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An air turnback is a situation where an aircraft returns to land at the departure aerodrome without having initially planned to do so.
The most common reason for air turnback is an emergency or abnormal situation during or shortly after take-off, the most common being engine failure. If the problem happens during acceleration, the crew might attempt to reject the take off depending on the speed and the nature of emergency. Sometimes a safer option is to get airborne and then make an approach and land. A probable complication in this case is that the aircraft's current weight may be greater than the certified maximum landing weight (MLW). If the crew opts for a turnback in this case, there are three options:
- Make an overweight landing. The pilot in command has the right to deviate from prescribed procedures as required in an emergency situation in the interest of safety, i.e. they may choose to land even though the aircraft is heavier than the MLW if they consider this to be the safest course of action. The landing will be more challenging and require longer runway, thus increasing the chance of a runway excursion. Also, a special post-landing inspection will have to be carried out.
- Burning the excess fuel, e.g. by entering a holding pattern. This is a safe option in many cases but if it is considered that by the time the weight is reduced below the MLW the aircraft will no longer be airworthy, or there is another urgent matter (e.g. a medical emergency) another course of action will be taken.
- Dump fuel. This option is not available for most aircraft types and even if it is, the respective system may not have been installed on the particular aircraft. Additional restrictions may also apply, e.g. a minimum level to perform the operation or the need to reach a dedicated fuel dumping area.
Air turnback may happen during all phases of the flight, e.g. climb, cruise or even when the aircraft has reached the vicinity of the destination aerodrome (but is unable to land due to weather conditions). Any significant problem with the aircraft during the climb phase is likely to result in a turnback because of the closeness of the departure aerodrome. During the cruise, if an engine fails (or annother emergency situation arises, e.g. loss of cabin pressure), the flight crew will evaluate the situation and decide on the further course of action. Depending on the circumstances (severity of the situation, available fuel, company policy, weather, etc.), the choice may be to continue to the planned destination, to divert to the planned alternate, to land at the nearest suitable aerodrome or to return to the point of departure.
Accidents and Incidents
- A320, Auckland New Zealand, 2017 (On 27 October 2017, an Airbus A320 returned to Auckland after advice from ATC that the right engine may have been affected by ingestion of FOD during engine start - a clipboard and paper left just inside the right hand engine by an employee of the airline’s ground handling contractor acting as the aircraft loading supervisor. The subsequent inspection found paper throughout the engine and minor damage to an engine fan blade and the fan case attrition liner. The Dispatcher overseeing the departure said she had seen the clipboard inside the engine but assumed it would be retrieved before departure.)
- B773, Singapore, 2016 (On 27 June 2016, a Boeing 777-300ER powered by GE90-115B engines returned to Singapore when what was initially identified as a suspected right engine oil quantity indication problem evidenced other abnormal symptoms relating to the same engine. The engine caught fire on landing. The substantial fire was quickly contained and an emergency evacuation was not performed. The cause of the low oil quantity indication and the fire was a failure of the right engine Main Fuel Oil Heat Exchanger which had resulted in lubrication of the whole of the affected engine by a mix of jet fuel and oil.)
- A320, en-route, east of Cork Ireland, 2017 (On 2 November 2017, the flight crew of an Airbus A320 climbing out of Cork detected a “strong and persistent” burning smell and after declaring a MAYDAY returned to Cork where confusing instructions from the crew resulted in a combination of the intended precautionary rapid disembarkation and an emergency evacuation using escape slides. The Investigation highlighted the necessity of clear and unambiguous communications with passengers which distinguish these two options and in particular noted the limitations in currently mandated pre flight briefings for passengers seated at over wing emergency exits.)
- MA60, en route, west of Bima Indonesia, 2011 (On 12 December 2011, the crew of a Xian MA60 delayed their response to an engine fire warning until the existence of a fire had been confirmed by visual inspection and then failed to follow the memory engine shutdown drill properly so that fire continued for considerably longer than it should have. The Investigation found that an improperly tightened fuel line coupling which had been getting slowly but progressively worse during earlier flights had caused the fire. It was also concluded that the pilots' delay in responding to the fire had prolonged risk exposure and "jeopardised the safety of the flight".)
- DH8C, vicinity Abu Dhabi UAE, 2012 (On 9 September 2012, the crew of a DHC8-300 climbing out of Abu Dhabi declared a PAN and returned after visual evidence of the right engine overheating were seen from the passenger cabin. The Investigation found that the observed signs of engine distress were due to hot gas exiting through the cavity left by non-replacement of one of the two sets of igniters on the engine after a pressure wash carried out overnight prior to the flight and that the left engine was similarly affected. The context for the error was identified as a dysfunctional maintenance organisation at the Operator.)
- B38M, en-route, northeast of Jakarta Indonesia, 2018 (On 29 October 2018, a Lion Air Boeing 737-MAX 8 crew had difficulty controlling the pitch of their aircraft after takeoff from Jakarta and after eventually losing control, a high speed sea impact followed. The Investigation found that similar problems had also affected the aircraft’s previous flight following installation of a faulty angle-of-attack sensor and after an incomplete post-flight defect entry, rectification had not occurred. Loss of control occurred because the faulty sensor was the only data feed to an undisclosed automatic pitch down system, MCAS, which had been installed on the 737-MAX variant without recognition of its potential implications.)
- Decision Making
- Decision-Making (OGHFA BN)
- Fuel Dumping: Guidance for Flight Crews
- Fuel Dumping - Guidance for Controllers
- Engine Failure: Guidance for Controllers
- Engine Failure After TakeOff - Light Twin Engine Aircraft