What is Helios Airways Flight 522?
{{Infobox aircraft occurrence | occurrence_type = Accident | name = Helios Airways Flight 522 | image = Helios Airways Boeing 737-300 5B-DBY PRG 2005-3-31.png | alt = | caption = 5B-DBY, the Boeing 737-31S involved in the accident | date = {{start-date|14 August 2005}} | type = Crashed following crew incapacitation due to [[Uncontrolled decompression|loss of pressurization]] | site = [[Grammatiko]], [[Marathon, Greece]] | coordinates = {{coord|38|13.894|N|23|58.214|E|type:event|display =inline,title}} | occupants = 121 | passengers = 115 | crew = 6 | fatalities = 121 | survivors = 0 | aircraft_type = [[Boeing 737-300|Boeing 737-31S]] | aircraft_name = ''[[Olympia, Greece|Olympia]]'' | tail_number = 5B-DBY | operator = [[Helios Airways]] | origin = [[Larnaca International Airport]], [[Larnaca]], Cyprus | stopover = [[Athens International Airport]], Greece | destination = [[Prague Václav Havel Airport|Prague Ruzyně Int'l Airport]], Prague, Czech Republic | IATA = ZU522 | ICAO = HCY522 | callsign = HELIOS 522 }} On August 14, 2005, '''Helios Airways Flight 522''' covered the route between Larnaca International Airport (Cyprus), and Ruzyně International Airport (Prague, [[Czech Republic]]), with a stopover in Athens ([[Greece]]). The aircraft, a [[Boeing 737]], crashed on a mountain at 09:04 UTC on that day, near Grammatiko, 40 km north of [[Athens]] while on approach to Athens airport capital, killing all 115 passengers and 6 crew members on board.<ref>{{cite web|last=Ranter|first=Harro|title=ASN Aircraft accident Boeing 737-31S 5B-DBY Grammatikos|url=https://aviation-safety.net/database/record.php?id=20050814-0|url-status=live|archive-url=https://web.archive.org/web/20220408191106/https://aviation-safety.net/database/record.php?id=20050814-0|archive-date=April 8, 2022|access-date=May 11, 2022|website=aviation-safety.net|publisher=[[Aviation S