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    Crashes in the News - Thread

    While cockpit recorders, and their data, are available by agreement outside China, the motives and other details are not as likely to be known or be granted closure. The earthquakes that flattened 5300+ kids in China were hidden for years from the public. And landslides that buried hundreds of...
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    Tell me why it's impossible, I'll tell you how I did it.

    Whatever works, frankly. Lots of things work eventually. I couldn't brook a winter anywhere near 65N. The few melanin producing cells I have would go on strike.
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    % loss of hp / 1,000-ft ?

    If optimal mixture is maintained, the effective compression ratio drops nonlinearly to a) reduce efficiencies nonlinearly, b) reduces surplus thermal energy that causes ideal gas law expansion in a nonlinear fashion. Pumping losses go down with altitude for constant power for an Otto cycle...
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    YouTube star plays stupid game, wins stupid prize...

    If people get to turn airplanes into unguided missiles for fun and profit, do I get to start collecting CEP (circular error probable...a measure of targeting accuracy) values by adding lateral and terrestrial guidance to my missile...errr....high powered rocketry efforts? I promise I'll plan the...
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    % loss of hp / 1,000-ft ?

    The friction losses for the engine are also more or less a fixes price per cycle as well. This means that power losses for density altitude are more nonlinear than the roughly linear reductions in mass flow rates at increasing altitudes. The change (decrease) in net power per stroke increases...
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    15% ethanol to be allowed in "normal" auto fuel?

    If more recent data than the 2014 Brazil data is needed (which is not really the case in the presence of a reasonable experiment and data without substantial controverting evidence), then 2021 https://www.sciencedirect.com/science/article/abs/pii/S1352231021005100 2021...
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    15% ethanol to be allowed in "normal" auto fuel?

    https://www.scientificamerican.com/article/ethanol-fuels-ozone-pollution/ The story, as usual, is more nuanced as you e mentioned. Ethanol produced in the US has a higher GHG footprint than gasoline, effects higher ozone at blends that are feasible for the US fleet, and alternatives like MTBE...
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    15% ethanol to be allowed in "normal" auto fuel?

    First pair of Google hits from "ozone attainment ethanol": https://news.stanford.edu/news/2009/december14/ozone-ethanol-health-121409.html https://cfpub.epa.gov/si/si_public_file_download.cfm%3Fp_download_id%3D504563 The vapor pressure is problematic for using ethanol in ozone attainment...
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    15% ethanol to be allowed in "normal" auto fuel?

    US corn based ethanol likely warms the planet faster than even direct use of fossil fuels, unfortunately. I have nothing against ethanol as a means to reduce CO. And it's a substitute fuel. But it makes ozone tougher to deal with. And it makes reducing GHG harder in the US, apparently.
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    15% ethanol to be allowed in "normal" auto fuel?

    First, higher ethanol means higher ozone in many locations that are struggling with ozone nonattainment. Reformulated gas, which is already 35 to 65 cents more, is the only way to address ozone. Ethanol increases will not be allowed in those areas. MTBE, lower benzene, etc are what will be...
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    Hand-thrown Airframe Parachute

    I have wings with a few hundreds of hours of flying on them, and that equates to 2x that for overall exposure (from "parawaiting/hang waiting"). The drying and packing time is insignificant. The hours in the sun at the tops of some of Colorado's 14ers and other high altitude launches while...
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    Hand-thrown Airframe Parachute

    I've tossed the reserve over water anymore of times while taking a paraglider aerobatics class. I wore a life preserver, with was little comfort when a wing and the reserve essentially immobilized you until the boat moved in to help. Opening was snappy. It was not comfortable hitting the...
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    Chinese Delivery UAV with 12,000 lbs MTOW in Full Commerical Operation

    So is a C-150. I'm not concerned. I wonder if it is autonomous or FPV for takeoff and landing...
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    Homebuilts with yokes not sticks?

    People who think yokes are for sissies are likely under 6'2". I'm a lot taller than that, and sticks are next to impossible. I hide the fact from a check ride or flight review cfi that I can't get full control movement without lifting up my leg from the rudder to avoid my leg in the way. I...
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    Crashes in the News - Thread

    The CVR is apparently usable. I hope this wasn't another EgyptAir 990.
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    Crashes in the News - Thread

    The ADS-b data s not granular enough to give more than a broad picture of average descent rates over the span of a few to several seconds...it would be less likely than more to capture data to show an impulse over a failure limit unless that cadence were in the single hertz range, most likely...
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    Crashes in the News - Thread

    One of the black boxes for MU5735 has been recovered. There is no indication of which box it is.
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    Crashes in the News - Thread

    350+ mph descent. 31,000 fpm. There are certainly too few facts to point to a cause. Yes, few would not at least suspect the trim system, or even the jack screw itself. Then there are the spar cracks. Then there is the possibility of deliberate action. Given how little info has been...
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    Crashes in the News - Thread

    Pictures. Highly identifiable sections of each wing shown in photos. The puzzle is there, though, for that reason. And if they had already failed (they were not evident in the videos), how would they have remained with the structure to impact (folded up). Recovery of the flight recorders...
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    Crashes in the News - Thread

    This is why I'm worried about either some sort of disastrous maintenance issue '(pickle fork'?) or something nefarious. The final moments appear to clearly show significant material being shed from the aircraft while descending. The videos do not seem to indicate the fuselage still had tail...
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