Ryanair atterra in emergenza con 220 kg di carburante

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Visto l'articolo di Leonard, ieri è stato pubblicato il report dell'AAIB sull'indagine.
https://assets.publishing.service.g...e2435f202eeee/Boeing_737-800_9H-QBD_10-26.pdf
Punti che mi sono sembrati salienti:

Pre-flight planning

Pre-flight preparations and planning were conducted by each pilot at home prior to the flight. The crew had been informed of the potential disruption due to storm Amy through two communications sent the day before and on the morning of the flight. Extra contingency fuel was carried due to the forecast wind at the destination but the amount of additional fuel was limited by the expectation that an approach to the shorter runway at Prestwick would be required. The additional fuel allowed for about one hour of extra endurance at cruise speed.​

ATC Flight Plan
The operator’s Operations Manual did not require the pilots to inform the operations centre that they were changing the commercial alternate to Manchester. Consequently, the destination alternate on the flight plan remained as Glasgow. The pilots reported that changing a destination alternate would require a telephone call to the operations centre and the OFP to be re-issued, which could take up to 15 minutes. However, as they had the required fuel, routing and level information this was not necessary. All flight plan information is available to ATC, but during a flight any abnormal events are driven by the pilot’s intentions. This requires clear communication between the pilot and ATC, who will coordinate any requests. Alternate airfields are not sent a copy of the flight plan and so any diversion request must be coordinated through ATC; nominating an airfield as an alternate on a flight plan does not ensure acceptance.​

Decision-making and emergency handling

[...]
After the second go-around at Prestwick, the crew asked to divert to Manchester because of the operator’s policy that a third approach is not permitted following two windshear escape manoeuvres, but the request was refused. Although the reason for the refusal was not established, it appeared to have resulted from a breakdown in communication between units within Manchester Airport. According to the airport and handling agent’s policies, the diversion request should have been accepted. The pilots believed that their fuel state did not permit them to declare a fuel emergency, which would have allowed them to go to Manchester. The operator commented that an emergency could have been declared if the crew was concerned that landing at Edinburgh would not have been assured because of
windshear. However, the crew based their decision to divert to Edinburgh on a weather report that did not include windshear (although it did report some previous go-arounds) and because Glasgow Airport, although nearer, was experiencing similar weather conditions to Prestwick.

[...]
Another approach at Edinburgh would have protected final reserve fuel – if it had resulted in a safe landing – but the crew was concerned that if it resulted in another missed approach, they would then be committed to making a third approach in windshear conditions with no option other than to fly through a windshear warning to land.

Prior to declaring the fuel emergency, the pilots had calculated and agreed that they would arrive at Manchester with between 500 and 700 kg of fuel. When they programmed the FMS, however, it predicted arriving at Manchester with 300 kg. Both calculations were below the final reserve fuel of 1,100 kg. The operator’s final reserve fuel policy aims to ensure a safe landing when unforeseen circumstances do not permit the flight to be conducted safely as originally planned, and it is likely that three windshear escape manoeuvres and a diversion would be captured by this definition. The policy also requires commanders to consider ‘a safe landing option’ that preserves final reserve fuel before exploring ‘any landing option’. The commander considered that if they remained at Edinburgh it could lead to them making an approach with no option other than to fly through any windshear warning to land. In the circumstances, the commander considered a diversion to Manchester to be the safest option even though it would inevitably lead to landing below final reserve fuel.

When the low fuel quantity tank 1 message was displayed, there was an opportunity to review the decision to divert because Edinburgh, although behind them, was closer than Manchester. In the event, the aircraft continued to Manchester where it landed safely, but it is unlikely that there would have been sufficient fuel available for another go-around. The crew had considered Manchester to be their preferred alternate airport from the outset and it is possible that this influenced their decision-making.​

Diversion request
In the UK AIP, Manchester Airport regulations state, ‘All operators are advised that before planning Manchester as an alternate, they are required to have ground handling available at the airport’. Manchester is a regular destination of the operator of 9H-QBD and so ground handling was available.

At 1822 hrs, the pilot notified Prestwick ATC that their intention was to divert to Manchester in the event of a go-around from the second approach. At 1829 hrs Manchester ATC received the request and called Airfield Control for a decision.

At 1834 hrs, Airfield Control called ATC stating the handling agent was unable to accept the diversion. Prestwick were told the diversion could not be accepted, but the reason of a lack of handling capacity was not passed. The refusal was subsequently relayed to the pilots at 1837 hrs, after the second missed approach. The Manchester Airport Excess Parking Plan was not in force on the day, although they had accepted 19 diversions due to Storm Amy. The handling agent for the operator stated it was their policy to accept diverting aircraft from this operator, but there was no record of the communications between Airfield Control and the handling agent. Therefore, it was not established how the decision was made to refuse the diversion. Following this incident Manchester Airport reviewed its procedures and restated that diversions will be accepted by Airfield Control if there is parking space available. Handling agents would be notified but would not be involved in the decision-making process. Manchester reiterated that to use Manchester as an alternative airport an operator must have a handling agent.

[...]During the routing to the hold, ATC stated that Manchester was unable to accept their diversion request, but no explanation was given as to why the request had been refused. The pilots obtained the weather for Edinburgh Airport via ATC which reported strong winds but no windshear, although there had been some aircraft go-arounds earlier. The nearest alternative airport was Glasgow Airport, which was reporting in the ATIS that aircraft had experienced windshear on finals. Based on this information the pilots requested a diversion to Edinburgh, this request was made six minutes after they were told by ATC that Manchester had refused to accept the diversion. It took a further five minutes for their request to divert to Edinburgh to be accepted. During that time the pilots discussed declaring a “fuel minimum” or a “mayday” to go to Manchester.
However, they agreed that their current fuel state did not meet the criteria written in the company operations manual to declare an emergency. They discussed their concern that they might receive a windshear warning at Edinburgh, and they also discussed the windshear warnings, wondering whether they had been spurious.[...]​

Insomma, pare che i veri colpevoli siano stati i controllori del traffico dell'aeroporto di MAN: dato che hanno negato la diversion, dicendo che l'handling agent non era in grado di accettarli. Eppure, non c'è stata alcuna comunicazione fra l'ATC e l'handling agent!
È anche vero, che lo stesso giorno, MAN ha gestito altre 19 diversion, quindi forse l'operatore si è confuso?

Tra l'altro, anche l'ATC di PIK poteva essere più dettagliato e cautelativo quando ha comunicato le condizioni meteo a EDI (c'erano stati altri go-around), non è che ci fosse meteo sereno, anche perché Glasgow non è che sia così lontano da Edinburgh .


In ogni caso, fortunatamente, alla fine tutto è andato per il verso giusto.