Mike[_7_]
February 27th 08, 02:07 PM
Inside the Air Force
STOVL-, CV-variants less expensive than CTOL
DAVIS: BIGGEST JOINT STRIKE FIGHTER PROBLEM IS PRODUCTION COSTS
Date: February 22, 2008
In the wake of the third propulsion malfunction in six months, the
head of the Joint Strike Fighter program office says testing
difficulties are not his biggest worry in the military's largest
procurement investment to date. Instead, Maj. Gen. Charles Davis
mainly concerns himself with keeping production line costs down. On
Feb. 4, the engine that was to go onto the first Marine F-35B -- the
short takeoff, vertical landing variant (STOVL) -- failed when a third-
stage blade of the turbine came off. This event was similar to an
incident in August 2007, where an engine designed for the Air Force's
conventional takeoff and landing-variant test jet failed, Davis said
during a Feb. 13 speech at an industry conference in Washington. In
December 2007, program officials also discovered a manufacturing
defect in the lift fan rotor -- which assists the jet in vertical
landings -- of the STOVL test aircraft that required the installation
of new components. However, the two-star, who has worked on and headed
several jet aircraft test programs in his nearly 30 years of service,
has said there has not been a single program in which he has been
involved where the developers have not had some issue in the middle of
flight tests with the platform's engine. Davis remains confident that
the program has discovered and will fix the "root causes" that led to
the "high-cycle fatigue" the engine encountered, and he is focused on
making sure the first aircraft on the next-generation fighter's
production line is built "exactly the same way" as the last. "That is
the challenge we are working through right now in the F-35" program
office, the general said. "I don't worry about capabilities; I'm not
really worried about liability and logistics right now. I'm worried
about getting our manufacturing line standing down the learning
curves." Due to the number of aircraft variants, the program has cost
more and has used more titanium than originally planned, Davis said.
To stem the excess titanium used, officials are looking at how they
can streamline the production process. "We're scrapping probably 90
percent of the titanium it takes to build these airplanes because of
the way the machines cut and drill and shape parts, and we've got to
figure out what to do with that," the two-star said. "We've got to
reduce the cost of what it takes to build these airplanes." The JSF
program is learning lessons with each phase of the process, and
incorporating this new knowledge to the next phases will cut down the
cost of the STOVL and carrier-variant versions than originally
planned, Davis said. "My biggest risk has been just getting through
the planned assembly path of the airplane while I get the supplier
base up and running," he said, noting that the "planned learning
curve" of the jet is in the area of 5 to 8 percent less efficient at
this point than expected. "As we build each section, [we ask
ourselves,] 'Have we learned something from the previous section? What
do we need to do better on the next section?'"
STOVL-, CV-variants less expensive than CTOL
DAVIS: BIGGEST JOINT STRIKE FIGHTER PROBLEM IS PRODUCTION COSTS
Date: February 22, 2008
In the wake of the third propulsion malfunction in six months, the
head of the Joint Strike Fighter program office says testing
difficulties are not his biggest worry in the military's largest
procurement investment to date. Instead, Maj. Gen. Charles Davis
mainly concerns himself with keeping production line costs down. On
Feb. 4, the engine that was to go onto the first Marine F-35B -- the
short takeoff, vertical landing variant (STOVL) -- failed when a third-
stage blade of the turbine came off. This event was similar to an
incident in August 2007, where an engine designed for the Air Force's
conventional takeoff and landing-variant test jet failed, Davis said
during a Feb. 13 speech at an industry conference in Washington. In
December 2007, program officials also discovered a manufacturing
defect in the lift fan rotor -- which assists the jet in vertical
landings -- of the STOVL test aircraft that required the installation
of new components. However, the two-star, who has worked on and headed
several jet aircraft test programs in his nearly 30 years of service,
has said there has not been a single program in which he has been
involved where the developers have not had some issue in the middle of
flight tests with the platform's engine. Davis remains confident that
the program has discovered and will fix the "root causes" that led to
the "high-cycle fatigue" the engine encountered, and he is focused on
making sure the first aircraft on the next-generation fighter's
production line is built "exactly the same way" as the last. "That is
the challenge we are working through right now in the F-35" program
office, the general said. "I don't worry about capabilities; I'm not
really worried about liability and logistics right now. I'm worried
about getting our manufacturing line standing down the learning
curves." Due to the number of aircraft variants, the program has cost
more and has used more titanium than originally planned, Davis said.
To stem the excess titanium used, officials are looking at how they
can streamline the production process. "We're scrapping probably 90
percent of the titanium it takes to build these airplanes because of
the way the machines cut and drill and shape parts, and we've got to
figure out what to do with that," the two-star said. "We've got to
reduce the cost of what it takes to build these airplanes." The JSF
program is learning lessons with each phase of the process, and
incorporating this new knowledge to the next phases will cut down the
cost of the STOVL and carrier-variant versions than originally
planned, Davis said. "My biggest risk has been just getting through
the planned assembly path of the airplane while I get the supplier
base up and running," he said, noting that the "planned learning
curve" of the jet is in the area of 5 to 8 percent less efficient at
this point than expected. "As we build each section, [we ask
ourselves,] 'Have we learned something from the previous section? What
do we need to do better on the next section?'"