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Recent content by Roga50

  1. Roga50

    AA jet and Military helicopter collide over Potomac

    The ATC recording that I heard has the helicopter pilot declaring at least twice that they are using "visual separation." FYI, Scott Manley ran a quick preliminary simulation of the flight along with ATC audio on his secondary channel:
  2. Roga50

    Miami Beach, Champlain Towers South apartment building collapse, Part 19

    South Florida fake engineer signed off on inspections of many recent projects--how soon before another collapse? https://www.local10.com/news/local/2024/11/12/safety-concerns-arise-after-south-florida-engineer-suspected-of-using-late-fathers-license/
  3. Roga50

    Boeing again

    If I were those two astronauts, you would NOT be getting me into Starliner for the return trip anymore. Even if Boeing and NASA agreed it was "safe."
  4. Roga50

    Lithium battery factory fire

    I still have a fixed automatic Halon extinguisher on my boat (in the engine room). Had no problem getting it re-certified a few months ago. They are still pretty common and the certification company said there is no reason to replace it unless it fails the tests.
  5. Roga50

    Baltimore Bridge collapse after ship collision

    New Chief Makoi video on bus tie breakers.... Link
  6. Roga50

    Baltimore Bridge collapse after ship collision

    I think it was Chief Makoi who even spoke about changing fuel types in a video a while back. It is not an instantaneous switch--you have to do it gradually (meaning the fuels are mixed during the process), so it takes a while to complete. There is an (old) Kongsberg MC90-V engine room...
  7. Roga50

    Baltimore Bridge collapse after ship collision

    I think the issue here that may have been missed by the automation is that DG3/4 fuel pump (and probably also cooling pumps, at least per the simulators I've been looking at) would not have been powered by the 6600v bus. So when those pumps lost power, the automation SHOULD (if I had designed...
  8. Roga50

    Baltimore Bridge collapse after ship collision

    I was waiting for Chief Makoi's video... He's great at explaining these things. So based on his video plus some comments that his viewers made (and he responded to), I'm thinking: Some sort of fault occurred in TR1 (I speculated on this before), leading to LR1 and HR1 opening. In the...
  9. Roga50

    Baltimore Bridge collapse after ship collision

    I had forgotten about the possibility of the bus tie opening up, splitting the transformers between two separate sources.... (it was late/I was tired....) But, I would also assume that the ship's automation could handle a situation where if the bus tie opened, it could simultaneously trip...
  10. Roga50

    Baltimore Bridge collapse after ship collision

    In playing with the various simulators I posted about a while up on the thread, even before the accident, I had noticed that on the ships that had redundant transformers just like this one, there was an interlock on all of them so that both transformers could not be connected at the same time...
  11. Roga50

    Baltimore Bridge collapse after ship collision

    Seems like all roads lead to some sort of fault at TR1 or it's breakers. When they restored TR1's breakers, the second fault tripped the DG breakers instead (was the fault so large that TR1's breakers didn't even get the chance to trip the 2nd time?) The fact that TR1 was not in use until...
  12. Roga50

    Baltimore Bridge collapse after ship collision

    FYI, for those who are interested, there is a Chinese (I know, might not be the best source, obviously download at your own risk) ship simulator/trainer that one can install and experiment with, located here: http://www.ers3d.com/home/index.do It is free for some of the ship models, but...
  13. Roga50

    Alaska Airlines flight forced to make an emergency landing...

    From the looks of the above diagram plus the picture of the location of the loose bolts found on the United jet, if the bolts fell out of the bottom hinges, that would effectively detach the springs from pushing the plug down into the upper guide fitting. Without that spring tension, a jolt...
  14. Roga50

    Tesla's giant 'recall'...

    Push button shifting... Isn't that the thing that killed Anton Yelchin (in a Jeep Grand Cherokee)? https://en.wikipedia.org/wiki/Anton_Yelchin#:~:text=Original%20Series.-,Lawsuit%20and%20recalls,-%5Bedit%5D I think it was determined that the shifting was confusing and dangerous and you could...
  15. Roga50

    We've had murder cars, now we've got murder-trains in Florida of course

    This is near me. Trains are not that unusual in South Florida. In fact they are very common. But brightline is a lot faster than any other trains we have here. And until Brightline, these tracks were used mostly for relatively slow freight trains (and in fact, they still are in addition to...

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