Gulf War Air Power Survey
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- Figure 68 Surge Requirements and Production (Cumulative)
- Quantitative Logistics Indicators
- Break Rates and Fix Rates
- Figure 69 F-16 FMC Rate Table 36 Fully Mission-Capable Rates Compared
- Sourcing Command Aircraft FMC Rate Before
- Table 36 (Continued) Fully Mission-Capable Rates Compared Sourcing Command
- Avg (adj) Desert Storm Avg (adj)
- Figure 70 F-15 Break and Fix Rates 37 Why Were Capability Rates Better Than Expected
- Comparison with Other Services
- Table 37 Rationale for Differences Between April 1990
- Aircraft Type April 1990 Assessment Rationale for Difference
- Table 37 (Continued)
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Before the Gulf War, increased demands on the C-141 fleet (primarily low-level flying and increased heavy-weight refueling) accelerated structural damage to the aircraft, with a corresponding reduction in service life.690 The severity of the problem led the Military Airlift Command Council to conclude in May of 1990 that maintaining a viable fleet would not be possible beyond the turn of the century.691 Naturally, the increased flying tempo during the Gulf War held the possibility of exacerbating the problem. To minimize impact, Hq MAC and 21st Air Division both put zero fuel weight and gross takeoff weight limitations on the aircraft.692 The impact of these decisions (although the precise trail of logic is not recoverable) was to restrict C-141 loads to twenty short tons.693 The Command later estimated that this restriction reduced C-141 airlift capability by six to ten percent.694 Although the Gulf War resulted in about three years worth of flying hours during a one-year period, the effect on the C-141 fleet was to shorten fatigue life by about one year. The reason for the moderate impact was reduced exposure during the Gulf War to stressful flight profiles such as air refueling, air drop, and low-level flying.695 Industrial Maintenance Air Force Logistics Command and its contractors participated in the Gulf War primarily by (1) increasing production of repair parts, (2) accelerating the output of aircraft from program depot maintenance lines, and (3) fielding combat logistics support squadrons. The first of these is called repairable surging. The normal peacetime production rate of repairable (sometimes called “exchangeable”) items is 60,000 per month.696 “Repairable surging” is increasing the rate at which Air Force Logistics Command “turns around” repairable items such as avionics line replaceable units and aircraft engines. An item was considered surged if it was either already undergoing repair and turned out faster than normal or entered earlier than normal into the repair process (and then repaired). Overall Logistics Command surge performance is depicted in Figure 68. As can be seen from the figure, the surge production (i.e., production over and above normal) rate was approximately 6,700 per month from late August through mid-January and then climbed to 18,000 per month after mid-January.697 Note that production was linear in the two periods before and after mid-January and fairly independent of the requirement. Throughout the January, February, and March periods, production trailed demand by about 10,000 components. It is not certain why this was so, but a reasonable conjecture based on after-action reporting is lack of carcasses to repairthe same problem the Air Force Queen Bee engine shops in Europe experienced.698 Overtime rates varied widely, with some units reporting rates as low as seven percent and others as high as eighty percent.699 Figure 68 Surge Requirements and Production (Cumulative) 36
Quantity produced is one consideration; a second is: were the right things being produced? To quote from two after action reports from the same Air Logistics Center (ALC): This [Command and Control Information] system was used to electronically transmit surge requirements to the Avionics Surge Center. The electronic data interface greatly speeded the surge notification process.700 Each ALC has their own rules on how to compute surge candidates. MAJCOMs and ALCs need to agree on how to identify surge candidates and how requirements will be computed. The local CCIS was completely ineffective in identifying quantities and tracking.701 The implication is that although requirements identification was fast, it was not necessarily accurate. The view that surge requirement identification and tracking was problematic is corroborated in other after-action reporting.702 However, it is also apparent that by the phase II deployment (mid-September 1990), much of the initial confusion had died down as customers (e.g., Air Force Special Operations Command, Tactical Air Command, Strategic Air Command, and Military Airlift Command scrubbed the initial lists generated by the Weapon System Management Information System and switched to using reports of actual War Readiness Spares Kit shortages and mission capability limiting items.703 Finally, confusion existed over how surge was to be implemented and the purpose of Air Force Logistics Command's Surge Contingency Plan 70. The plan, as viewed by Logistics Command Headquarters and as stated in the introduction to the plan, was not intended to be implemented but was a guide for writing air logistics center-level plans.704 This intent was consistent with a concept of decentralized decision making on when and what to surge. But at the level of the air logistics centers, the expectation evidently was that Headquarters would make the decision to surge and that “Plan 70 should be implemented early to ensure consistent implementation across the command.”705 One result of the confusion over who was supposed to decide to surge was an initial delay (of some weeks duration) as each weapon-system program manager “convinced” other ALCs and peer directorates within the same ALC to respond to surge requirements.706 The Air Force referred to production of an aircraft undergoing program depot maintenance earlier than originally planned as “acceleration.” AFLC accelerated approximately seventy aircraft during Desert Shield and Desert Stormsixty-four within AFLC industrial facilities and another six that were undergoing program depot maintenance at contractor facilities.707 Of the seventy aircraft, four were C-5 aircraft and thirty-five were C-141s.708 The acceleration provided for almost 1,000 additional flying days. However, the additional flying days were not fully used.709 For example, Military Airlift Command used approximately one-third of the 174 additional flying days made available on C-141 aircraftthe rest of the additional C-141 flying days were unused. Chapter 3 shows that, except at peak periods, more C-141 mission-capable aircraft were available than required; this should not be a surprise, but it does reinforce the point that industrial maintenance capability exceeded the demands placed on it. Quantitative Logistics Indicators One of the impressions apparently created during the Gulf conflict and then perpetuated afterwards is that Air Force aircraft had mission-capable rates “equal to or better than” peacetime rates. Often, the emphasis was on “better than.”710,711 The mission-capable rates were generally good, but they were not that good. With the exception of a few aircraft such as C-141swith rates slightly higher in Desert Shield and Desert Storm than in peacetimethe mission-capable rates of all other aircraft appear to have stayed about the same or decreased when compared to peacetime rates.712 The text below assesses mission-capable rates, break rates, and fix rates. Mission-capable rate is a composite of many factors and thus inherently integrates the effects of design, policy, spares levels, manning levels, and other influences. The break rate is the number of returning sorties that need repair and is driven mostly by the basic reliability of the aircraft. Repair rate is the number of returning aircraft ready to go in a given amount of time (e.g., eight hours) after landing. Although repair rate is a function of inherent maintainability, it also reflects maintenance capability and spares availability. By considering all three rates (fully mission-capable, break, and fix) it is possible to get a feel for the influence of more immediate factors as well as those of longer duration. Air Force mission-capable rates can be compared with those of other Services, since the definition of the term is generally consistent across Services. Mission-Capable Rates Because the Core Automated Maintenance System (CAMS) was never fully fielded, reliable mission-capable rates were difficult to obtain during or after the conflict.713 As a workaround, the CENTAF (Rear) battle staff at Langley AFB telephonically obtained once-per-day snapshots as of midnight in Riyadh.714 The snapshot flying data inflated the mission- capable rates by about five percent to seven percent compared to rates that would have been obtained with the automated system. This inflation may be a source of the impression that the mission-capable rates were better than in peacetime.715 Military Airlift Command collected data manually for a different reason. The combination of CAMS and the Reliability and Maintainability Information System (REMIS) assumed that a Military Airlift Command aircraft remained mission-capable from the time it left home station until it returnedthis practice also produced inflated fully mission-capable rates.716 For the C-5, the inflation was as much as ten percent during the Gulf War. Another factor influencing the validity of the comparisons between wartime and peacetime rates is that a month-to-month variability (of say five percentage points or more) occurs normally without obvious cause. Hence, a value of five percent difference in either direction should be viewed skeptically. The pattern of the F-16's mission-capable rate is typical of Tactical Air Command aircraft. In Figure 69, the upper line is the reported rate and the lower line is the reported rate less six percent (i.e., the average inflation due to snapshot data collection). July was the last month before deployment. From the figure, the reader can decide that deployment initially degraded mission capability. However, most of the bugs were worked out of the system in roughly four months. Table 36 contrasts the average fully-mission-capable rates before deployment, during Desert Shield, and during Desert Storm for major U.S. Air Force aircraft. Break Rates and Fix Rates Why did the mission-capable rates go down in general after deployment? The answer can be seen in break and fix rates.717 Tactical Air Command aircraft all followed a more-or-less common pattern that
F-16 FMC Rate Table 36 Fully Mission-Capable Rates Compared718
can be visualized by examining F-15 data (Figure 70). F-15 aircraft deployed to the AOR broke more often than did aircraft at home. It is not hard to understand why. Over and above being in a harsh environment, aircraft in the AOR were flying longer sorties than peacetime training missions. In addition, the rate at which broken aircraft in the AOR were fixed was worse than the rate at home station (although the AOR rate improved over time as the supply system, intermediate maintenance, and other capabilities came fully on line). For the C-5, maintenance ability to repair aircraft rapidly enough between missions appears to have been the limiting factor. As is discussed in chapter 3, Military Airlift Command flew all C-5 aircraft that were mission capable. Figure 70 F-15 Break and Fix Rates 37
Why Were Capability Rates Better Than Expected? Although capability rates were not as good as appeared from the initial data, they were still better than ones forecast as late as April 1990. In that month, the AFLC Logistics Operations Center assessed Logistics Command's ability to support OPLAN 1002-90. The Center concluded that Logistics Command could fully support only two of thirteen aircraft types tasked in the OPLAN; the B-52 and C-141 were actually rated as unsupported.719 Because of the disparity between prediction and outcome, the Command performed an after-the-fact assessment during the summer of 1991 to uncover the reasons for the differences. Results are summarized in Table 37.720 Three common threads run through Table 37. First, aircraft such as the F-4G and the F-16 simply “got well” between the initial assessment and the Desert Shield and Desert Storm deployment. Second, nondeploying aircraft and their WRSKs kits were extensively cannibalized.721 Third, only small proportions of the respective fleets usually deployed, making extensive cannibalizing practical. Those that remained home became a ready source of supply for those that did deploy. The April assessment assumed there would be no cannibalization from nondeployed aircraft or their WRSKs. Comparison with Other Services Navy experience was essentially the same as Air Force experience. Eight carriers participated in Desert Shield and Desert Storm. The Center for Naval Analyses (CNA) analyzed the mission capability data and concluded that the Navy mission-capable rates were as high as those normally experienced in peacetime,722 although CNA did not provide the equivalent peacetime rates. CNA's summary data for Desert Shield and Desert Storm are presented in Table 38. Reasons given for the sustained mission-capable rates were (1) flying-hour usage rates were near planned wartime numbers, (2) carriers shared intermediate maintenance facilities, (3) and a healthy supply stock was available.723 A quantifiable measure of supply health is the range and depth fill rates of the Navy's Aviation Coordinated Allowance List and rotable pools.724 Fill rates are given in Table 39. Table 37 Rationale for Differences Between April 1990 OPLAN 1002-90 Assessment and Desert Shield/Desert Storm Results725
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