---

Project Objectives

The entire AvSP was created based upon a presidential initiative to make air travel safer. The AvSP and Ultra Safe project address the safety objective of Goal One, Revolutionize Aviation that states, "reduce the aircraft accident rate by a factor of five by 2007 and by a factor of 10 by 2022." Ultra Safe also supports, secondarily, Goal Three, objective 9 and 10, Engineering Innovation and Technology Innovation respectively. The project objective is to eliminate the propulsion system as the cause of aircraft accidents.

The Ultra Safe Project will improve upon the state-of-the-art technology for crack resistant materials, engine containment and blade-out mitigation. This work will encompass research and development of advanced materials, structural concepts and all of the enabling methodologies for modeling, analyzing, designing, and testing at all relevant scales from material coupons through full scale systems. The accomplishment of this project will ultimately contribute to safer, lighter-weight, lower cost and more robust disk materials and containment systems.

The Ultra Safe Project's technical challenges are to 1.) Develop a lightweight containment system that withstands the physical forces of fragmented engine components, and 2.) Create durable and fatigue resistant alloys: TiAl, Ni-based superalloys and advanced powder metallurgy superalloy.

[Top of Page]

---

 

Technical Summary

The goal of the Ultra Safe Propulsion Project is to reduce engine component failure to an absolute minimum and to contain all possible fragments should an occasional failure occur. To achieve this goal, two technical approaches/sub-projects will be pursued: engine containment and blade-out mitigation and crack resistant materials. The engine containment sub-project team will develop enhanced, lightweight engine containment materials/systems. The technical challenge for the team is to develop containment systems that can withstand the physical forces of fragmented engine components. The concepts will be tested in-house, in the Ballistic Impact Laboratory, a key facility for this project. Several types of materials and structures will be tested. Both sub-scale and full scale testing will be conducted to assess the best candidate containment systems for the AvSP. State-of-the-art research and development will be done with advanced materials, structural concepts, and enabling methodologies for modeling, analyzing, designing, and testing, at all relevant scales, material coupons through full scale systems. Analytically, researchers are studying the dynamics of impact and characterizing that behavior in order to design a better containment structure. This research is being coordinated with the FAA since all containment structures must be certified with a blade-out test.

In crack resistant materials, the goal is to develop long life, durable engine component materials to double resistance to failure. The approach is to use the extensive knowledge base that exists at GRC on the current bill of materials for blades and disks. Our research will be aimed at creating durable and fatigue resistant alloys of TiAl, Ni-based superalloys and advanced powder metallurgy superalloys. Current day failures will be analyzed to understand the sequence of events and modifications will be made in the design/processing/manufacturing cycle based upon the results. In addition, new crack resistant alloys will be developed. Resulting technology will not only be more durable which impacts safety, but it will also require less inspection which reduces maintenance costs impacting overall DOC+ I.

Ultra Safe will use the following in-house facilities:

[Top of Page]

---

 

Milestones

Milestone	Output	Outcome
US-1.1 Demonstrate cast gamma-TiAl has sufficient durability to allow the design of robust low pressure turbine applications (09/01)	Quantify at least six life reduction factors identified as critical to demonstrating the durability of cast TiAl for LPT applications	Enable low pressure turbine blades to be designed safely and reliably from cast TiAl in advanced engine design concepts
US-1.2 Mature Ultra Safe propulsion technologies transferred to Aviation Safety Program (9/02)	New composite/hybrid "hard wall" and fabric "soft wall" containment system structural concepts transferred to the AvSP for full-scale evaluation.	Validated structural concepts, which could be developed into safety-certified, lighter-weight, lower-cost, and more robust containment systems.
US-1.3 Develop reliable life prediction concepts for advanced Ni-based turbine disk superalloys (09/03)	Utilize the experimental data to develop a fatigue life prediction model based on the combined effects of residual stresses and inclusion size and distribution	Validate life prediction methodology for critical powder metallurgy superalloy components on test specimens and develop technology to TRL 3.

[Top of Page]