By Viv Robins
The charter plane which crashed into the Red Sea shortly after leaving Egypt's Sharm el-Sheikh resort has focused attention on the record of the airliner involved - a Boeing 737.
A favourite of budget airlines, the short-haul jet is the best-selling commercial aircraft in aviation history.
Since the fleet was launched in 1967 it has put in about 124 million hours of service and travelled around 90 billion kilometres.
About 1,200 737s are in the air at any time and one takes off somewhere in the world every 5.3 seconds, often carrying holiday-makers aboard the growing number of low-cost airlines.
The British aviation expert David Learmount said the safety record of the Egyptian carrier involved in Saturday's crash, Flash Airlines, appeared to be good.
But he recalled that there had been other recent incidents involving 737s elsewhere on the continent.
"There were incidentally in Africa last year - in Algeria and Sudan - two 737s that crashed just after take-off, like this one did," Mr Learmount said.
Previous crashes have been attributed to rudder failure
"In those cases we have pretty good information now that they both involved engine failure - possibly something else as well, but at least engine failures."
There has also been a history of problems with the 737's rudder systems.
In October 2002 the Federal Aviation Administration in the United States ordered American carriers to replace them after rudder failure was blamed for crashes in Colorado in 1991 and Pennsylvania in 1994 in which a total of 157 people died.
The carriers were given six years to comply with the order and foreign carriers were expected to voluntarily follow suit.