DBT Attorneys at Law
partnership mbB

The law firm DBT Rechtsanwaltspartnerschaft was founded on the law firm of Frank Dörner, which opened as an individual law firm in 2014. At the beginning of 2021, lawyer Kai-Alexander Bischoff joined the firm, and the partnership Dörner&Partner mbB continued to run the firm. With the further
The addition of Monika Thürmer in 2023 has expanded and supplemented our expertise.
Monika Thürmer joins the firm as a partner, and since 01.01.2024 the firm has been trading as
DBT Rechtsanwaltspartnerschaft mbB.

The three partners in the firm complement each other with their different professional backgrounds. Frank Dörner’s focus on public law and aviation law is based on 15 years of experience in planning law, public construction law and management of company-owned business jets and helicopters, immission control law as well as around 20 years of consulting, training and representation in the field of aviation.

Kai-Alexander Bischoff has extensive experience in all areas of commercial law. He has also been advising clients in the aviation sector for many years and has worked as an in-house lawyer for various corporate groups for the support and management of the aviation industry.

company’s own business jets and helicopters. Like Frank Dörner, he spends his free time flying all kinds of sports aircraft.

Monika Thürmer complements the firm with her more than 30 years of experience as a judge, particularly in the area of public law. With her experience from the other side of the courtroom, she offers an inexhaustible pool of experience and decisions from administrative law, aviation law, higher education law, railroad and mining law and other areas of public law. Her expertise in aviation is also motivated both professionally and by her own leisure flying.

© Michael Aust

Frank Dörner

Specialist lawyer for administrative law
Aviation Expert

Frank Dörner is the founder and partner of our DBT Rechtsanwaltspartnerschaft mbB and has been active in the world of aviation since his youth. Frank Dörner has built up his very broad knowledge at various levels, not only through his many years of advising clients as a lawyer in aviation law matters, but also through his activities as a lecturer, author, aviation expert and flight instructor.

As a result, he is a regular participant in various panel discussions and was invited by the German Bundestag in 2020 to comment on and assess the situation due to his practical experience with the Aviation Security Act

Qualifications and professional positions

as of 2020

Lecturer at GmbH


Invited and heard by the German Bundestag as an expert within the framework of the legislative process

Speaker and participant as an expert in panel discussions at well-known industry events, such as aviation trade fairs (Aero Friedrichshafen, European Aviation and Flightschool Congress)


Lecturer in aviation law at the technical school in Augsburg


Partner and founder of the law firm with more than 20 years of experience in aviation law


Lecturer for aviation law at the Aero-Academy GmbH

Regular publications on aviation law in the aviation trade journal aerokurier, Fliegermagazin, Adler, Luftsport, Flügel, General Aviation News, etc.

as of 2014

Publicly appointed and sworn aviation expert, IHK Munich

as of 2012

Aviation expert (certified by the VdL e. V.)

as of 2006

Legal Counsel of the Luftsport-Verband Bayern e. V.


Partner at the law firm Heinrich & Dörner, Munich


Lawyer in the law firm Meidert & Colleagues, Augsburg and Munich

Legal studies at the University of Augsburg

Qualifications in aviation

1986 glider license, 1996 glider instructor

1990 motor glider license, 1998 motor glider instructor

1994 microlight license, 2002 microlight instructor

2000 powered flight license, 2003 powered flight instructor

Kai_Bischoff© Michael Aust

Kai Alexander bishop


Kai-Alexander Bischoff joined Frank Dörner in 2021 as an additional partner. Even as a Magistrand of Deutsche Lufthansa AG, he dealt with the Group’s aviation law issues and, as Legal Counsel of Knorr-Bremse AG, looked after the company’s business jets, among other things.

Kai-Alexander Bischoff was also responsible for the company’s aviation activities for the Brose Group and was able to put his personal passion for flying to professional use. He also has many years of experience in the automotive and rail sectors, which further expands the firm’s expertise.

Qualifications and professional positions


Deputy General Counsel of the Brose Group with responsibility
for advising and supporting the Group’s aviation activities


Head of the Service Line Contract and Claim Management of the corporate legal department of Knorr- Bremse AG


Head of Legal and Insurance at Knorr- Bremse GmbH, Mödling/Austria with responsibility for the CEE countries


Specialist course for commercial and corporate law


Responsible (on the owner side) for the business jets of the Knorr- Bremse Group


Partner at the law firm Dr. Brenninger & Bischoff, Regensburg/Munich


Magistrand at Deutsche Lufthansa AG, Frankfurt/Main, in the area of corporate politics

Master’s degree: “European and International Law” (LL.M. EUR.) at the University of Bremen


Admission as a lawyer in Bremen
Legal clerkship in Augsburg with optional internship at the German-Danish Chamber of Commerce in Copenhagen Law studies at the University of Regensburg and Oslo, Norway

Qualifications in aviation


powered flight license

© Michael Aust


Lawyer, presiding judge

at the Hessian Administrative Court a. D.

After Mrs. Monika Thürmer had completed her active service at the Hessian Administrative Court, she decided to make her many years of experience available to our law firm after her admission as a lawyer from January 2022. With Ms. Thürmer, we can offer our clients excellent first-hand advice in all procedural and administrative court matters.

Not only through her proceedings as presiding judge for aviation law of the 9th Senate and the disciplinary senates, but also through her activities, Ms. Thürmer was able to gain far-reaching insight on very different fronts. Before joining the Senate for Aviation Law, she was a member of the board of the Mainz-Finthen Aviation Association and the Rhineland-Palatinate Air Sports Association. She has lectured as an aviation expert at various events and, like the entire Air-Law team, she regularly takes to the skies and enjoys flying to the full.

Qualifications and professional positions

since 2023

Co-author of the commentary by E. Giemulla on the Air Traffic Act

since Dec 2021

Attorney at Law

since Dec 2021

Presiding Judge at the Hessian Administrative Court a. D.

since May 2012

Co-editor and co-author of the Beck online commentary on Hessian higher education law


Presiding Judge at the Hessian Administrative Court

2020-2021 Chair of the 2nd Senate, which is responsible, among other things, for road and path law, railroad law and mining law

2015-2021 Chair of the Federal and State Disciplinary Tribunals

dec 2012-2020 Chair of the 9th Senate, responsible inter alia for aviation law.


Presidential Advisor for organizational matters and IT


Member of the board of directors of Luftfahrtverein Mainz e. V. (Mainz-Finthen airfield) and 2002-2005 in the
Air Sports Association Rhineland-Palatinate e. V.


Judge at the Hessian Administrative Court

2005-2012 in the Senate for Aviation Law


Judge at the Darmstadt Administrative Court


City Councillor and Head of the Legal Affairs, Economic Development and Equal Opportunities Officer at the City of Meschede in the Hochsauerland district


Legal studies at the Philipps University in Marburg, followed by legal clerkship

Qualifications in aviation


powered flight license


CVFR Eligibility


Technical course engine attendant

Claudia_Ott© Michael Aust


LL.M. (IT law)
Business Economist International Management (Univ.)
Auditor ISO 9001 & EN 9100

Claudia Ott joined the law firm in mid-2021.
After studying law and business administration, she first came into contact with aviation as General Counsel of Berger Lichttechnik GmbH & Co. KG, which is a supplier to Airbus, among other things.

She oversaw other aviation projects for the company owner and thus obtained her own pilot’s license for helicopters. Together with her passion for paragliding, she is also able to optimally combine professional and private life.

Qualifications and professional positions


Freelance business development consultant (2019-2021)


Further training as an auditor for ISO 9001 and ISO 9100 at TÜV Süd (2020)


Legal Counsel of Berger Lichttechnik GmbH & Co. KG, Pullach and support of international projects of the company and owner (2016-2019)

Until 2016

Legal Counsel at Peters, Schönberger & Partner, Munich (2016)


International management studies at the Fernuniversität Hagen (2015-2016)


Masters degree from the University of Aberystwyth, Wales
LL.M. in Technology Law


Working student at Telefónica Deutschland GmbH, Munich (2014)


Supervision of international research projects as a working student in the legal department of the Max Planck Society in Munich


Legal studies at the LMU Munich

Aviation Qualifications


paragliding license


helicopter flight license