A graduate in German, Jake has a passion for history and regional aviation, and enjoys sampling new carriers and aircraft. He has visited OEM facilities as far and wide as Bristol, Toulouse, and Seattle, and recently enjoyed the milestone of flying his 150th sector as a passenger. Based in Norfolk, UK.
Earlier on Tuesday, an emergency involving a Corendon Airlines Boeing 737-800 caused 
Nuremberg Airport (NUE) in Germany to stop its operations. The narrowbody twinjet was flying to Bavaria from Ioannis Kapodistrias International Airport (CFU) on the Greek island of Corfu when its crew changed its squawk code to '7500,' which indicates a hijacking or other unlawful interference to air traffic control.
With controllers then struggling to make contact with the pilots of the Corendon Airlines flight, German authorities opted to dispatch fighter jets to escort the Boeing 737 to its destination. In the meantime, Nuremberg Airport was closed while those involved worked to determine whether or not the situation posed a genuine threat. All is well now, but there has been a lot of knock-on disruption as a result.
Escorted By Fighter Jets
Corendon Airlines flight XR456 is a regular service from Corfu to Nuremberg. Today, tracking data from Flightradar24 shows that it left the Greek island at 11:05 AM local time, operated by a Boeing 737-800 that bears the registration 9H-CXD. However, social media coverage of the incident by Flightradar24 shows that, shortly after taking off from Corfu, the aircraft transmitted the hijacking squawk code 7500.
The squawk lasted from 11:15 AM to 11:28 AM Greek time, while the aircraft was still climbing away to the northwest. It then continued its journey to Nuremberg as normal. According to The Independent, Corendon Airlines has said that the signal was sent in error due to a radio malfunction, but German authorities didn't want to take any chances, and dispatched fighter jets to escort the plane. Local police said that:
"From the cockpit, the code '7500' (hijacking case) was transmitted, and, furthermore, the pilot could no longer be reached by radio. For safety reasons, various alarm scrambles were then triggered."
A Safe Landing
As seen in the animated map above, Corendon Airlines flight XR456 had a relatively straightforward route to Nuremberg, and it landed there just one minute behind schedule at 12:16 PM local time, after two hours and 11 minutes in the air. Thereafter, the Eurofighter Typhoon military planes that had been escorting it to Nuremberg returned to their base, satisfied that the jet had landed safely.
However, the situation was far from over at this point, with the relevant authorities first having to undertake, as the local police force put it on social media, "on-site inspections" of the aircraft. These, Polizei Mittelfranken said, subsequently "determined that there is no danger." This meant that passengers and crew could disembark, but only at 1:33 PM local time, some 76 minutes after the aircraft initially landed.
In order to allow the relevant procedures to be undertaken, reports emerged that Nuremberg Airport would subsequently be closed until 2:00 PM UTC (4:00 PM local time). As far as 9H-CXD, the Boeing 737-800 that transmitted the squawk 7500 code, is concerned, the jet was scheduled to leave Nuremberg again at 2:00 PM local time for Gran Canaria (LPA). Clearly, however, it will be somewhat delayed.
Knock-On Disruption In Nuremberg
While Nuremberg does not match its Bavarian neighbor at 
Munich Airport (MUC) for scale, it is still a key facility. As such, Corendon Airlines is far from the only carrier to have faced disruption as a result of the airport's temporary closure on Tuesday afternoon. On this front, Flightradar24 data at the time of writing showed that 35 of the airport's flights today had been delayed, with another three canceled.
The site uses a 'disruption index' of zero to five to illustrate an airport's overall delay picture, with Nuremberg's score at the time of writing being 3.4. A handful of services also had to divert to other airports as a result, such as Marabu flight DI6035 from Mallorca (PMI), which went to Stuttgart (STR). Elsewhere, a Corendon flight from Mallorca went to Munich and a Wizz flight from Cluj (CLJ) went to Memmingen (FMM), but, further afield, a Ryanair service from Girona (GRO) had to go to Prague (PRG).