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1. On 4 August 2009, aircraft CS-TKO “Diaspora” on flight S4 129 from Lisbon to Ponta Delgada, landed at the latter airport in an incident known as a “bounced landing”, meaning that the aircraft landed on its second touchdown on the ground.

2. Since this situation occurred with particularly intense contact between the aircraft and the ground, the captain requested an inspection of the aircraft by maintenance services in Ponta Delgada in order to assess potential abnorma l ities or damage due to the intense impact at the  time of landing. To this end, a set of data was used from a document, known as a “load report”, generated by the aircraft’s on-board computer.

3. This document included various figures referring to the intensity of the landing, namely 2.13 and 4.86. Of these figures, the first was considered the actual value reached by the aircraft during landing, while the second (which normally corresponds to visible damage) was considered completely unlikely, since no damage to the aircraft was detected.

4. An analysis of the data by the captain and maintenance services, together with an inspection of the aircraft as recommended by the manufacturer, revealed no evidence of damage or any other circumstances impeding it from flight or recommending that it be grounded. Having clarified the questions existing at the time, nothing was recorded in the technical log, a technical dispatch was performed on the aircraft, and the captain, following regular authoritative procedure, decided to make the return flight to Lisbon.

5. Upon arrival in Lisbon on 5 August, the captain, in accordance with standard procedures for any flight, notified Field Maintenance of the occurrence, and submitted the aforementioned “load report” including the figures stated above.

6. In Lisbon, a second inspection of the aircraft determined that it was in proper condition to fly, since no visible damage was found, and its flight performance had been completely normal . The aircraft performed its scheduled flights, LIS-PDL-OPO-LIS-FNC-LIS, returning to Lisbon that night. All of these flights were completely and objectively routine.

7. On the following day, 6 August, the aircraft entered the TAP hangar for a scheduled type A inspection, which includes a periodic, more comprehensive analysis of the aircraft’s condition. Since this inspection found minor damage to non-structural panels, the decision was made to perform a more in-depth analysis to verify all damage occurring in different systems. This resulted in sufficiently strong evidence that the figure of 4.86 corresponded to vertical acceleration values during the second touchdown of the landing in Ponta Delgada.

8. Based on this evidence which, once again, only appeared after the type A inspection, SATA notified the Aircraft Accident Prevention and Investigation Office (GPIAA), the National Institute of Civil Aeronautics (INAC) and Airbus of the occurrence.

9. To give an idea of the complexity of classifying a “severe hard landing”, Airbus was unable, until 10 August, to decode and conf i rm f rom di f ferent on-board systems that a “severe hard landing” had in fact occurred on 4 August.

10. This reaffirms SATA’s proactive and cautious approach, since it initiated legally established procedures with mere evidence, not actual confirmation.

11. Under the terms of the applicable legislation (Decree Law no. 238/2005 of 14 December) governing procedures for the mandatory reporting of accidents and incidents involving manned civil aircraft, the GPIAA and INAC were notified by those legally responsible for doing so, namely the captain of the aircraft in question and the Maintenance and Engineering Department, on 7 August, thus within the legally established time period (72 hours).

12. In addition to the notifications described above, SATA decided to request reports on the occurrence from the technical departments of Flight Operations and Maintenance and Engineering. In addition, a report was prepared by the Flight Safety Office.

13. On 7 August, as a preventive measure and by joint decision of the General Operations Manager, Flight Operations Department and Flight Safety Office, the technical crew involved in the incident was also relieved from duties until the conclusion of the internal investigation.

14. SATA is currently in possession of this technical information, which includes a factual analysis of the entire occurrence and several recommendations. The interim report of the GPIAA is also available on its website.

15. Under these circumstances, the Board of Directors is currently focusing on three essential questions:

1 – Why did a “severe hard landing” occur?

2 – Why was it not immediately confirmed, setting subsequent procedures in motion?

3 – What measures should be taken to avoid this type of occurrence?

As regards the first question, the following has been confirmed:

The main cause of the event involves a loss in the aircraft’s lift for a short duration of around 2’’, resulting in the activation of secondary system logic (in-flight deployment of ground spoilers), proven to be largely ineffective in these circumstances. Airbus, due to various incident reports of this type, changed the logic for the deployment of ground spoilers in A340 and A330 fleets (but not in the fleet of the A320 family, expected to be ready in mid-2010). To illustrate the degree of frequency of these events, Airbus had 19 similar occurrences in 2007 and 22 similar occurrences in 2008.

As regards the second question, we can verify the following:

The lack of visible damage or other evidence of a “hard landing” or “severe hard landing” made the confirmation of this fact particularly time-consuming and difficult. Not even Airbus was unable to confirm the occurrence of a “severe hard landing” until 10 August. Furthermore, “load reports”, as recognized by the GPIAA, likewise contain coded data that are difficult to decipher, and are not a mandatory requirement for this aircraft.

As regards the third question, the Board of Directors has decided that the recommendations from the various technical reports that it requested must be adopted in their entirety. We are therefore following the recommendations presented in the Flight Operations Department’s report, in line with the best practices supported by Airbus, namely:

• reinforce specialized theoretical and simulation training for all crews;

• amend the Technical Crew Training Manual to include content

reinforcing this specialized training.

Both of these measures have been submitted to the INAC, approved by the INAC and implemented as of this time.

The Board of Directors has decided that these technical recommendations must be adopted in their entirety.

The following recommendations from the Maintenance and Engineering Department's report have been adopted:

• reinforce the training programme on the decoding and interpretation of load report data for associated personnel and companies providing field maintenance services;

• review receipt and analysis procedures for reports from technical aircraft recording systems.

The Board of Directors has decided that these technical recommendations must be adopted in their entirety.

The following recommendations from the Flight Safety Office's report have been adopted:

• review procedure for recording suspected “hard landings”;

• reinforce training of crews for “bounced landings”, including the “go-around” (i.e. aborted landing) option;

• provide all A320 crews with the Flight Safety Office's presentation on the causes of “bounced landings” and different system logics. This presentation will also be available for consultation by all crew members at the Flight Operations Department portal;

• implement a crew recovery programme, which will take place by means of a joint technical opinion of the Flight Operations Department, Flight Safety Office and instructors.

The Board of Directors has decided that these technical recommendations must be adopted in their entirety.

The Board of Directors will follow the formal technical opinion of Airbus with regard to the airworthiness of the aircraft CS-TKO “Diaspora”. Consequently, and in other words, Airbus will be responsible for deciding when the aircraft meets all of the conditions to return to service in complete and total safety (anticipated before the end of this month). Following this, the aircraft’s Certificate of Airworthiness from the INAC will be eligible for revalidation.

In this way, the veracity of the information provided by SATA and the appropriate handling of this process have been duly proven (including via the report from the GPIAA), contrary to those who have attempted to use this incident to undermine SATA’s credibility, prestige and customer confidence.