Description

On 21 September 2012, a Bombardier Global Express (EC-JIL) being operated for private business purposes by Punto-FA on a passenger flight under callsign MGO 758 from Nice to Ibiza and a Dassault Falcon 2000 (CS-DNP) being operated by NetJets Europe on a passenger charter flight from Porto to Ibiza under callsign 559U came into conflict in Class 'A' airspace near Ibiza Airport in night Visual Meteorological Conditions (VMC) as both aircraft were positioning to final approach.

Investigation

An Investigation was carried out by the Spanish Civil Aviation Accident and Incident Investigation Commission (CIAIAC).

It was noted that both aircraft crews were experienced on aircraft type and that the pilots of the Spanish-registered aircraft were of Spanish nationality and those of the Portuguese-registered aircraft were of Dutch nationality. These crews had, respectively, Level 5 and Level 6 English Language Proficiency endorsed on their licences.

It was dark at the time of the conflict and the prevailing weather conditions recorded at Ibiza Airport shortly before it occurred included visibility >10km and the only cloud SCT/4500 feet aal.

It was established that the Global Express aircraft had been in radio and radar contact with the Palma ACC which provides Ibiza APP service and was being vectored towards the runway 06 LOC at Ibiza on a heading of 240° in descent to FL 080 to the southeast of Ibiza. The Falcon aircraft was approaching Ibiza from the north west on a direct track to TILNO IAF for the same Instrument Landing System (ILS) approach at Ibiza. It was initially under the control of the Levante TACC and was then transferred to Ibiza APP and cleared to continue descent to FL 090 and subsequently re-cleared to 2500 feet Altimeter Pressure Settings.

Ibiza APP then re-cleared the Global Express to descend to 2500 feet QNH and, just over a minute later, instructed the Falcon to reduce speed to 250KIAS and re-cleared it to descend to 3000 feet QNH. Just over one minute after this, the Falcon reached TILNO, which is not on the ILS LOC track but to the north of it, and turned left towards the LOC and the crew requested clearance to descend on the ILS. In response, APP instructed the aircraft to turn right onto radar heading 160° and cross the LOC. After "several requests to confirm the instruction to cross the LOC", APP instructed the aircraft to "turn immediately onto heading 180°" and the crew started this turn when their aircraft was just reaching the LOC. They requested the intentions of APP but "the controller did not reply".

Almost immediately, APP instructed the Global Express, which had previously been instructed to turn right onto radar heading 270°, to turn further right onto heading 030° to intercept the 06 LOC and cleared it for the ILS approach. This instruction was given using English to communicate with this aircraft for the first time. It was not acknowledged.

APP then repeated the instruction to the Falcon to turn immediately onto heading 180°, after which the aircraft reported a TCAS RA. Two seconds, later, Ibiza TWR called APP to report that the two aircraft were both at around 3,000 ft. Shortly afterwards, the Global Express called APP to advise that it had also received a TCAS RA and that it was turning to heading 020° to intercept and complete the ILS approach to runway 06.

The diagram below shows the tracks flown by the two aircraft during the encounter.

It was subsequently established that:

• the Global Express had received a TCAS RA to descend and the Falcon a TCAS RA to climb and both had been followed.

• the CPA was 1.2nm horizontally when at 300 feet vertical separation. At that time, the Global Express was descending through 2700 feet QNH on heading 270° and the Falcon was in the right turn to heading 160° at 3000 feet QNH.

• Five seconds after the CPA, the Global Express was turning right and descending through 2600 feet QNH and the Falcon was climbing through 3100 feet QNH.

It appeared that the Falcon RA annunciation may have preceded that received by the Global Express.

A number of pertinent facts were established, including the following:

• the airspace where the conflict occurred was notified as Class 'A'.

• conversations between Ibiza APP and the Falcon aircraft all took place in English, whilst those with the Global Express took place in Spanish except for one use of English by the controller during the conflict.

• the published RNAV STAR applicable to the Falcon aircraft was a VARUT 1V, the Jeppesen Plate for which was carried on board and was found to contain an explicit warning not to proceed beyond the IAF without ATC clearance.

• The IAF for the 06 ILS at Ibiza is to the north of the LOC rather than on it, and the ILS chart shows a 5.3nm leg on 088°M from there to the IF which is on the LOC at 12.7nm from touchdown.

• the APP controller noted that on the day of the incident he had been responsible for both the Ibiza route and Ibiza approach sectors so that his radar display was "not ideally suited to work the approach since said display was too broad and distorted the view of the approach".

• The LoA between Ibiza APP (provided by Palma ACC) and Ibiza TWR states that "the separation between successive aircraft in VMC shall be 8 nm, this separation to be established as soon as the first aircraft reaches the boundary of the Ibiza ATZ" (5nm). It also states that "Ibiza APP will transfer aircraft to Ibiza TWR between 15 and 6 NM out on final or coordinate the transfer on a segment of the circuit".

• In the absence of any awareness of other traffic, the Falcon crew were confused when the APP controller instructed them to cross the LOC without providing any explanation.

• Once separation had been lost, Ibiza APP did not provide essential traffic information to either of the aircraft to assist their crews in maintaining their own separation in VMC. It was noted that such action is a requirement of the Spanish Air Traffic Regulations.

The formally-recorded Conclusions of the Investigation included the following:

• The aircraft with registration CS-DNP went past the IAF TILNO without receiving clearance from Ibiza APP to do so.

• Ibiza APP only realised that aircraft CS-DNP had gone past the IAF when the crew of the aircraft called requesting clearance to follow the runway 06 ILS localiser.

• The subsequent instructions by Ibiza APP to aircraft CS-DNP required a series of explanatory messages due to the lack of situational awareness on the part of the crew of the aircraft.

• Ibiza APP did not explain to aircraft CS-DNP the reasons for its instruction to cross the 06 ILS localiser.

• The communications between Ibiza APP and aircraft EC-JIL were held in Spanish.

• Neither aircraft was cleared to altitudes that ensured the minimum vertical radar separation of 1,000 ft, a separation that fell to under 500 ft by the time the aircraft reached their cleared altitudes (3,000 ft and 2,500 ft).

The Investigation determined that the Cause of the conflict was aircraft CS-DNP crossing the IAF TILNO without the relevant clearance due to not having a clear picture of the approach sequence.

It was additionally determined that Contributory Factors were:

• the failure of Ibiza APP to indicate the reason for its instructions
• the communication between Ibiza APP and aircraft EC-JIL was conducted in Spanish.

One Safety Recommendation was made as a result of the Investigation as follows:

• that the Spanish Aviation Safety and Security Agency (AESA) promote the implementation of appropriate actions to minimise the problems caused by the use of the Spanish language (for ATC communications) in situations involving crews that do not understand that language.

It was noted that this Recommendation was essentially a repeat of a similar one made in 2003 "regarding the exclusive use of English in communications".

The Final Report was approved on 27 February 2014 and subsequently made available in English translation.

Further Reading

• Loss of Separation
• Collision Avoidance
• Loss of Separation - ATCO-induced Situations
• ATCO Actions in Case of Loss of Separation
• ACAS Resolution and Traffic Advisories
• TCAS Occurrence (OGHFA SE)
• Traffic Information
• ACAS: Guidance for Controllers
• Situational Awareness
• European Action Plan for Air Ground Communications Safety
• Language
• Work in progress:English Language Proficiency Requirements