On 20 July 1997, as part of Joint Fleet Exercise 97-2, the USS Nimitz (CVN-68) with Commander, Carrier Group Seven, and Carrier Air Wing Nine (CVW-9) embarked began a simulated high intensity strike campaign. Four days later, they had generated 771 strike sorties and had put 1,336 bombs on target.
In the post-Vietnam era, no other carrier and air wing have generated as much firepower in 98 hours. The surge, as it has come to be known, incorporated all facets of littoral strike warfare—from weapons buildup in the magazines to ordnance delivery.
Carrier Air Wing Nine flew 975 fixed-wing sorties during the four day surge. Figure 1 summarizes the surge by sortie type and day. Naval Strike and Air Warfare Center (NSAWC) defined the terms:
- A strike sortie is one in which the aircraft penetrates hostile territory carrying ordnance; releases ordnance that enters hostile territory; or conducts electronic attack or offensive counterair operations as part of a strike package in which other strike aircraft satisfy the first criteria. Air interdiction, close air support, and suppression of enemy defenses are examples of strike missions.
- A strike support sortie is one in which the aircraft performs some function critical to the successful completion of a strike sortie. Tanking, electronic support measures, and combat search and rescue are examples of strike support missions.
- Other sorties include such missions as airborne early warning, defensive counterair, and functional check (maintenance test) flights.
Forty-two times during the evolution, aircraft that launched on strike missions did not meet the criteria for strike sorties. Figure 1 depicts these as sorties disqualified from strike.
Figure 2 is a composite of several counts. Note that almost 80% of the sorties flown were strike sorties; strike support accounted for another 10%. In turn, F/A-18s flew nearly 80% of the strike sorties. Almost all the targets were within 200 nautical miles of the carrier. These distances, which are not indicative of the maximum striking range of the aircraft, were driven by the location of the carrier operating area in relation to the target ranges. We show the maximum operational strike range that the strike-fighters could have reached, based on typical operational employment and time airborne. Weather in the target areas frequently forced strikes to divert to secondary targets, exercising the full range of command and control. Almost all strike-fighter sorties carried two 500pound or two 1,000-pound bombs (22% were live Mk 82 or Mk 83 bombs that required fuzing—see Figure 2) plus air-to-air weapons. Of the 771 strike sorties, 727 were loaded with bombs; 44 were EA6B electronic support sorties.
Only a portion of the medium range interdiction strikes required aerial refueling; U.S. Air Force KC-135s and U.S. Marine Corps KC-130s provided most of this support. Carrier Air Wing Nine S-3s conducted recovery tanking and supplied more than one-third of the total fuel transferred to air wing aircraft.
The exercise was not an isolated event. It was preceded by six days of an intense, event-driven scenario in which the entire Nimitz battle group conducted offensive and defensive operations. During these six days, the Nimitz and CVW-9 generated about 700 fixed-wing sorties.
Following this, operations paused for 16 hours during which the ship's company and the air wing got ready for the surge:
- The Air Department prepared the flight deck for high-intensity flight operations by inspecting and conducting routine maintenance on catapult and arresting gear; repainting markings on the flight deck; moving some non-mission-capable aircraft and unneeded equipment from the flight deck to the hangar bay; and configuring the flight deck for the first surge launch.
- The carrier conducted an underway replenishment so that aviation fuel stores were at maximum operational capacity.
- Ordnance crews built up bombs, loaded aircraft for the first two launches, and staged weapons in the bomb farm adjacent to the island.
- Maintenance personnel worked through the night to repair aircraft, resulting in a mission-capable rate of almost 80%.
- Strike leaders planned the initial strikes while air crews rested.
When operations began, the air crews were ready; the aircraft were groomed; and the ordnance was staged. The cost? Flight-deck and maintenance personnel began the surge after six days of nonstop, intense activity—they were tired.
Personnel augmentation proved critical. During previous high-intensity flight operations, people were the limiting factor in generating sorties. For this evolution, 257 active-duty and reserve personnel augmented the ship's company and air wing.
- The number of augmentees was artificially high. Some augmentation was required to achieve the carrier and air wing deployment manning levels. Exercise planners, cognizant of past fleet experiences, intentionally requested a higher number of augmentees than they thought necessary. Although the surge placed heavy demands on many personnel groups, some groups—such as ship's laundry, counseling, and engineering—faced normal or below normal workloads.
- Most flight-deck personnel groups—aircraft directors, plane handlers, chockmen, fueling personnel, and plane captains—were augmented and generally were able to maintain regular work schedules. The catapult and arresting gear crews—manned well below billets authorized—declined augmentation because they were reluctant to share the responsibility inherent in their jobs with individuals unknown to them.
- An Operational Strike Planning Cell was created from augmentees to allow the air crews to focus on flying. By lowering the time air crews spent on mission planning, the planning cell may have enabled the air wing to achieve greater pilot utilization rates.
- In all cases, establishing trust between the augmentees and resident personnel was critical to improved performance. Where fleet-wide practices were in place—such as the aviation community's acceptance of NSAWC procedures—integration of the augmentees was easy. Where such procedures were absent, full utilization of augmentees was delayed.
- In general, augmenting leadership positions (commanding officers of the carrier, the air wing, and the squadrons; the handler; and the air wing maintenance officer) is problematic. Instead, individuals in positions of authority might delegate to resident personnel, who would receive augmentation to help them.
Fifty-eight scheduled fixed-wing sorties were canceled during the surge; maintenance and supply were responsible for 49 of these. Typically, sorties were canceled because there were no mission-capable aircraft available. Observed mission-capable rates were consistent with rates reported by other deployed air wings except for the F-14A. The F14A mission capable rate during the surge was substantially lower than rates for recently deployed F-14As. Maintenance turnaround times can drive mission-capable rates. The biggest contributor to organizational level turnaround time was time awaiting maintenance. More organizational-level maintenance personnel might have increased mission-capable rates, particularly for the F-14As. The biggest contributor to intermediate-level turnaround time was time awaiting parts, which indicates that the inventory of repair parts was insufficient to keep up with demand.
Data indicate a low cannibalization rate across all squadrons. We did observe the F/A-18 squadrons cannibalizing critical pieces of gear that had inadequate logistic support—video recorders and APG-73 radar receivers, for example. The low cannibalization rate may have been an artifact of the short logistics chain.
Analysis indicates that the carrier and air wing had the potential to generate additional strike sorties. Under the surge master air attack plan, they might have made up some of the canceled sorties had they relied more extensively on using spare aircraft from sister squadrons. The cost for this would have been higher air crew tasking and increased workloads for the maintenance and servicing crews. Analysis indicates that they had the reserve capacities to pay these costs.
Indeed, the Nimitz and CVW-9 had excess capacity resident within their F/A-18 air crews and airframes. Free of other constraints, the air wing could have generated more than 150 additional F/A-18 sorties. Achieving that potential would have required a few more strikefighter pilots; more important, it would have required that the flight-deck crews ready 20% more aircraft—a task that would have called for additional ordnance crews, a different flight-deck loading and configuration, and the buildup and transfer of additional ordnance to the flight deck. Under a more demanding scenario, the turnaround processes would have been the most constraining factor. In hindsight; the Nimitz's flight deck probably had the capacity to process at most an additional 50 to 100 strike sorties over the four-day surge.
A carrier and her air wing can maintain high-tempo operations for just so long. Eventually, scheduled ship maintenance must be performed that could disrupt and in some cases halt flight operations. Weekly preventive maintenance and servicing activities would have allowed the carrier and the air wing to operate for, at most, three additional days before the conduct of scheduled maintenance would have affected flight operations. The air wing will eventually deplete the carrier's magazines and supply of JP-5 fuel. Based on the rates of consumption of ordnance and fuel, these would have been depleted in about one more day.
The most difficult constraint to measure is that imposed by fatigue. Although no evidence of general fatigue was present among air crews, other groups were undermanned, and fatigue was evident by the final day. Based on these factors, the Nimitz and CVW-9 could have sustained the surge operating tempo for another 12 to 24 hours.
Some additional lessons emerged:
- By sharing aircraft, air crews, maintenance personnel, and ordnance loading crews, the air wing's three F/A-18 squadrons could have flown more strike sorties.
- Under the surge operating tempo, flight-deck crews found they could manage routinely 27 to 29 aircraft on the flight deck. When the number climbed to more than 32, readying aircraft for launch became more challenging. Operators recommended that in future high-intensity operations the number of aircraft on the flight deck be held to less than 30. Continuous flight operations actually were easier to support than were start-and-stop operations.
- Moving weapons from the hangar deck to the flight deck proved to be the most difficult step in loading ordnance.
- Aircraft utilization rates observed during the surge greatly exceeded the Navy's planning factors. The Navy might consider modifying its planning factors to reflect the dependence on the operational environment and the advances in modern aircraft reliability.
- A 1+00 cycle was included in the air plan on several occasions. This cycle proved exceptionally challenging, nearly forcing the flight deck into flex mode, and it significantly increased the fatigue of flight-deck personnel. Operators felt the cycle was too short and that the cycle time should have been at least 1+15. On the other hand, to be independent of tanking, F/A-18Cs must operate on cycles of 1+20 or shorter. Therefore, unless external tankers are available, the cycle time must be between 1+15 and 1+20 at operating tempos comparable to that of surge.
Dr. Jewell, who was on board the Nimitz during the surge operations, and Mrs. Wigge are research analysts at the Center for Naval Analyses.