At the gym today, on all the TVs, the media talking heads were crucifying the FAA for being "unsafe" or playing fast and loose with passenger safety (for not grounding the planes). I've always held the FAA in high regard, and think they do a good job. Are they really being negligent here? Or is the media just looking for something to spark outrage? Can anyone with more specific knowledge of aircraft safety weigh in?
Two crashes in 6 months and there's only 350 planes in existence is a pretty bad safety record that is probably on par with Tupolev. The US can tacitly blame "third world" pilots all they want, but with 300 people dead already, I think it's important for the FAA and Boeing to say exactly what is going on, especially since the planes are in use in the USA. There is a debate over if the plane's hardware, software, or p…
You're picturing a fighter jet or something with severely swept wings. Do an image search - 737s, 747s, et al do indeed have gently swept back wings. They don't stick straight out at 90 degrees like aircraft from the piston era.
Ohh I see, okay thanks.
I like the LAX screensaver on Apple TVs—you can pick out the more organic/bird-like curve of the newer generation carbon fiber 787 planes from the old ones. I’ve never thought about it, but they do look less stable.
I urge people to read the discussion by pilots regarding the 737 MAX. https://www.airlinepilotforums.com/safety/120514-ethiopian-7... It all comes down to this: "There are far too many aerodynamic bandaids that are permitted to pass the current standards. Not just this particular airplane, but a whole bunch of airframes. If the basic aerodynamics won't pass without the pushers, pullers and now AOA induced changes to…
It's a bit more complicated than that even. The 737 was originally designed for a very different mission than it's being used for right now. If you find pictures of the original 737-200s they look very different from the MAX line of today. It was built in an era when it was assumed that 707 and soon after 747 class airliners would serve the hubs and then smaller 737s would serve the small regional airports. As such t…
> the ovoid engine inlets
The original design of the 737 did not have ovoid inlets.
You can see regular circular nacelle inlets on the 737-100:
It's a bit more complicated than that even. The 737 was originally designed for a very different mission than it's being used for right now. If you find pictures of the original 737-200s they look very different from the MAX line of today. It was built in an era when it was assumed that 707 and soon after 747 class airliners would serve the hubs and then smaller 737s would serve the small regional airports. As such t…
> the ovoid engine inlets The original design of the 737 did not have ovoid inlets. You can see regular circular nacelle inlets on the 737-100: https://secure.boeingimages.com/archive/Boeing-737-100-2JRSX... and on the 737-200 here: https://secure.boeingimages.com/Assets/V2/jrZYYwCXohU1rDmk4e... The ovoid inlet design was introduced with the 737-300, when the engine was changed to the CFM56.
The ovoid engines were a result of high bypass engines being added on the 300. The low bypass turbines on the older models was much smaller. These were then removed on the max because the engine was mounted higher and further forward on a low profile pylon.
I agree, in my eyes it is debate between "the plane is not safe to fly by anyone" and "the plane is safe to fly with additional training, when given" If the 737 MAX planes remain in the air in the USA, Boeing and US Govt are de facto saying "third world pilots clearly just don't understand how to fly our planes". If they ground the planes, they de facto admit there is an actual safety issue.
> "the plane is safe to fly with additional training, when given" If that is ultimately the conclusion, then it still gives the FAA and EASA a black eye, since they allowed the aircraft update without additional training for MCAS. Best case scenario for Boeing is that the Ethiopian Airlines crash turns out to be something else. If it is MCAS related Boeing, the FAA, and EASA amongst others that green-lit the update w…
You just can't have more data points, because flight travel is too safe. And no, the FAA is not really that good, general aviation pilots die all the time from negligence and the FAA doesn't enforce the rules when pilots violate them (in particular low altitude flying).
What’s the “low altitude flying” rule that isn’t being enforced?
14 CFR 91.119
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface.
The FAA has always been very pro-active about grounding planes that are unsafe. The airlines operating these aircraft do not benefit by continuing to fly them if they are un-safe. Between the cost of the loss, public image etc. it would not make economic sense. Given the trade tensions the US has with both China and the EU and the fact that both are offering competing products (Airbus more so), this sounds like more…
To me the more political move seems to be the FAA not grounding them... 2 brand new planes yoyoing after take-off and crashing...
It's a bit more complicated than that even. The 737 was originally designed for a very different mission than it's being used for right now. If you find pictures of the original 737-200s they look very different from the MAX line of today. It was built in an era when it was assumed that 707 and soon after 747 class airliners would serve the hubs and then smaller 737s would serve the small regional airports. As such t…
Are you saying that the lack of proper response to changed requirements is the primary source of 737MAX's issues?
Maybe? Let me leave you with one other tidbit though. Beyond the requirements, airframe changes, and added electrical stuff, to fly the 737s you need a type rating and that rating is basically an education on all systems and procedures for the airframe. Boeing worked hard to make all aircraft from the 200 through the MAX fall under one type rating so if you get certified to fly an old low bypass 200, you can hop out, walk across the tarmac to a MAX and take off with another load of passengers. Obviously almost nobody runs the 200 anymore but the later aircraft are all still operated in some capacity and having one rating to rule them all makes it cheaper for small operators with mixed fleets to afford the training costs. In doing this, Boeing had to make the basic "UI" for the aircraft all the same, regardless of model. I'm not typed in the 737 but from what I've heard, it's resulted in a lot of user flow and documentation idiosyncrasies, particularly in the MAX lineup which could be part of the issue here. All that said, the trim motor disconnectors have been in the same place for most of the aircraft's history I'm told and hitting them would have likely prevented the Lion Air accident.
I like the LAX screensaver on Apple TVs—you can pick out the more organic/bird-like curve of the newer generation carbon fiber 787 planes from the old ones. I’ve never thought about it, but they do look less stable.
From a stability perspective there's likely no difference insofar as the stall response will be bad regardless. You can have complex wing geometry that stalls gracefully, for instance carbon general aviation aircraft have similar traits but require much cleaner stall response for certification generally.
BTW since it's been tossed around a lot, good stall response is when the whole wing stalls at the same time and both wings tend to stall together, therefore you get a clean lurch downward in a straight predictable line. Bad stall response is one part of one wing stalling before the rest such that the wing drops and the plane has to be fought to avoid a spin or if extreme enough, a tail slide or extreme side slip.
Trump tweeted that planes have become too complicated and that the old and simple form is much better. His tweet sounds dumb but there is some truth in it. As you say, planes and procedures have become very complicated. And I think there are only two options: making planes simple again which make them less efficient or let computers fly the plane and make the interface simple(r). If you look at the rockets of SpaceX…
> His tweet sounds dumb but there is some truth in it. There really isn't. Automation is part of what has made flying safer over the years. Also, compare the cockpit of an Airbus with e.g. an old B737, the 300 series for instance. The Airbus cockpit is much simpler, in the sense that there are less gauges and knobs for the pilots to be concerned about. Automation has, over all, made things simpler and safer.
