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About monophonic

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  1. Thoughts on one of the older ways of rocketry: composite tanks inside a metal hull? How about a definitely counter-intuitive variant: metal hull-tank walls with composite bulkheads?
  2. The opposite does not follow either. If profit culture wasn't so prevalent no-one would have ever been fired for raising concerns about safety issues. Yet that has happened repeatedly. People can do extraordinarily stupid things if they are pushed for results. I wouldn't believe anyone would have done such a thing again after SK751, but am certain that I do not know it. NASA can't leave astronauts lives hanging on beliefs and thinkings, they have to do better than that. They need to know. Of course political pressure has been mentioned, but all that means is even weaker arguments suffice for an excuse to conduct an investigation. Not even Boeing gets unanimous love in the senate. Maybe a couple of senators threw a bet over which of their respective pet companies does safety better? Should we have waited for a final report on Mr. Musk's smoking habits before taking that up too? I did mention they were allegations didn't I? It doesn't look as bad if the omission was only in the differences training material. Then again what point does a "differences training" serve if it doesn't train one on all the differences? Luckily there are smarter people than I looking into that. Oh and just to make one thing clear I wouldn't cancel a flight for getting scheduled on a 737MAX.
  3. Yes, they share the same corporate leadership. Ergo they potentially share corporate culture including corporate safety culture. Therefore potential safety concerns at Boeing's aviation side can be a reason to do an audit of the safety culture at their space side. You are right in that NASA does not have to concern themselves with actually inspecting the aviation side. As long as things are known to be fine in the space side of Boeing, it would not matter for Commercial Crew if 737s were dropping like flies... Plus FAA will be doing a number on the aviation side anyway if the allegations are found to be true. Of absolutely no relevance to the allegations raised. Whether a design is a derivative or a cleansheet one it is not a factor in choosing what to include in the operating manuals. None. Cancelling CC would leave Orion the only crew bus in the west. Thus Orion would have to be integrated to other launchers because SLS cannot provide the launch cadence to support the ISS. Then credibility of SLS' published reason of existence would get compromised. The rest is politics and thus out of bounds on this forum.
  4. Wait? Three pages about Musk and safety in general? But no-one has mentioned even in passing that the other company under scrutiny has recently been implicated in omitting safety critical information from the operating manuals of a flagship product? And that has possibly contributed in a loss of passenger lives event? Of course the investigation is still very much ongoing so the officials cannot openly mention it - just as they cannot openly mention the other one's substance use habits. Just reminds us that there are more than one side in a coin.
  5. Decoys are physical things, although they do belong under the broader concept of jamming. What you have been describing is better categorized into deceptive jamming techniques. Have you considered how your technique behaves in non-trivial acoustic environments e.g. surface duct or bottom bounce conditions? And especially when some emitters are in a different region from others? (a quick reference of sound paths for those who want one: )
  6. "The constantly-changing acronym" would fit in the Culture names theme SpaceX has had going with the barges pretty well. I like that! Because when they do... third reich.
  7. These guys might be interested in cheaper bricks. Most 3D printing building systems seem to extrude concrete like materials though.
  8. Do we know that that part is bent and not extruded? Also should one want to tap a thread in the hole wouldn't that have to be done after painting? Otherwise paint would clog the thread right?
  9. I wouldn't jump quite that far just yet... First, pilot holes are a standard drilling technique. That is, you first drill a smaller (pilot) hole that is easier to get in exactly the right (or wrong as the case may be) spot which then helps keep the bigger drill bit at the right spot. Second, if you start a hole and stop (for example because you realised you are drilling it at a very wrong spot) before the tapered point of the bit is entirely inside the material being drilled you end up with a hole smaller than the bit you had. In thin materials that can even be a nice through hole, albeit one with a tapered edge (like you would want for counter-sinking a screw head). So even though no 2mm holes are needed that does not prove at all that 2mm holes are not drilled in manufacturing. I may just be that any of that size are to be immediately enlarged to a required size. Or it happened as a consequence of abortive misplaced drilling attempt. Also who would benefit from sabotaging a Soyuz?
  10. Maybe there is a second hole across the room from the now patched one?
  11. Add noisiness to that mix and you are getting close. Active noise cancellation and other advances mean flow noise now dominates over machinery noise. Exact priorities over each other depend on the class; a bomber values maximal silence over all others while an attack boat needs to be fast enough to be useful.
  12. 100 pax is regional airliner size. They are typically boarded and unboarded through a single, narrow one person at a time sized door. This happens in a reasonable time thousands of times every day. That access arm will not be the limiting factor for boarding time regardless of the destination and attire (casual or space suit).
  13. From pocket change to small country budgets. Cheap end can be say a smartphone on an ocular holder and a small scope on a motorized mount. Fancy coordinate seeking scope mounts, specialized cameras and powerful computers for processing can be as expensive as you can imagine and more. This is doable at every price level.
  14. And that, kids, is why you must be very careful with how you use quotation marks.