Flight-Test Worries

Feb. 1, 2006

The Air Force’s aerospace testing establishment, long considered the world’s most extensive and technically capable, is in the throes of a developing crisis.

Years of budget austerity have made it impossible for the service to fully modernize its old and out-of-date facilities. The Air Force has been unable to create the kind of testing centers that it should have to get the most out of systems such as the new F-22 fighter and advanced concepts such as hypersonic propulsion and network-centric warfare.

The problems stem mostly from the difficulties inherent in old infrastructure. This situation could worsen, according to some of the test community’s senior commanders, unless something is done about festering budget woes.

“The reality is that budgets have been reduced, that infrastructure has continued to age, and the rate of recapitalization has not kept pace,” said Maj. Gen. Jeffrey R. Riemer, who until recently was responsible for managing the funds for the aerospace test complexes.

USAF’s testing facilities are located primarily at the Air Force Flight Test Center, at Edwards AFB, Calif., Arnold Engineering Development Center (AEDC), at Arnold AFB, Tenn., and the Air Armament Center (AAC), at Eglin AFB, Fla.

Officials say the Air Force’s recapitalization rate falls short of what is needed by the test community. That creates a gap between the capabilities of existing facilities and the kinds of capabilities needed to handle “the business coming down the road,” said Riemer, formerly director of operations at Air Force Materiel Command, Wright-Patterson AFB, Ohio, and now commander of AAC.

Emerging Problems

Maj. Gen. Curtis M. Bedke, Air Force Flight Test Center commander, also is worried about acquiring the resources needed to handle emerging technologies.

Brig. Gen. David L. Stringer, AEDC commander, said his facilities were adequately sustained and modernized under previous funding rules that required customers to pay for any new capability they needed for a test. But he was not sure what would happen under a new policy that requires the Air Force to pay for most of the resources necessary to support testing operations.

“Any time you change pricing mechanisms, you should be concerned,” Stringer said.

Until last Oct. 1, the test community operated under a long-standing set of rules. When a program manager asked for certain tests, AFMC would evaluate the capability to do that testing, Riemer explained. If new infrastructure was needed to do the job, the requesting program would pay for it. When that program’s tests were finished, the facilities remained in place.

“So the infrastructure has maintained itself and continued to be modernized at the expense of the customers who came along through time,” Riemer said.

That was then. New laws only require customers to pay the direct cost of testing. The Air Force will have to fund the cost of maintaining and sustaining the infrastructure that existed before. Indirect costs associated with that infrastructure will “have to come out of a pot of money that we manage here at the [AFMC] headquarters,” Riemer said.

Under the new law, the Air Force still is able to charge commercial customers for any new equipment necessary to conduct their tests, and because this system is new, Riemer was not sure if the new financing system would add to the funding problems.

Unfortunately, “the potential for that exists,” he said.

The US military has been intensely involved in flight testing since the first Army and Navy fliers learned how to fly their primitive aircraft directly from the Wright brothers, Glenn H. Curtiss, or other designers. (See “The First Military Airplane,” April 2004, p. 74.)

Anyone who flew in those revolutionary years was a de facto test pilot, and many early aviators paid with their lives to learn the limits and the flaws of the flimsy machines.

The military started to formalize and improve the experimentation in 1914, creating test units at what is now Naval Air Station North Island in California, then at several airfields near Dayton, Ohio, and in 1951 at Edwards.

Despite the vital importance of the test and evaluation process, the facilities and equipment at the three centers are being squeezed by stagnant defense budgets and the soaring cost of the war on terrorism.

67-Year Wait

The Air Force currently has a 67-year facilities replacement average. That may be fine for an office building, “but if it’s a test facility, with unique specialized equipment in it that you have to maintain, a recapitalization rate of 67 years is not adequate,” said Riemer. “Our biggest gap is in dealing with the future needs of test capabilities to meet the systems coming down the road.”

Bedke said the funding shortages in the test community developed because, as money has gotten tight over the past few years, the Air Force has tended to put it into the current programs as opposed to long-term investments.

That happens because, “with a war going on, people tend to focus on getting things out to the warfighters,” Bedke said. But without proper test facilities, the Air Force’s ability to support troops with modernized equipment comes into peril.

Among the things Edwards “needs right now” for its test ranges, Bedke said, are new radars, communication links, optical cameras to track aircraft, and updated range support infrastructure such as roads and working and living facilities. Some of the things Edwards uses every day “should have been replaced a long time ago,” he said.

Other facilities are becoming outdated as testing becomes more complicated. For example, the base’s data communications systems need greater data-flow capability because “we track a lot more parameters on an airplane than we used to,” Bedke said. Testers must have the means “to get data back to the control center, in real time,” so the results can be properly monitored.

The Air Force’s testing leadership is concerned that the facilities will not be able to keep up with new technologies and concepts. The test centers may be falling behind in the ability to properly evaluate systems in the face of rapid technological changes.

Of particular concern is the ability to handle what Bedke describes as “the five futures” of combat: electronic warfare, unmanned aircraft systems, directed energy weapons, hypersonic propulsion systems, and network-centric warfare.

Edwards’Avionics/Electronic Warfare Test Division has perhaps the world’s best facilities for testing electronic combat capabilities. The division’s resources include the Benefield Anechoic Facility, the world’s largest electronically secure, or quiet, environment that realistically simulates an outdoor EW range. It can hold complete aircraft, as large as the B-52, to test electronic warfare capabilities, avionics, and related systems in an integrated manner.

Although Edwards has been working to develop electronic warfare for years, Bedke said, the field is becoming increasingly complex. So the ability to monitor more parameters, and “to do it more accurately, quicker, in real time, will be increasingly important.”

The whole field of unmanned systems “is a big growth industry,” he continued. Testers are still learning the “smart way” to test unmanned aircraft, “and we need facilities and infrastructure to be able to do that.”

Edwards is testing a wide range of UASes, from the relatively small Predator to the long-endurance Global Hawk.

Brains in the Sky

The base completed testing Boeing’s and Northrop Grumman’s Unmanned Combat Air Vehicles in 2005. Edwards is now preparing to begin more complex trials with the two manufacturers’ follow-on Joint Unmanned Combat Air Systems for the J-UCAS program.

Although the J-UCAS testing will involve the airframe, flying qualities, and propulsion systems, Bedke said the real trick is “putting some really powerful computers—I call them the brains—into the sky.”

The unmanned airplanes will be required to take off and fly missions together, deciding on their own how to respond to new threats or targets.

“We must be able to test to make sure that those two systems are talking to each other in real time,” said George Ka’iliwai III, chief scientist at Edwards. For J-UCAS, that means ensuring the test center has the right frequencies and transmission capacity available to send all the data back to the control center.

Directed energy is another key future capability the community must be able to test, Bedke said. The biggest current program is the Airborne Laser, a proposed antiballistic missile weapon to be carried in a modified Boeing 747 freighter.

“That requires a whole bunch of things in infrastructure that we’ve just never had before,” Bedke said. Edwards is “probably on the leading edge of that in some ways, … but we need more.”

Work on hypersonics—systems capable of speeds greater than Mach 5—will be important in several ways. There will be tests on hypersonic air vehicles—manned or unmanned airplanes or weapons such as cruise missiles.

Studying hypersonics also helps scientists to understand the dynamics of transition into and back from space.

Arnold’s test center also contributes to the knowledge of hypersonics, by testing the ability of missiles and warheads to withstand the heat and shock of re-entry. This work is done in support of Air Force and Navy ballistic missile systems and NASA space programs.

AEDC has a hypervelocity wind tunnel capable of speeds up to Mach 20, facilities able to create the low pressure and temperature of high altitudes and space, and arc heaters to duplicate the effect of friction at hypervelocity.

The other future area Edwards must prepare for is “the one that ties everything together,” said Bedke, network-centric operations. “We are not going to be the experts in conducting net-centric warfare. But we need to help the operators who are going to be the experts in this, so we can be sure we can test all those systems together.”

Network-centric capabilities also will be important because, “if we can become netcentric ourselves, then we can test faster, more efficiently, more effectively,” he said.

Ka’iliwai said Edwards’ test capabilities also have declined as the aircraft used to support its test programs continue to age.

An annual evaluation of its support aircraft last April concluded that Edwards needed to replace 13 old F-16s with newer models and to replace virtually its entire force of T-38s, he explained.

“The flight test center still does its job,” but the geriatric equipment is making things more difficult, Ka’iliwai said.

Air Force Test Strengths

Edwards Air Force Base is Air Force Materiel Command’s focal point for test and evaluation of Air Force aerospace systems. The base is home to the Air Force Test Pilot School, which also trains navigators and flight-test engineers to help define and expand the envelope for air-breathing and space systems. (See “In Yeager’s Footsteps,” September 2000, p. 46.)

Edwards hosts an independent operational test and evaluation squadron that takes the aerospace systems that Bedke’s personnel have declared safe and effective and determines if they are ready for service in the operational forces. (See “A Combined Test Force’s Independent Looks,” below.)

Gen. Henry H. “Hap” Arnold intiated creation of the Arnold Engineering Development Center after World War II to speed up the process of getting new systems into use and to avoid being surprised by superior enemy aircraft, Stringer said.

The center describes itself as “the most advanced and largest complex of flight-simulation test facilities in the world.” The center boasts 58 aerodynamic and propulsion wind tunnels, rocket and turbine engine test cells, space environmental chambers, and other specialized test facilities. Of those, 14 are in some way unmatched anywhere else.

By testing the performance of new aircraft, propulsion systems, and munitions in its Earthbound facilities, either as scale models or full size, AEDC sharply reduces the time and expense—and most importantly, the human cost—of flight testing.

Arnold is able to test proposed aircraft and space vehicles in scale. The good news is, “with very few exceptions, … the science is pretty scalable,” Stringer said.

“So the theory of Arnold is: If I test it in scale and it doesn’t work, it absolutely isn’t going to work full size,” he said. “On the other hand, just because you test it in scale doesn’t mean that it’s going to be trouble-free at the other end.”

The flight testing is “all about risk reduction. I’m sure the test pilots appreciate that,” Stringer said, especially during the early stages of development.

“What Arnold does is extremely important to us,” said Bedke, a former test pilot. “Long before we ever take something into the air, those guys will make sure that when the test pilot climbs into the airplane the first time, we have some idea of how it’s going to react and what the physics are.”

The old practice of testing a new aircraft’s performance for the first time in flight “killed a lot of great aviators of all the services,” Stringer said, “particularly after World War II, when we started flying jets.”

It is now unusual for Air Force pilots to die because of a testing mishap, though Maj. James A. Duricy of Eglin’s 40th Flight Test Squadron was killed in 2002 when his F-15 broke apart during a test flight. (See “Aerospace World: F-15 Pilot Killed in Crash,” June 2002, p. 18.)

Eglin initially focused on helping to develop and test airborne munitions and has added the same service for complex command and control and intelligence-surveillance-reconnaissance systems, such as the E-8 Joint Surveillance Target Attack Radar System and E-3 AWACS battle management aircraft.

The Air Force also benefits from AEDC’s modeling and simulation capabilities and its wind tunnels. The systems can determine, with increasing accuracy, the interaction between an aircraft and a weapon during carriage and on release, which is of enormous benefit to the testers at Eglin.

Once Eglin declares a weapon effective and safe for release from some platforms, Edwards often takes over to test the weapon’s compatibility with other airplanes, Bedke said.

A Combined Test Force’s Independent Looks

Although the Air Force Flight Test Center at Edwards AFB, Calif., is primarily responsible for Air Force developmental testing, AFFTC regularly works with combined test forces (CTFs) that cover a broader range of testing.

Decades ago, contractors, developmental test crews, and operational evaluators each would test a new airplane separately, said center commander Maj. Gen. Curtis M. Bedke. The sequence would frequently repeat the same tests.

Now, a contractor’s experts and Air Force development and operational test personnel are combined in a CTF so they can agree on what tests are needed and can do many of the trials only once.

Although personnel from the Air Force Operational Test and Evaluation Center (AFOTEC) detachment at Edwards are included in the CTFs, they are independent and make separate judgments on the operational effectiveness and suitability of systems, Bedke explained.

For example, because some of the required tests had not been completed in initial operational evaluation, the AFOTEC unit gave only conditional approval to the F-22 when it recently evaluated the airplane. This was despite the fact that the operational test pilots and aggressor pilots that the testing unit flew against raved about the Raptor’s combat capabilities.

Edwards now is organizing its combined test force for the F-35 Joint Strike Fighter, in anticipation of receiving the first aircraft late this year.

The F-35 CTF will be different, Bedke said, because it will be joint and international, with Navy and Marine Corps personnel, representatives from Great Britain, and possibly other foreign partners.

The test community is already ramping up to support the massive F-35 program. Brig. Gen. David L. Stringer, Arnold Engineering Development Center commander, said AEDC is already conducting aerodynamic testing for the F-35 in its wind tunnels and is testing JSF engines on its ground test stands.

Otto Kreisher is a Washington, D.C.–based military affairs reporter for Copley News Service and a regular contributor to Air Force Magazine. His most recent article, “Operation Unified Assistance,” appeared in the April 2005 issue.