Obviously inspired by the current 737 Max situation, what is the longest period of time that any individual type of airliner has been grounded for safety concerns (excluding those that never returned to service)?
What is the longest period of time an aircraft type has been grounded due to safety concerns?
6$\begingroup$ I think that the de Havilland Comet was permanently removed from service after catastrophic pressurization failures. en.wikipedia.org/wiki/De_Havilland_Comet $\endgroup$– JScarryMar 13, 2019 at 22:57
5$\begingroup$ @JScarry: Not quite - several military Comet 1s were rebuilt with stronger fuselages and returned to service (although none of the commercial ones), and the Comet returned to commercial passenger service in 1958 with the Comet 4, which had the bad luck that the bigger, more capable 707 entered service just a few weeks later. $\endgroup$– VikkiMar 13, 2019 at 23:00
$\begingroup$ @Sean If you rebuild them, does it count as the same aircraft :) $\endgroup$– JScarryMar 13, 2019 at 23:05
2$\begingroup$ @JScarry: According to the regulators, it does. $\endgroup$– VikkiMar 13, 2019 at 23:07
3$\begingroup$ Possibly of interest: news.aviation-safety.net/2019/03/14/… $\endgroup$– zenzelezzMar 15, 2019 at 7:09
The Yak-42 was grounded from June 1982 to October 1984 (26 months) for a cause similar to Alaska Airlines Flight 261.
After the crash of Air France 4590 (July 2000), the Concorde was grounded until November 2001 (same link) - 16 months.
The Yak-42 was grounded for roughly 2 years due to stabiliser malfunction.
The de Havilland Comet was grounded for OVER 4 Years (Aug 1954 - Sept 1958) because of blown out windows, causing decompression and in-flight disintegration.
Space Shuttle was grounded after Columbia crash from 2003 February till July 4, 2006 with only single test mission over this time in 2005.
Columbia crashed while flying at Mach 19.5 (23,278 Km/hr; 14,464 Mph), at 209,800 feet altitude (63.9 km; 39.73 mi). It is probably possible to argue that at the time of crash it was flying as an aircraft (glider), interacting heavily with the air, and it disintegrated because of aerodynamic forces.
1$\begingroup$ Ah, but I did specifically say airliner in the body of the question. Still worth including of course $\endgroup$– llamaNov 20, 2020 at 21:20
1$\begingroup$ Depends on the definition of the airliner. If just "intended for carrying multiple passengers or cargo in commercial service" as Wikipedia says, Shuttle might qualify. It is at least quite big and expensive. $\endgroup$– h22Nov 20, 2020 at 22:09
The Space Shuttle was grounded for 36 months following the Challenger disaster and again for 29 months after the loss of Columbia.
Whether that qualifies as an aircraft or as a falling brick is debatable, though.
The Boeing 787 was grounded from January 17, 2013 to April 26, 2013 due to lithium ion battery problems. I think this may be the longest a commercial airliner has been grounded but I am not sure if there is a military plane that was grounded for longer.
7$\begingroup$ technically it wasn't grounded. The AD stated it was required to undergo specific modifications before being allowed to fly, modifications which weren't available at the time. But there was no AD forbidding the operation of the aircraft. $\endgroup$– jwentingMar 14, 2019 at 5:05