PPRuNe Forums - View Single Post - The 80 knot call - potential for confusion?
Old 8th Oct 2003, 11:58
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Blacksheep
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Most of the above scenarios assume that an Air Data failure would be detected at 80 knots [i.e. low speed] or that an aircraft can safely be controlled in flight without airspeed data. Remember that altitude data may also be missing or corrupted. The last time I was involved in an incident involving a Pitot Static failure the PF identified the defect when he noted that the aircraft was well down the runway and going 'fast' yet he hadn't had an 80 knot call from the PNF. The pilot elected to continue the take-off, and in fact a rejected take off would have been much faster than 80 knots. [From examining the raw inertial groundspeed data later, about V1 in fact]. He made it back on the ground where the pitot head covers were found not to have been removed. On the aircraft type in question the static ports are seperate from the pitot probe but on other common rating types in the fleet the static sensors are on the probe and altitude data would also have been absent.

Don't discount the importance of a compromised Pitot Static system. The Air Data Computers supply data to so many other systems in current aircraft types that the total effect can be extremely confusing.

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Through difficulties to the cinema

PS. On another occasion I observed an aircraft taxi past and turn onto the runway with a pitot cover in place. When I phoned the tower I was scolded for wasting their time as the aircraft was "only positioning to the stand" That won't put me off doing the same thing again though!
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