About Us


to70 is one of the world’s leading aviation consultants providing research and advisory services to the global aviation community.

to70 was founded in The Netherlands in 2000 and has since expanded with offices in Europe, Australia, Asia and Latin-America. Our clients include airports, airlines, governments and air navigation service providers. At to70 we believe that society’s demand for transport and mobility can be met in a safe, efficient, environmentally friendly and economically viable manner. To achieve this, policy and business decisions have to be based on objective information. With our diverse team of specialists and generalists to70 provides pragmatic solutions and expert advice, based on high-quality data-driven analyses.

Mission: Enable aviation and society to cope with current and future challenges for airport and airspace operations, by delivering outstanding research and consultancy services, profitably.



It is quite a challenge to make sure that real estate projects and air traffic procedures are not conflicting. I translate regulations and flight safety guidelines into maps, 3D-models, GIS data and interactive applications to help policy makers, airport authorities and urban developers to solve this complex puzzle.

Jonas van Straaten

Aviation Consultant

With a passion for logistic processes I find aviation intriguing. What I like the most about working at To70 is to achieve results in a team and the diversity of the projects. As an aviation consultant I have experience in safety studies, airspace design and A-CDM.

Karin Elbers

Aviation Consultant

Wherever new airports are developed or existing ones are expanded, I support their masterplan design ensuring the infrastructure will meet the forecasted traffic demand. Similar capacity studies are carried out when the airspace is being redeveloped. These and many more activities are undertaken to bring value to our clients.

Michael Portier

Managing Director Singapore

I have been providing support for both the managing directors as well as the consultants with all of their administration queries. Furthermore, I am responsible for the project administration. I have also been involved in organizing the activities to support the great ambiance at our offices.

Nicoline Beunders

Office Management Netherlands

What is appealing to me at to70 is the diversity of projects and customers related to aviation. Currently I am working on projects related to obstacle assessment based on PANS-OPS and the LIB-application for Amsterdam Airport Schiphol.

Haiyun Huang

Aviation Consultant

After having worked for 11 years in the Dutch aviation industry and seeing the huge potential of the Colombian aviation industry, I decided to apply that knowledge and experience, together with that of the whole to70 team, in helping the Colombian aviation sector to cope with the challenges that come along with its growth.

Peter Gal

Managing Director Colombia

An ounce of practice is worth a ton of theory. I’ve brought along a career of 25+ years in airport operations to support our customers in implementing Airport Collaborative Decision Making (A-CDM) and operational performance reporting. Having ‘been there and done that’ since the early days of the concept allows me to tackle the real concerns of A-CDM implementation: culture change and stakeholder engagement.

Kris de Bolle

Senior Aviation Consultant

Prawit Otanalai

Aviation Consultant

Providing strategic advice and optimising the operation of airports around the world is what we do. After starting out in our Dutch office in 2004, I spent six years in Australia, working for all major airports and expanding our presence in Asia. Early 2015 I returned home to jointly manage our Dutch office and shape the global future of to70.

Ruud Ummels

Managing Director Netherlands

Wenjing Zhou

Managing Director China

As an aviation consultant she has experience in various aspects of aviation, ranging from community engagement processes to safety management studies.

Maya de Best

Aviation Consultant

To70, I believe, is the perfect platform to put my theoretical knowledge into practise. With Indian aviation market experiencing tremendous growth and new airports under consideration, I wish to address critical issues of the Indian aviation market, which aims to be the third largest by 2020 and the largest by 2030.

Arjun Puttabakula

Managing Director India

Of all the work I do at to70, fast time simulation is what I like most. To bring airports and airspace to life using state of the art software while providing our clients with all desired performance indicators. In my two years at to70 I went to Singapore, Thailand and Taiwan which indicates the international character of to70.

Ruud van Gils

Aviation Consultant

Phatcharaphong Mala

Aviation Consultant

Maarten Tielrooij is aviation consultant with a focus on Data Science and Air Traffic Management. With 8 years experience in operational ATM he is familiar with both current operations and concepts under development. He is an experienced user of programming software, modeling and simulation techniques, large databases, and statistical techniques.

Maarten Tielrooij

Aviation Consultant

Air traffic is expected to increase in the future, making sure the current airspace is capable of handling this increment will be crucial. Providing expert advice and executing the necessary changes to the airspace design and airport infrastructure efficiently without compromising safety is my goal.

Radesh Nagaraj

Managing Director India

Ensuring the best outcome for the customer is what it’s all about. I have enjoyed over 30 years in the field of air traffic management, beginning in air traffic control, before moving to airport and airspace planning, airport capacity enhancement, safety, and policy advice. Along the way, I’ve worked to ensure that the aviation projects, I’ve been involved with are performance driven and meet their targets. I believe that this is a key factor in their successful delivery.

Matt Shepherd

Senior Aviation Consultant

Since I started here, I contributed in projects related to noise modelling, third party risk assessments, fast-time-simulations studies and aeronautical studies. The projects at to70 are very diverse and challenging, which makes this job very interesting.

Vincent Bijsterbosch

Aviation Consultant

Meet Our Clients

Our consultants work in close cooperation with our clients

and are renowned for their drive to assist them in realising their short- and long-term goals.

An overview of our clients can be seen in the map below.

Interested in joining our team?