment doesn’t stop here, as we now plan to significantly accelerate our 

VHF ground station investment over the next two years. During this period, we plan to deploy 

eighty-five (85) additional VHF Ground Stations in the EMEA region as well as Pakistan and 

India. As such, in just two year’s time (by 2013) we plan to expand our current Network 

infrastructure by more than 40 percent to optimally serve our customers. 


Michael DiGeorge 

Sr. Program Director, 


ARINC 

tel: +44 7918.720.635 

md@arinc.com 

ARINC EMEA’s accelerated investment plan demonstrates our commitment and focus on 

meeting our existing and prospective customer requirements, establishing ARINC as the 

pre-eminent data link service provider in the EMEA region and reinforcing ARINC’s position 

as the world leader in data link communications. 

9




In-Flight Applications 

ARINC OpCenter 

ARINC Tarmac Delay Manager Graphical User 

Interface (GUI) 


The U.S. Department of Transportation has implemented new rules to prevent long tarmac 

delays for international passengers which impose fines on U.S. and international airlines if 

they leave an international flight on the tarmac for more than four hours without taking off 

or deplaning. 

Yuri Maslov 

Senior Program Manager, 

GLOBALink Information Management, 

ARINC 

tel: +1 410.266.4504 

yuri.maslov@arinc.com 

On May 12, 2010 ARINC announced an automated alerting capability to help airlines 

manage flight delays on the tarmac and avoid penalties under strict DOT regulations. 

To make this feature even more efficient, the ARINC OpCenter SM team has developed a 

Graphical User Interface (GUI) that adds significant flexibility for airlines to drive 

customized solutions. 

The ARINC Tarmac Delay Manager GUI is a very intuitive and yet comprehensive tool. It 

provides complete control to airlines to configure unlimited uplinks per “OUT not OFF” or 

“ON not IN” events and to establish the same rules for all airports or modify triggers 

based on time of day and/or airport. 

The ARINC Tarmac Delay Manager GUI is available as a new feature within the ARINC OpCenter data link message 

management tool. 

10



Technotalk 

Expanding the VDL Mode 2 Service for the Future: 

Exercises in Frequency and Spectrum Management 


It’s hard to imagine, but the VDL Mode 2 service, which first went operational in November 

2000, has now been in operation for 11 years. Today, ARINC has approximately 2,700 

aircraft sending over 8 million messages per month on the GLOBALink SM /VDL service. We’ve 

come a long way (see Figure #1). These messages account for over 18% of the ACARS ® 

traffic sent over GLOBALink SM /VHF. 

We are now seeing an accelerated movement to VDL, based on a number of industry 

factors. First, with the success of the Link2000+ program, EUROCONTROL has announced 

their plan to expand the CPDLC service across Europe and mandated the need for ATN/VDL 

equipage. Second, in North America, the FAA has announced plans to proceed with the 

NexComm program, which initially is envisioned to be based on FANS (Future Air Navigation 

Service) applications transported over the VDL Mode 2 communications media, followed 

by the ATN applications over VDL Mode 2. Finally, with much of the legacy ACARS avionics 

systems becoming obsolete, most airframe manufacturers are now delivering newer aircraft, 

such as the A380 & B787, with VDL Mode 2 capable CMUs and VDRs as standard. 

Steve Leger, Director, 

Testing and Support Services, 

ARINC 

tel: +1 410.266.2169 

srl@arinc.com 

The VDL Mode 2 media, including both the airborne and DSP provided ground network, have 

demonstrated the best performance of all ARINC GLOBALink SM media. ARINC’s VDL Mode 2 

service has an uplink message success rate of over 99.0% and an average round trip transit 

time (uplink sent to downlink ACK reception) of 1.9 seconds. (See Figure #3) 

Currently all VDL Mode 2 communications are being sent on a single VDL Mode 2 frequency 

or channel on 136.975 MHz which is called the Common Signaling Channel (CSC). ARINC 

constantly monitors usage and capacity—right now, even at the busiest of USA locations, 

the CSC is still moderately loaded and can support plenty of additional traffic. Still, the 

VDL Mode 2 concepts (defined in AEEC Specification 631) are particularly complicated 

and changing the operation of this system by adding additional frequencies relies on both 

avionics and DSP updated functionality. To successfully develop and ensure interoperability 

this work must begin several years in advance of the operational need. This effort is well 

under way. 

ARINC Development of the VDL Multi-Frequency AQP/Interoperability 

Test Facility 

As discussed in a previous article, over the last 1-2 years, avionics manufacturers such 

as Rockwell-Collins and Honeywell have been busily developing VDL Multi-Frequency 

functionality within the data link units. Likewise, ARINC has been developing the protocols 

within the ground infrastructures. Almost 12 months ago, ARINC opened a special dedicated 

11



Technotalk 

Expanding the VDL Mode 2 Service for the Future: 

Exercises in Frequency and Spectrum Management 

—Continued 

test facility within the AQP labs in Annapolis. Along with the facility, a set of test cases 

were released to the industry based on ARINC’s planned approach for VDL multi-frequency 

operation. Through a course of interactive testing, ARINC and the manufacturers have arrived 

at implementations that will fully support the operation on VDL alternate frequencies. From 

a protocol and network standpoint, we are nearly ready for the future. In order to expand the 

VDL capacity, we must, of course, have assigned frequencies, and that is another ongoing 

industry activity that ARINC is supporting. 

ASRI AFC VDL Mode 2 Spectral Plan for the USA: 

Within the USA, all VHF frequencies used by the aeronautical industry for both voice and 

data applications are licensed, assigned, and managed by Aviation Spectrum Resources 

Incorporated (ASRI). ASRI was previously part of ARINC Incorporated, but became a separate 

company, owned by the airline community, when the ownership of ARINC was transferred 

to the Carlyle Group, a non-airline entity. Approximately 15 years ago, the 136 to 137 MHz 

VHF band was added to the existing aeronautical 118 to 136 MHz band. This 1 MHz band 

was primarily intended to be used for the VDL Mode 2 service. The FAA received the lower 

136.025 to 136.475 MHz portion of the band for ATC applications; ASRI received the 

upper 136.500 to 136.975 MHz portion of the band for airline operational control (AOC) 

applications. 

In mid-2010, ASRI created a special VDL spectral planning sub-working group under its 

primary technical committee, the Aeronautical Frequency Committee (AFC), which meets 

several times each year. Both ARINC and SITA were designated as co-chairmen for this 

special VDL planning group. Over the course of a year, and a series of meetings, ARINC has 

been a lead contributor, providing the propagation, testing, analysis, and much of the writing 

associated with this group. 

Engineering studies prove that the higher the data rate of any communications system, the 

more prone the system can be to interference. The VDL Mode 2 service, using Differential 

Eight Phase Shift Key (D8PSK) modulation operates at a data rate that is 15 times faster 

than ACARS. Likewise, a successful VDL deployment requires DSPs to provide coverage in 

multiple locations within the same airport infrastructure to provide reliable communications at 

each gate location. These close range stations can easily cause interference between ARINC’s 

own stations as well as the VDL stations that could be operated by another DSP in the 

regions. A successful VDL Mode 2 Spectral Plan is needed to address each of these special 

requirements. 

12



The ASRI AFC team is now reviewing an ARINC-proposed VDL Spectral Plan that will also be 

shared with the European community including the Frequency Management Group (FMG). 

It sets up a plan that includes controls such as special notch filters, careful antenna-toantenna 

spacing, and transmitter power setting. The plan provides for three terminal-area 

VDL channels in the ASRI-controlled band. These would be the CSC, VDL Alternate #1, 

and VDL alternate #2. The Spectrum plan also provides for a very large number of en route 

alternate VDL frequencies. The success of this and any other successful communications 

system deployment starts with a link budget analysis. Please refer to our August 2006 

Technotalk article which explains the analysis associated with link budgets. The resultant 

plan will be more than sufficient to address all airlines’ AOC needs for the next decade and 

onward. 

As always, please contact me if this article has raised questions or if you’d like further 

details in the VDL spectral plan. I am always interested in your suggestions for future 

articles. 

Figure #1: Growth in VDL Mode 2 AOA Aircraft and Traffic 

Figure #2: Ratio of VDL M2 AOA vs. Total VHF Traffic - 18% 

Figure #3: VDL Mode 2 Uplink Delivery Transit Time: Avg 1.9 seconds 

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The Global Link - Arinc

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