The government coalition of Social Democrats and Greens laid the foundation for the development of a surveillance drone as early as 2001. Five defense ministers came and went during the planning and trial process of the Euro Hawk unmanned aircraft. Warnings of flight permit problems came early. Here's what happened between the project's start in 2001 and its sudden end in 2013.

2001

As a member of the SPD/Greens coalition government, Defense Minister Rudolf Scharping (SPD) planned the commission of a surveillance drone that would fly at a height of 20 kilometers (12 miles) and registers radio and radar signals with the help of modern technology. US defense technology company Northrop Grumman was to be tasked with production, while European aviation firm EADS was to develop the surveillance technology. That was as far as plans went.

2003

During Peter Struck's (SPD) term as defense minister, America's Global Hawk performed its first test flights in German air space. That drone served as the prototype for the "Euro Hawk." The six successful flights laid the foundation for cooperation between the companies involved and the German defense ministry that followed.

2004

The Bundeswehr asked EADS and Northrop Grumman to present an offer for the development, production and delivery of a Euro Hawk.

Then came the first words of caution. An EADS employee warned that an anti-collision system was necessary, particularly during departure and landing. On other occasions, similar warnings came from air traffic controllers, the private sector and the German military itself.

2005

In November, EADS and Northrop Grumman founded the 'Euro Hawk GmbH' corporation. In December, they presented their bid. Public announcements about the project appear not to have been made.

Looking back, Franz Josef Jung (CDU), the defense minister at that time, recently told the German weekly "Bild am Sonntag" that the contract included an automatic anti-collision system and a "recourse clause."

2007

The budget committee in Germany's lower house of parliament approved the program in late January 2007. The defense ministry signed a 430-million-euro ($560-million) contract with the Euro Hawk GmbH corporation for the drone project.

2009

According to current reports in "Spiegel" magazine, German military inspectors pointed out potential flight permit issues in summer 2009. They criticized the manufacturer for not providing any approved construction documents that would have facilitated the obtaining of those permits. It also remains unclear whether members of the German army were even authorized to issue flight permits for the drone.

But under pressure from the defense ministry, with Karl-Theodor zu Guttenberg (CSU) as minister, a military inspector eventually carried out the necessary tests allowing for a temporary permission of flight.

2010

In June, the Euro Hawk took off for the first time. It flew from the Northrop Grumman plant in Palmdale, California to the Edwards Air Force Base in the same state. The flight lasted two hours.

2011

On July 20, the aircraft embarked on its way to Germany and landed on Manching air field near Ingolstadt after 22 hours in the air.

Officially, this was seen as a success and hailed as the beginning of a new era of surveillance. At the time, the drone had a temporary traffic permit and could only take off and land in restricted air space.

There were reports that contact was temporarily lost with the drone during the flight and that it had deviated from its programmed route. US security authorities had denied overflight permission for the Euro Hawk within the United States.

Toward the end of 2011, the German defense ministry under current minister Thomas de Maizière (CDU) discovered that flight permits would cost an additional 500 to 600 million euros.

2012

In early 2013, the drone flew for six hours over Germany, marking another test flight that was viewed as a success.

But Defense Minister de Maizière stopped the drone project in May because of massive problems in obtaining flight permits for European airspace. Construction documents were missing for some 120 Euro Hawk components. Amid growing criticism, de Maizière also announced his ministry's decision to deliver sensitive Euro Hawk documents uncensored to Germany's Federal Court of Auditors.

A short while later, Northrup Grumman and EADS issued a joint statement contradicting the defense ministry. "Media reports that indicate there are challenges with the aircraft's flight control system, as well as excessive costs associated with completing airworthiness certification, are inaccurate," they said.

The full Euro Hawk system, the companies added, performed flawlessly and safely throughout the entire flight test program.

The defense ministry grounded its decision to suddenly the Euro Hawk program on the expected additional costs of up to 600 million euros.