A Plague of Accidents

Feb. 1, 2004

Last March 17, two F-15Cs out of Nellis AFB, Nev., collided in midair during simulated air-to-air combat. The pilots suffered only minor injuries, but one fighter was destroyed when it crashed to the ground. The other sustained moderate damage.

The accident was the Air Force’s fifth midair collision in less than five months—a sobering event for service officials, who have watched aviation accident rates climb in the past few years.

In 2000, USAF had its all-time-best flying safety year. The records in the past three years have been worse—in 2002, much worse. The major aircraft accident rate in 2002 was nearly 30 percent higher than in 2000. Last year proved only somewhat less troubling.

Gen. John P. Jumper, Chief of Staff, told Air Force personnel in December 2002 that the service “cannot tolerate, nor sustain, this level of loss.”

The Air Force has made steady progress in aviation safety ever since it became a separate service in 1947. However, Jumper was concerned that USAF might have reached “a plateau” during the last decade. “While I would like to think that our [2002] mishap experience is an anomaly, I am concerned it may be a negative trend,” Jumper wrote in a memo at the conclusion of that worrisome year.

The Air Force’s Class A flight mishap rate dropped dramatically through the late 1940s and 1950s and continued a fairly steady decline until 1992. (The Class A flight mishap rate refers to the number of mishaps per 100,000 flying hours. The term “Class A” refers to mishaps that result in a death, permanent disability, loss of an aircraft, or damage of more than $1 million.)

In 1947, this benchmark rate was 44.22. Twelve years later, it fell below 10 for the first time. In 1983, the rate fell below two for the first time. Ever since, it has been in the “ones,” but progress beyond that has been hard to achieve. All obvious, easy fixes have been made.

Air Force officials say the service goal is zero accidents. Is that target realistic? Maj. Gen. Kenneth W. Hess, USAF chief of safety, pointed out that, “what we [Air Force members] do is, by definition, dangerous.”

The Air Force is not an airline and will always fly a large number of inherently risky combat missions, frequently in single-engine aircraft. Even training missions are dangerous. “We are in a high risk business,” said Hess.

The Human Factor

Officials found human error to be a common thread in the accidents. The USAF analysis showed that two-thirds of the 2002 accidents resulted primarily from human-factor issues, which generally means poor situational awareness during flight.

In the case of midair collisions, a pilot’s loss of situational awareness is frequently cited as a determining factor. “You really have to hammer away at the fact that these mishaps are preventable,” Hess maintained.

Hess said that he had never seen an unpreventable mishap. Lessons learned from previous accidents work their way into the system in the form of improvements to parts, procedures, and training.

The Air Force safety program, said officials, relies on commanders to ensure that their personnel are properly trained and that safety remains uppermost in the minds of airmen.

“We will get better,” Hess asserted, adding that “nobody is naive” about the difficulty of the task. Some improvements will take time. Changes in training and procedures, for instance, can take two years or more to implement.

In the period 1993 to 2002, USAF lost 85 aircraft and suffered 18 fatalities in accidents stemming from power plant and other systems failures. In the same period, human error caused the loss of 127 aircraft and 244 personnel. Some human factor-type accidents are controlled-flight-into-terrain (CFIT), pilots losing control in flight, and midair collisions.

Officials said that CFIT errors take the greatest toll on the Air Force. They claim an average of 13 fatalities and six aircraft per year, according to USAF data. Typically, the problem is aircrew loss of situational awareness.

However, the Air Force has not found a systemic training or awareness problem that accounts for CFIT accidents. Hess said that the very nature of combat flight makes CFIT accidents an ever-present danger. Pilots flying and maneuvering at high speeds, frequently at low altitudes, are vulnerable to crashes. The safety chief said the Air Force must simply work to drive their frequency as low as possible.

“What’s left for us is to concentrate on the humans, where the humans make errors and mistakes,” Hess said.

Beyond human error, the service can find no “smoking gun” in the recent accidents. The mishaps did not have a single predominant cause, as was the case in the mid-1990s, when severe engine reliability problems caused many F-15 and F-16 crashes.

From 1993 through 1997, single-engine F-16 fighters each year had the most engine failures of USAF aircraft. An extensive engine improvement program brought down the number of power plant-related crashes.

In 2003, a variety of factors were at work, ranging from bird strikes and single-bolt failures to blown tires and catastrophic engine flameouts.

The Optempo Issue

A potential contributing factor has been USAF’s high operational tempo since 9/11. One USAF safety analysis reported, “Flight crews pressing for mission accomplishment despite high operational risk factors drove an [operations] spike in FY02.”

In an interview last fall, Jumper agreed that operational tempo can affect flight safety. “I’ve just seen this over a number of years—this general correlation between stress level and mishap rates,” said the Chief of Staff. The pace of recent operations has resulted in “supervision stretched thin [and] maintenance stretched thin,” Jumper added, though he noted that operational strains are “not an excuse” for safety lapses.

“When you get busy, and you’re thinking about your next deployment, … and it’s rush, rush, rush, that’s when the safety aspects start to drift away,” Jumper explained. Steps to enhance safety “need to be brought back to center,” he went on. “That’s what our emphasis has been.”

It is difficult to prove a direct correlation between mishaps and operational tempo. Though it seems logical that high optempo contributes to mishaps, stress on the force is almost never cited as a probable mishap cause, said retired Maj. Gen. Timothy A. Peppe, a former chief of Air Force safety.

“When you go digging in” to the root causes of a crash, Peppe said, “you cannot tie them directly to the optempo.” Something else is almost always found to be the culprit.

An exception was the Feb. 13, 2003, crash of an Air Force Special Operations Command MH-53M while landing at the Udairi Range in Kuwait. The 16 troops aboard the helicopter had completed a realistic, nighttime training mission. None were seriously injured, but the helicopter sustained damage of more than $15 million.

A USAF accident investigation board laid blame for the mishap on “a combination of inadequate mission preparation and aircraft design deficiency.” The aircrew had not sufficiently studied the planned landing site to determine its acceptable landing tolerances. Consequently, “the pilot landed on terrain that did not accommodate his touchdown profile,” according to the accident report.

Bad Year for Helos

USAF helicopters, as a rule, have had low mishap rates over the years—until 2002, that is. In that year, the USAF helicopter community suffered more Class A mishaps than it had since 1969, a year of high Vietnam War activity.

In 2002, USAF sustained 25 operational aircraft mishaps, nine of which involved helicopters. Of those nine accidents, four occurred in Southwest Asia. In 2003, the number of helicopter mishaps dropped to four.

The helicopter Class A mishap rates in 2002 and 2003 were 15.74 and 5.96, respectively. The fighter/attack aircraft rates for those years were far lower, 2.16 and 2.54.

Hess cautioned that it is a mistake to become fixated on the mishap rates in any single year. Too many “curious things” can lead to an unrepresentative spike in the rates, he argued.

“Can we improve?” Hess asked. “Can we get better than a 1.4 [overall] mishap rate? I think the answer to that question is yes.”

Hess noted that the next generation of airplanes will be far more reliable than the older generation of C-5, F-15, and F-16 aircraft, which are based on technology that is 25 to 30 years old.

“It’s a generational thing,” he said.

C-17s, F/A-22s, and F-35s—all designed with advanced computers and with years of data about airplane crashes—in a few years will dominate USAF’s fleet.

Of course, new systems tend to produce more surprise mishaps. Such is the case with today’s C-17. It is highly reliable, but, when it breaks, it breaks in unexpected ways.

Still, even with the surprises inherent in new systems, Hess emphasized, “I think we’re going to be able to move to another level of safer operations.”

Rumsfeld Weighs In

The rise in aviation mishaps across all services during 2002 prompted Defense Secretary Donald H. Rumsfeld to set a new goal. Each service was called on to cut mishaps and mishap rates in half by 2005.

“World-class organizations do not tolerate preventable accidents,” Rumsfeld declared in a May 2003 memo.

In 2002, accidents claimed 82 personnel and 63 aircraft. Air Force accidents accounted for 22 fatalities and 19 destroyed aircraft.

The Defense Department must “turn this situation around,” Rumsfeld wrote. He called the new goal “achievable” and said it “will directly increase our operational readiness.”

Reducing mishaps by 50 percent in two years is ambitious. Each service already takes safety seriously. However, USAF’s chief of safety, Maj. Gen. Kenneth W. Hess, said that it is good to “put a marker out there.”

Whether the goal is attainable is irrelevant, Hess said, because the ultimate goal is zero mishaps.

In 2003, the Air Force had three fewer mishaps due to accidents and reduced its Class A mishap rate from 1.48 in 2002 to 1.39 in 2003. (For comparison with the other services, see the table below.)

Rumsfeld tasked DOD’s personnel and readiness director, David S.C. Chu, to lead the mishap reduction effort. Chu later established the DOD Safety Oversight Council and established several service-led task forces to develop ideas and plans. Air Force general officers head two of the task forces.