NIAR Web SiteAircraft InvolvementClientsContact Us


Aerodynamics
Aging Aircraft
Aircraft Icing
Composites & Advanced Materials
Crashworthiness
Fatigue & Fractures
Structures
Virtual Reality Center

AACE
CECAM
CGAR
NCAMP

 

 

 




 

November 15, 2004  -  Volume 1, Number 3

Aging Aircraft to Evaluate Beechcraft Starship


Beech Starship undergoes evaluation

In an effort to understand more about how composite, non-metallic structures age, NIAR's Aging Aircraft and Composites labs have begun research on the Beechcraft Starship.

The Starship, developed in the late 80s using an all-composite construction, was in production until December 1994, just two years after it entered commercial service.

Said to be ahead of its time, the conservative certification requirements diminished the Starship's performance and economic viability. Only 53 Starships were produced.

The program is being conducted on behalf of the NIAR's FAA Center of Excellence for Composites and Advanced Materials. NIAR Executive Director John Tomblin and Lamia Salah, manager of the Fatigue and Fracture lab, are the project's principal investigators.

Data generated from this program will provide industry with a better understanding of the aging phenomenon on the composite aircraft structure. Upon completion, the results will be used by the Federal Aviation Administration to assess the efficacy of the current emerging nondestructive investigation (NDI) methods to detect flaws.

Some of the issues the program will investigate include the changes in mechanical properties using coupon and element level testing, the degradation in physical properties and resin chemistry, the effectiveness of repairs, the material degradation due to heat, humidity and ultraviolet (UV) radiation and the bearing conditions and or failures around holes and fasteners.

The program is divided into two phases - each approximately 15 months in duration. The first phase will address NDI and materials and element level aging phenomenon of the structural components of the aircraft. The second phase of the program will address a full-scale test to assess the aircraft residual fatigue life the wing would be able to sustain after being in service for years.

"With the large number of aircraft flying with composite components, it is imperative that as an industry we understand the effects of age, both calendar and flight hour related, on composites prior to a structural failure," Melinda Laubach, Aging Aircraft manager said.

 

Three Labs to Explore 737 Stabilizer


737 Stabilizer Evaluation

Three of NIAR's labs are evaluating the aging effects on a decommissioned Boeing 737 Tail.

 The primary objective of the project is to learn more about aging the composite structures through destructive and non-destructive testing.

The 737-200 graphite/epoxy stabilizer, developed by Boeing as part of the NASA ACEE program, has been in service for 18 years.

The purpose of its development was to challenge aircraft manufacturers to redesign existing aircraft components using graphite/epoxy composites. All but two of the Shipsets have been retired.

Although the non-destructive evaluation will be performed in accordance to the current field methods, more sophisticated techniques such as 3-D Photogrammetry and laser holography are being used as well. Detailed structural evaluation will also be conducted to evaluate the changes in thermal, chemical and mechanical properties.

The ultimate goal is to understand the aging effects on the performance of the composite structure and to give recommendations pertaining to viability of composites versus metal aircraft structures.

The program is being conducted on behalf of the NIAR's FAA Center of Excellence for Composites and Advanced Materials. NIAR Executive Director John Tomblin and Lamia Salah, manager of the Fatigue and Fracture lab, are the project's principal investigators.

 






This message was originally sent to nobody.
To view this eNewsletter online, go to http://ecast.harvesthost.com/2774.

SEND this message to a friend
SUBSCRIBE to this publication
Be REMOVED from our mailing list

E-Cast Builder by Heinz & Associates, Inc.