- Author
-
Beeson, H. D.
|
Heinonen, E. W.
|
Luehr, C.
|
Allred, R. E.
|
Kent, L. A.
|
Gill, W.
- Title
- Aircraft Composite Material Fire Damage Assessment. Volume 1. Discussion. Final Report. August 1989-September 1990.
- Coporate
- New Mexico Univ., Albuquerque
- Sponsor
- Air Force Engineering and Services Center, Tyndall AFB, FL
- Report
-
NMERI-IP-2.22(2); YE-TR-90-02, VOL 1 OF 2,
September 1990,
159 p.
- Distribution
- Available from National Technical Information Service
- Contract
- F29601-C-87-0001
- Keywords
-
composite materials
|
fire damage
|
carbon
|
aircraft fires
|
aircraft fuels
|
epoxy resins
- Identifiers
- fire damage assessment
- Abstract
- Samples of carbon/epoxy aircraft skin material were exposed to fuel fires to investigate the length of time before they experienced significant damage due to external heating from the fire. Samples were removed from the fire at pre-determined times and destructively tested to compare loss in material strength to nonexposed baseline samples. The effects of cooling the samples with fire fighting foam and of placing samples under stress to simulate aircraft static loading were investigated. Additionally, a limited number of samples were fatigued to failure following fire exposure to examine long-term effects. Significant damage was measured between 17 and 20 seconds after fire ignition at a height of six feet. The loss of strength was approximately 5% for exposure times of between 17 and 20 seconds, 10% for exposure times between 27 and 30 seconds, and 20% for exposure times between 37 and 40 seconds, regardless of the test configuration. Significantly, no thermal shock effects resulting from cooling by the foam were observed. Fire ignition and buildup behavior were analyzed to correlate with observed material damage. A one dimensional material model to calculate in-depth material temperatures was developed and verified. Results from this testing were correlated to the design and operational requirements of a fire protection system to protect composite skinned aircraft.