In a final report on Swiss flight LX18 on July 11, 2023, which had to turn back to Paris due to an unusual odor, the Swiss Aircraft Accident Investigation Board (SAI) found serious deficiencies in the handling of smoke hoods (Personal Breathing Equipment, PBE).
Investigators are criticizing not only the design of a problematic PBE model, but also the approval process and training methods of Swiss. Particular attention is being paid to the tragic death of a flight attendant following an A220 emergency landing in Graz on December 23, 2024, in which the same PBE model was allegedly used. Switzerland has since taken over the investigation into this incident, Flight LX1885, from Austria to examine a possible connection with the use of the criticized smoke hoods.
The incident on Flight LX18 and the pitfalls of smoke hoods
On July 11, 2023, Swiss Flight LX18 was scheduled to fly from Zurich to Newark on an Airbus A330-300. However, over the airspace of the English Channel, an "unusual odor" was detected on board, forcing the pilot to return to Zurich. Due to the weather conditions, the aircraft eventually landed at Paris-Charles de Gaulle. The final report now available from the Swiss Air Accident Investigation Authority (SUST), whose publication was first reported by the "aeroTelegraph" portal, analyzes the incident in detail and sheds light on the role of the smoke hoods used.
The investigators focused in particular on models of so-called Personal Breathing Equipment (PBE), which are available for emergencies to protect the airways of cabin crew from smoke and toxic fumes. Handling the PBE model in question caused "significant difficulties" for several flight attendants, the Sust found. These problems became apparent both during "unpacking, unfolding, setting up, and activating the devices" and during subsequent use. For example, one flight attendant needed three minutes to activate the PBE, which can mean a critical delay in an emergency situation. Some flight attendants also reported that breathing with the PBE in place, especially exhaling, proved to be "very difficult." The front window of one of the canopies examined was even cracked.
To objectively assess the identified deficiencies, the Swiss Federal Institute for Standardization (SUST) simulated the use of the smoke protection hoods with trained flight attendants. Compared to another model considered unproblematic, the participants needed an average of 19 seconds to unpack, pull up, and activate the criticized hoods, but in some cases, it took up to 42 seconds longer. On average, the testers handled the PBE model used in Swiss's A330 in 78 seconds, compared to 59 seconds with the comparison model. However, according to current certification standards, such hoods should be unpacked and activated within 15 seconds, which highlights the serious deviations.
Criticism of Swiss's approval procedures and internal training
The results of the Sust investigation lead to twofold criticism: firstly, of the approval process for PBE models in general, and secondly, of Swiss's training methods. The investigators state: "It is difficult to understand how two common PBE models were eligible for approval despite having such obvious deficiencies." This suggests "that the approval process for PBEs contains fundamental deficiencies that have not been recognized until now." They call for the European Aviation Safety Agency (EASA), which is responsible for certifying aviation products in Europe, to review its testing procedures for such safety equipment. Manufacturers of PBE systems must ensure that their products function quickly and reliably not only under laboratory conditions, but also under stress and in real emergency situations.
But Swiss, a subsidiary of the German airline Lufthansa, also faces serious criticism. The report states: "The crew members' training was carried out exclusively with dummy PBEs provided for training purposes, which differ significantly from the real PBEs used in an emergency." This resulted in the crew members remaining unaware of "various difficulties in using the PBE." Such an approach, in which training materials do not reflect reality, can significantly impair the readiness and effectiveness of cabin crew in critical situations. The Swiss authorities require airlines to ensure that their crews are optimally prepared for emergencies, which requires realistic training with the equipment actually used.
Tragic death after flight LX1885: Investigations in Switzerland
The explosive nature of these findings is heightened by another, even more serious incident. Swiss has since removed the PBE model in question, which was criticized in the Sust report, from its aircraft. However, it was reportedly in use before an A220 emergency landing on December 23, 2024, in Graz, Austria. Tragically, a 23-year-old Swiss flight attendant died in a hospital following this incident. The exact cause of his death is under investigation. Switzerland recently took over the investigation into flight LX1885, also operated by Swiss, from the Austrian authorities to examine a possible connection with the allegedly problematic smoke hood.
This case highlights the importance of safety equipment and adequate training for flight crew. The investigation will need to clarify whether there is a direct causality between the use of the PBE model and the tragic outcome of the incident. Such investigations are complex and require a detailed analysis of all factors involved, from the technical function of the equipment and the specific circumstances of the incident to the airline's internal procedures and training programs. The results of this investigation will not only be of great importance to Swiss, but could also have far-reaching consequences for certification procedures and training standards throughout international aviation to ensure the safety of flight crew in emergency situations. Regulatory authorities such as EASA and ICAO are closely monitoring these developments in order to make adjustments to international standards and recommendations if necessary.
and 