1、Lessons Learned Entry: 0360Lesson Info:a71 Lesson Number: 0360a71 Lesson Date: 1995-10-11a71 Submitting Organization: HQa71 Submitted by: Pete RutledgeSubject: Single-string Pitot-static Air Data in Inherently Unstable Aircraft Description of Driving Event: The X-31 is an inherently unstable experim
2、ental aircraft. Its dynamic stability is dependent on air data from the Pitot-static system. Unexpected icing of the single-string unheated Pitot-static air data source resulted in the aircraft departing controlled flight and crashing.Photo of the x-31 jet in flightX-31 Experimental AircraftLesson(s
3、) Learned: The loss of air data from a single-string Pitot-static source due to icing or foreign object damage, can result in a departure from controlled flight (and possible catastrophic loss of aircraft) in aircraft which are inherently unstable and dependent on air data for dynamic stability.Reco
4、mmendation(s): Consider the use of a redundant air data source (one of diverse design so as to lessen the probability of common cause failure) to increase the reliability of air data.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Evidence of Recurre
5、nce Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Aircrafta71 Flight Equipmenta71 Safety & Mission AssuranceAdditional Info: Approval Info: a71 Approval Date: 1995-10-12a71 Approval Name: Pete Rutledgea71 Approval Organization: QSa71 Approval Phone Number: 202-358-0579Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
