| Title | Generation of spectra and stress histories for fatigue and damage tolerance analysis of fuselage repairs |
|---|---|
| Record ID | 36063 |
| Personal Name Creator |
Broek, D; Smith, S H; Rice, R C |
| Source | 56p. in various pagings |
| Corporate Creator | Battelle Memorial Institute. Columbus Laboratories; John A. Volpe National Transportation Systems Center (U.S.) |
| Publisher | United States. Department of Transportation. Federal Aviation Administration |
| Publication Date | 19911000 |
| Language | English |
| Abstract | This report describes a simplified procedure for the development of stress histories for use in the analysis of aircraft repairs.- Although repairs of all components of the airframe are of interest, this report concentrates on stress histories for fuselage skin repair, description of typical fuselage loadings is provided, and basic fuselage stress histories are described. A method for development of an exceedance diagram for analysis of fuselage skin repairs is detailed. Subsequently, a methodology for generating detailed stress histories is reviewed. Some of the key features are 1) the inclusion of a range of flights of different severities, 2) the inclusion of deterministic loads where they occur, e.g., ground-air-ground cycles, 3) the use of a near-optimum number of stress levels (10-16 positive and negative), 4) the combination of positive and negative excursions of equal frequency, and 5) matching of the total number of flights and cycles with the total exceedance diagram. Two methods of estimating fuselage skin stresses are presented, the first based on static equilibrium requirements and the second based on a limit load analysis. A comparison of the proposed history generation scheme with that of an airframe manufacturer for the KC-135 is also presented. The predicted fatigue crack growth patterns for a hypothetical through crack at a fastener hole are compared for the two history generation schemes at three areas within a fuselage. Predicted crack growth lives are within a factor of 1.5 for two of the three cases. For the third case (which is predicted to be the least severe by both techniques), the proposed scheme results in substantially longer crack growth life predictions. The probable reasons for these differences are discussed. |
| Rosap ID | dot:9085 |
| Rosap URL | https://rosap.ntl.bts.gov/view/dot/9085 |
| TRT Terms | Airframes; Airplanes; Fuselages; Maintenance |
| General Subjects | Fatigue; Maintenance and repair |
| Classification | NTL - AVIATION - AVIATION; NTL - AVIATION - Aviation Planning and Policy; NTL - AVIATION - Aviation Safety/Airworthiness |
| Geographical Coverage |
United States |
| OCLC | 227780376 |
| TRIS Online Accession No |
580058 |
| Contract Number | DTRS-57-89-C-00006 |
| Report Number | DOT-VNTSC-FAA-91-16 |
| Availability | Volpe National Transportation Systems Center, Technical Reference Center |
| Resource type | Tech Report |
| URL | https://ntlrepository.blob.core.windows.net/lib/36000/36000/36063/DOT-VNTSC-FAA-91-16.pdf |
| Format | |
| Database | NTL Digital Repository |