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Old 21st May 2008, 02:11
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ssg
 
Join Date: Dec 2003
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Some reading on rejected take offs....


The RTO maneuver has been a fact of a pilot’s life since the beginning of aviation. Each takeoff includes the possibility of an RTO and a subsequent series of problems resulting from the actions taken during the reject. Historically, the RTO maneuver occurs approximately once each 3,000 takeoffs. Because the industry now acknowledges that many RTOs are not reported, however, the actual number may be estimated at 1 in 2,000 takeoffs. For example, an unreported RTO may occur when a takeoff is stopped very early in the takeoff roll because the flight crew hears a takeoff warning horn, stops to reset trim, then taxis back to the runway and continues takeoff.

According to these statistics, a pilot who flies primarily long-haul routes, such as in our Boeing 747 fleet, may be faced with an RTO decision only once in 20 years. In contrast, a pilot in our DC-9 short-haul fleet who makes 30 takeoffs per month may see an RTO every 7 years. Unfortunately, the pilot in each of these fleets must be prepared to make an RTO decision during every takeoff.


Boeing studies indicate that approximately 75 percent of RTOs are initiated at speeds less than 80 kt and rarely result in an accident. About 2 percent occur at speeds in excess of 120 kt. The overruns and incidents that occur invariably stem from these high-speed events.

A takeoff may be rejected for a variety of reasons, including engine failure, activation of the takeoff warning horn, direction from air traffic control (ATC), blown tires, or system warnings. In contrast, the large number of takeoffs that continue successfully with indications of airplane system problems, such as master caution lights or blown tires, are rarely reported outside the airline’s own information system. These takeoffs may result in diversions or delays, but the landings are usually uneventful. In fact, in about 55 percent of RTOs the result might have been an uneventful landing if the take-off had been continued, as stated in the Takeoff Safety Training Aid published in 1992 with the endorsement of the U.S. Federal Aviation Administration (FAA).

Some of the lessons learned from studying RTO accidents and incidents include the following:


More than half the RTO accidents and incidents reported in the past 30 years were initiated from a speed in excess of V1.
About one-third were reported as occurring on runways that were wet or contaminated with snow or ice.
Only slightly more than one-fourth of the accidents and incidents actually involved any loss of engine thrust.
Nearly one-fourth of the accidents and incidents were the result of wheel or tire failures.
Approximately 80 percent of the overrun events were potentially avoidable by following appropriate operational practices.

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The Korean Air cargo jet which crashed near Stansted Airport had an engine on fire as it was taking off, eyewitnesses have told the BBC.

The jet crashed in a ball of flames in nearby fields, killing all four crew members.
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