The objective of this paper is to analyze an important aspect of the safety posture of airlines during the years following deregulation using service difficulty reports (SDRs). Safety posture is measured by the incidence of serious aircraft service difficulties that can be taken as an indication of the potential for safety failures. SDRs report aircraft problems encountered while in operation. They vary in severity from the mundane to the serious. Despite the weaknesses stemming from potentially poor reporting, SDRs can be taken as one indicator of the effectiveness of an airline's maintenance program and can therefore shed some light on safety posture. In explaining safety posture, variables used are an airline's maintenance expenditures, aircraft fleet composition and age, and scale of operation. We also differentiate between carriers established before airline deregulation and new entrants. With the help of statistical analysis on data for the period 1980-1984, we look at some of the evidence on airlne safety posture as defined. The consistent evidence we have suggests that safety posture, as indicated by SDRs, is associated with the scale of operations--the rate of serious SDRs per block hour is likely to increase with exposure (stage length) and decrease with the number of departures. The rate of serious SDRs per departure is likely to decrease with number of block hours of operations. The aging of aircraft, with respect to SDRs, is significantly different for different aircraft size groups--large wide-bodied aircraft appear to have a sharper increase in the incidence of SDRs with age than do the smaller narrow-bodied aircraft. Further, there is also consistent evidence that the incidence of SDRs is not any higher for the new entrants than it is for the established carriers.

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 43-51
  • Monograph Title: Modeling and Analysis of Airport and Aircraft Operations
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00494442
  • Record Type: Publication
  • ISBN: 0309048176
  • Files: TRIS, TRB
  • Created Date: May 31 1990 12:00AM