Particulate-phase exhaust properties from two different types of ground-based jet aircraft engines--high-thrust and turboshaft--were studied with real-time instruments on a portable pallet and additional time-integrated sampling devices. The real-time instruments successfully characterized rapidly changing particulate mass, light absorption, and polycyclic aromatic hydrocarbon (PAH) content. Th...

A recent strategy carried out by the aircraft industry to reduce the total cost of the new generation fighters has consisted in the development of a single airframe with different technical and operational specifications. This strategy has been designed to reduce costs in the Research, Design and Development phase with the ultimate objective of reducing the final unit price per aircraft. This i...

Noise measured in the vicinity of an F-22A Raptor has been compared to similarity spectra found previously to represent mixing noise from large-scale and fine-scale turbulent structures in laboratory-scale jet plumes. Comparisons have been made for three engine conditions using ground-based sideline microphones, which covered a large angular aperture. Even though the nozzle geometry is complex ...

Nonlinear propagation of noise measured during static run-up measurements of a military jet aircraft is considered. Measurements made of the noise radiation from the F35AA Joint Strike Fighter indicate levels commensurate with finite-amplitude sound propagation, both through a Gol’dberg number analysis and numerical modeling. Comparisons with a nonlinear propagation model based on the generaliz...

This paper presents the evaluation of different MDO architectures using an extended set of metrics, which take into consideration optimization and formulation structure characteristics. Demonstrative comparisons are made for analytic and supersonic business jet conceptual design examples. Results show the promising features of the proposed evaluation metrics to define a standardized guideline w...

The purpose of this paper is to describe the flight crew procedures for commercial jet instrument approaches in order to aid in the development of pilot computational models and for evaluation of new cockpit display technologies. New SVS displays were evaluated based on pilot performance and workload and were compared to a baseline (no SVS) displays. Both ILS and RNAV approaches were considered...

The grounding of all commercial aircraft within U.S. airspace for the 3-day period following the 11 September 2001 terrorist attacks provides a unique opportunity to study the potential role of jet aircraft contrails in climate. Contrails are most similar to natural cirrus clouds due to their high altitude and strong ability to efficiently reduce outgoing infrared radiation. However, they typic...