MIL-DTL-62177E AVDS-1790-2 Engine Series Specification Download
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MIL-DTL-62177E 20 TABLE VII. First article endurance test cycle - Continued. Period number Period length (minutes) Gross hp rpm Period number Period length (minutes) Gross hp rpm 38 5 300 1600 84 5 Idle 39 5 Idle 85 15 300 1600 40 30 750 2400 86 5 Idle 41 5 460 1800 87 70 750 2400 42 60 750 2400 88 5 Idle 43 5 Idle 89 5 200 1400 44 5 Stop 90 30 Idle 45 5 300 1600 91 Stop 0 0 46 5 Idle 20.5 hours 4.6.4.1.2.1 NATO endurance test results. During the NATO standard engine test AC/225 (panel II) D 131 (part II), the engine performance and other characteristics (parameters) shall be measured/calculated and monitored as follows: a. Pre- and post-test performance. Before and after the test, and at the end of each 100 hour period, a full power setting corrected performance test curve (see figure 1 for a sample) shall be plotted from measurements taken at a minimum of seven speed settings in descending order, the first setting being at the rated speed. The speeds to be run include 1200, 1400, 1600, 1800, 2000, 2200 and 2400 rpm. b. Oil consumption. The quantity of oil in the engine shall be checked with the engine dipstick at the idle period of each 5-hour cycle and oil shall be added to reach full mark on dipstick. Quantity of oil added shall be recorded. Brake specific oil consumption shall be calculated every 50 hours based on oil used and average horsepower hours run. c. Fuel leakage. At the conclusion of each 100-hour test period, the engine cooling fans shall be removed and fuel injection lines, nozzles, pumps, etc. shall be visually inspected for defects and fuel and oil leaks, and the results recorded. d. Engine output checks. At the conclusion of each 100 hour test period, the engine shall be operated at 2400 rpm full power setting. The fuel flow shall be checked and adjusted within 2 pounds per hour (lb/hr) (0.907 kg/hr) of that observed for the pre-test performance test specified in 4.6.4.1.2.1.a. The details of any adjustments made shall be recorded. Then the engine output shall be calculated and recorded. e. Engine parameters. The following engine parameters shall be monitored at the end of period numbers 2, 4, 5, and 6 of the test except as noted: 1. Engine speed, rpm. 2. Engine load, torque, lb-ft. 3. Intake manifold pressure, in. of Hg.