A memo to Ryanair pilots has threatened them with the sack if they fail to obey safety rules on landing.
Ryanair jets were involved in three incidents in two years
It follows reports of three incidents of dangerous approaches to airports by Ryanair jets in a two-year period.
In one case a plane flew low over rooftops near Cork airport in Ireland, causing a cockpit alarm to sound.
The memo, from Ryanair chief executive Michael O'Leary, tells pilots they will be demoted after the first incident, and sacked after a second.
A copy of the memo, dated 25 September 25 2006, has been obtained by The Times. It states that a new disciplinary procedure is being introduced in response to a series of "high-energy approach incidents over the past two years".
It continues: "Any event involving any of our aircraft passing the 500ft landing-gate incorrectly configured or at excessive speed, and which does not perform a go-around, will automatically lead to both crew members being demoted in the case of their first transgression of this policy."
The warning follows three cases of Ryanair jets approaching an airport too fast or at the wrong height and being forced to abort landing.
In the latest incident to emerge, an aircraft approaching Cork airport flew so low that it triggered two warnings in the cockpit and sparked 16 complaints from residents.
All Ryanair staff are under pressure to meet turnaround times of only 25 minutes - the tightest in the industry - and pilots' unions say this can lead to mistakes.
A Ryanair spokeswoman said: "This memo underlines the commitment of Ryanair and its pilots to passenger safety.
"Our safety instruction to all pilots is, if in doubt you must perform a go-around, and we expect all of our pilots to follow this safety guidance at all times."
She said that in the two-year period in which the incidents occurred, Ryanair operated over 500,000 flights.