AMPTestFE Posted April 27, 2017 Share Posted April 27, 2017 Ok, so I'm out at base X flying our 4 '74 models and notice a trend. After climbing up to our cruise ceiling, we can't true out until an hour or two later....so I started running some other charts. I first would watch our TAS until we just hit 300, then took a snapshot of average torque, gross weight, OAT, alt, etc. I would then run the IAS for 300TAS chart, which might have come out with something like 12,000 in lbs, before the drag correction. On page 2 (drag correction), I would correct for our advertised ~+20 index, and would come up with a value much less than what it just took us to creep up to 300 TAS. So then, I would come in backwards with my average actual torque on the left, then intersect with the charted value from the bottom. For each of our 4 airplanes, the result varied from a +70 to +60 drag index. On subsequent flights, I would calculate our cruise ceiling with this new value. When we'd get to top of climb, guess what...we'd true out almost exactly at 300. I know some will ask about engine performance, but this method takes that out of the equation. Torque is torque, regardless of engine performance values. And no, we didn't forget the flaps.... So....has anyone else noticed the H being too draggy like this? I'm wondering if the engineers mis-calculated the drag value of LAIRCM or something. Quote Link to comment Share on other sites More sharing options...
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