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The U.S. Experience with Special Issuance Waivers
Introduction:
The special issuance (SI) waiver is the primary mechanism for U.S. pilots who do not meet FAA standards to obtain a medical certificate. About 34,000 pilots possess an SI waiver, but there is a large gap in knowledge of the relationship of SI waivers to aviation safety.
Methods:
All FAA pilot medical exams from 2002 through 2011 were matched to the National Transportation Safety Board accident database. The association of an SI waiver with accidents was explored using logistic regression models. Accident rates were also calculated using a novel technique based on pilots' reported flight times on their applications for medical certification.
Results:
For third-class flight exams overall, the presence of an SI waiver is associated with 8.7% lower odds of an accident than regular issuance exams. The calculated overall accident rate was 6.6 per 100,000 h. For the first and second-class exams, there was no significant association of SI waivers with safety for the overall group. The oldest and youngest pilots in the third-class group and the younger pilots in the first and second-class groups had somewhat elevated accident odds. The significance of these higher odds is uncertain, especially for the younger pilots who have a probable flight time bias.
Discussion:
The overall FAA program of special issuance waivers shows no detrimental effect on aviation accidents and enables a large number of pilots to safely continue their aviation pursuits in spite of failure to meet specific regulatory medical standards.Mills WD, Davis JT. The U.S. experience with special issuance waivers. Aerosp Med Hum Perform. 2018; 89(10):905-911.
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