6 ms·

As an armchair engineer, I wonder about engine behavior at high angle of attack. It looks like it could be difficult to feed the engines enough air to maintain

• dghughes 6y ago
  > As I recall, one of the factors in abandoning the idea for passenger planes Another was the different forces on passengers depending on where you were seated. A regular airplane everyone is situated on the same plane (ha pun!) more or less. But on a V config anyone far from the center would experience greater forces when the aircraft moved.
  • axaxs 6y ago
    That's what I was thinking. I've been on a lot of planes that banked -hard- on approach. I can't begin to imagine what that would feel like sitting in this configuration.
    • blunte 6y ago
      Presumably the roll rate on that type of plane would be lower than on a traditional tube-with-wings design. So while the bank angle might still be high, it won't happen quickly. As long as the plane is banked at an appropriate angle (relative to the rudder angle), the passengers shouldn't feel anything other than perhaps a bit more positive G force.
      • axaxs 6y ago
        What about turbulence? I've been in some doozies where it felt like the pilot was fighting it hard, constant up and down and left and right corrections. I wonder what effect that fast change in altitude has, if any? Just G Force?
        • ncmncm 6y ago
          Pilots do not fight turbulence, hard or lightly. The plane goes where it is pushed, and you go with it. A very long (thus widespread) updraft might cause the pilot to reduce power, but that is very rare.
          • axaxs 6y ago
            I'm not refuting you, but now I'm genuinely curious. We all know or think of turbulence like hitting bumps in the road, shaking, etc.. I was on a shorthaul, some embraer or similar sized plane, and experienced this only once. We kept hitting those big 'bumps', then I'd feel the plane dive down or up quickly. The kind that gives you the feeling in your stomach, like going over a hill as a kid in a car. In my head to this day I assumed the pilot was quickly trying to find an elevation to avoid the turbulence, but your comment implies that's incorrect. So those quick pitches are also a form of turbulence? It was stomach turning, and honestly made me a bit uneasy.
            • ncmncm 6y ago
              What you call turbulence is really just a mass of air moving at a different speed or in a different direction, and the plane moved out of one into the next. So, e.g., the plane passes into a downdraft near a cloud, and then into an updraft under the cloud, then into another downdraft, and then out. You feel four lurches. The pilot might be looking for a path that stays away from those, but you won't feel anything the pilot does.
        • blunte 6y ago
          Turbulence that would push an aircraft up or down will have the same effect on either design. However, turbulence that would typically cause a plane to roll quickly (such as hitting some sort of vortex or wake from another plane) should have less effect on a plane with a more widely distributed mass. On the other hand, once you start the big V plane rotating, it will be harder to stop rotating (take longer, unless the rotation energy is so great that the comparatively short wings simply cannot compensate). We are at the point of fly-by-wire where there is usually a computer between the human and the control surfaces. This enables truly unstable aircraft (like the awesome F117 stealth fighter) to fly when they are inherently unstable designs. But as evidenced by the 737 Max debacle and the long ago A320 (320?) issue, sometimes the computer makes an unfortunately poor decision and does a bad thing. Point is, we are already there, so we might as well allow the computer to make a V fly wonderfully and save a lot of fuel and cabin noise.
  • mrfusion 6y ago
    I wonder why the flight plan couldn’t take this into account? Start turning sooner, etc. Or make an announcement before starting manuevers. Have a place people could move into. Just spitballing.
    • p_l 6y ago
      The thing is, you don't design for the flight plan - you design for the "oh my god there's super strong crosswind, complex approach, and we have no fuel left for another airfield" and similar cases.
  • jacknews 6y ago
    That shouldn't be an issue for cargo planes though.
    • valuearb 6y ago
      Ever hear of cargo shift? These would subject cargo to far higher g forces, making it much more likely cargo could move and unbalance the plane. Google 747 crash Iraq for the most spectacular example of this happening in real life.
      • dehrmann 6y ago
        Yikes, but "unbalancing" was only part of the problem: Guessing you're referencing National Airlines Flight 102 > ...improperly secured cargo broke free during the take-off and rolled to the back of the cargo hold, crashing through the rear pressure bulkhead and disabling the rear flight control systems. This rendered the aircraft uncontrollable, making recovery from a stall brought on by a change of balance from the shifted cargo impossible. Also > the cargo of five mine resistant ambush protected vehicles (three Cougars and two Oshkosh M-ATV's), totaling 80 tons of weight, had not been properly secured. That's serious cargo.
        • inetsee 6y ago
          I would have hated being in that bus driving towards the crash site. https://www.youtube.com/watch?v=7sUWC2jfjqI https://www.youtube.com/watch?v=7sUWC2jfjqI
        • valuearb 6y ago
          I did not know it broke through the pressure bulkhead, like I said it’s an extreme example. In the case of this plane design I think you’d see a lot of much smaller cargo shifting incidents, where banking one direction or another caused packages or their contents to shift to one direction. This could cause a more subtle change in center of gravity, that the pilot may counteract at first, but leads to further shifting or an unrelated problem that causes an accident.
      • 6y ago