Defense

June 14, 2013

AEDC site of choice for unique T-6 Texan II engine test

Tags:
Philip Lorenz III
Arnold AFB, Tenn.

A frontal view of the Pratt & Whitney Canada PT6A-68 turboprop engine installed in AEDCís SL-1 test cell includes a special shroud to provide a simulated flight environment for the propeller. Without the shroud the propeller would create a pulse every time the blade passes at the closet point to the bottom of the test cell.

The Arnold Engineering Development Center at Arnold Air Force Base, Tenn., s the site of choice for a unique engine test currently underway in the Complex’s Sea Level 1 (SL-1) test cell.

The Pratt & Whitney Canada PT6A-68 turboprop undergoing testing at AEDC powers the Texan II that is used by the U.S. Air Force for basic pilot training and the U.S. Navy for primary and intermediate joint Naval Flight Officer and Air Force combat systems officer training.

When asked why the Air Force Life Cycle Management Center’s Propulsion Directorate decided to bring the PT6A-68 turboprop engine to AEDC for a nine to 10 month Accelerated Mission Testing (AMT), Hugo Heyns, Air Force Life Cycle Management Center’s Propulsion Directorate, Propulsion Acquisition Division PT6 Integrated Product Team lead, said the answer is simple.

“The PT6 Integrated Product Team, in concert with the JPATS System Program Director, determined that an AMT would provide an early understanding of engine failures allowing time to address them before they affect the fleet, thereby assuring continued success of the PT6 engine,” he said. “Further, that the program would be better served with an AMT conducted by an accurate and objective test facility with extensive aircraft engine testing experience. The U.S. Air Force’s AEDC clearly fits that description.”

The Pratt & Whitney Canada PT6A-68 turboprop engine installed in AEDCís SL-1 test cell includes a special shroud to provide a simulated flight environment for the propeller. Without the shroud the propeller would create a pulse every time the blade passes at the closet point to the bottom of the test cell.

This is the first time a T-6 Texan II engine has undergone an Accelerated Mission Test (AMT) at AEDC’s SL-1 test cell. The test represents a number of other firsts, including the first use of a propeller for loading the engine.

“This test is the first project where ATA has been contracted to provide maintenance and inspection services in addition to the installation and operation of the engine and support systems,” said Brian Knack, a turbine engine project manager with AEDC’s Aeropropulsion Branch. “We’re also doing a dynamic analysis on the rear of the engine – the auxiliary gear box. We’re trying to define the vibration modes at the rear of the engine where some parts have been failing in the field. Even though the engine is lightly instrumented, we will be measuring a number of performance parameters, including vibration, fuel flow, airflow and trending engine speeds.

“We’ll be relying on the engine parameters that are within the engine control that we’re going to be reading in addition to some test cell measurements that we’ll be making.”

Air Force photograph by Rick Goodfriend

Before testing can begin at AEDCís SL-1 test cell, Chris Rogers, an AEDC engineer, conducts a borescope inspection of the PT6 engine that powers the T-6 Texan II trainer aircraft.

Further, Knack said “This test is an endurance test on the PT6A-68 engine. It’s an overhauled engine – it’s not a new engine. We’re evaluating the durability of the engine through its second overhaul interval. We’ll be putting a whole overhaul interval’s worth of test life on this engine during this test.”

Lt. Sam Stephens, AEDC’s project manager over the test, said, “Primarily, we’re continuing this pacer engine’s life at an expedited rate. This engine is going to have about twice the [flight] hours as any other PT6 in the T-6 trainer fleet. Maintenance and durability is our primary concern [with this engine].”

During the nine to 10 months of testing, the PT6A-68 will be subjected to the number of Total Accumulated Cycles an engine would experience in flight between depot overhaul periods. TAC is a unit of measurement for major rotating engine components tracked during an engine’s operational life.

Heyns said, “The PT6 AMT is intended to provide visibility into the future of the Joint Primary Aircraft Trainer System program engine fleet, identifying and defining issues of concern which may have impact on the fleet in sufficient time to take preventative and/or corrective actions before actual impact to the fleet’s availability.”

The PT6 engine is a derivative of a commercial engine with significant operational history in a wide variety of applications – the engine was selected, in part, because of this history.

Considering the JPATS mission is somewhat different than many of the engines other applications, initial engine modifications were used to address them.

Heyns said, “For example, the JPATS need for inverted flight demanded oil systems modifications to assure continued oil flow during inverted flight. Program engineers have also identified possible sources of future failures – and will use the AMT to study them in more detail.”




All of this week's top headlines to your email every Friday.


 
 

 

Headlines November 17, 2014

News: Fight over A-10 re-opens Hill, Air Force divide - After a relatively quiet summer, the battle for the future of the A-10 Warthog exploded in the last two weeks, reopening deep fissures between Congress and the Air Force that seem to show the two sides at a total stalemate. Chances for sequester relief fade as...
 
 

News Briefs Nov, 17, 2014

Second stealthy destroyer starting to take shape The second of three stealthy destroyers under construction in Maine is starting to take shape. The Navy says it has completed the hoisting of the 1,000-ton composite deckhouse onto the 610-foot hull of the future USS Michael Monsoor. It took four cranes to complete the job Nov. 14....
 
 
NASA photograph by Jim Yungel

NASA DC-8 continues west Antarctic ice study

NASA photograph by Jim Yungel The Thurston Island calving front off of western Antarctica as seen from the window of NASA’s DC-8 flying observatory Nov. 5, 2014. NASA’s DC-8 flying laboratory has two weeks of suppor...
 

 
NASA photograph by Emmett Given

NASA opens registration for 2015 Exploration Rover Challenge

NASA photograph by Emmett Given Pedaling across a simulated alien landscape of rock, craters and shifting sand is one of the nearly 90 teams of high school, college and university students from across the United States and arou...
 
 
Lockheed Martin photograph

Lockheed Martin begins final assembly of NASA’s next Mars lander

Lockheed Martin photograph Technicians in a Lockheed Martin clean room prepare NASA’s InSight Mars lander for propulsion proof and leak testing on Oct. 31, 2014. Following the test, the lander was moved to another clean room ...
 
 
Air Force photograph by Isaac Cruz

‘Batman’ fix to sustain C-5s for decades, saving millions

Robins Air Force Base, Ga., has hit another milestone by being the first to complete a new major structural repair on a C-5M which will bring in millions of dollars in revenue and sustain the Air Force’s fleet for decades...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>