Airplane Landing Questions -- How can the pilot see the ground?

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Any airplane mishap is investigated like crazy. It's not like with car accidents, where they only pay attention after dozens or hundreds of crashes. Any crash will be investigated thoroughly for months or years if necessary. The only reason that is practical is that there are so few accidents.
 
Klystron
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I disagree. Even in modern fighters, there are modes in the flight control that are called "autopilot modes".
Yes. My intended point was that autopilot functions can be modeled by distributed systems; modes of operation across a flight control grid connecting cluster . Not as a monolithic "on/off" device.
 
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jrmichler
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Air pressure can exert a huge force -
Stick your hand out the window of a car. Drive into a headwind at highway speed. Note the pressure when your hand is aligned with the airflow, and when your hand is perpendicular to the airflow. Compare the area of your hand to the area of a wing. Consider that aerodynamic forces are proportional to the square of the airspeed. Consider that your hand is not an airfoil.

Go to your nearest airport and pay for an introductory flying lesson. If it's in a single engine Cessna, ask for permission to open the window and stick your hand out. Single engine Cessna airplanes are allowed to fly with a window open, although it does get noisy.
 
jim hardy
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What formulas relate them.

how-airfoil-wing-makes-lift-png.png
Force = Pressure X Area
Look up "Wing Loading"
https://en.wikipedia.org/wiki/Wing_loading

http://www.thespacereview.com/article/1880/1
shuttle is about 120 pounds per square foot
not too different from a modern airliner

http://www2.gvsu.edu/ramseyea/B17.html
WW2 B17 bomber about 60,000 pounds / 1420 sq ft = ~42 pounds per square foot

little private airplanes around 15 pounds per sq ft

monarch butterfly about 1/30th pound per square foot
 

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CWatters
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Jump to 50 seconds of this video


You can see cracks forming in the fuselage (why does the crack formed and how often does it happen?) and the plane breaking apart in midair, so the passengers just fall down from the sky. If one wears a parachute, perhaps one can survive the fall?
It exploded at 35,000 feet and about 25 miles from nearest land. Even if you survived the explosion you would also have needed ..

Previous lessons in how to free fall.
An oxygen system.
A boat.
A waterproof GPS.
A waterproof satellite phone.
Or an emergency locator beacon.
 
jim hardy
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That China plane suffered a tail strike , that's where the tail drags the ground from a bad landing or takeoff.

PPRuNE talked about a 68 inch crack in underside of tail that was just patched over , might have failed depressurizing part of the plane and blew out a bulkhead.
I think that's what the official report concluded .
But i haven't read that report, just the thread at PPRuNE which is unofficial yet educational
 
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I'm starting to wonder if you are really serious here or are just messing with us - pretending to be panicky and irrational. Surely you know the Space Shuttle flies into space over a cluster of rocket engines, not from aerodynamic lift, right?

This thread needs to become more serious, rapidly, or it will be closed.
I was talking about the Space Shuttle landing, not take off. Remember it lands like an airplane and takes off like a rocket.

I'm serious because whenever I fly 2 hours short trips I always give reminders to family of important matters like codes to the safe, etc. just in case. And next year I plan to take longer flight (maybe 10 hours) to Europe I hadn't tried before. So just want to gain more knowledge of it (it is said that to treat phobia, you need to face the fear or study it more).

An airplane depends on continuous thrust or it could stall and fall down, whereas all other vehicles like cars or boats can be stop anytime and you are safely at ground.

I'm now convinced parachute is not needed because of difficulty of deployment. So just need to trust the best airliner. There is now this Airbus 380-800 model which has two levels. It needs much more thrust and jet engine, so the question now is.. is it better to fly using smaller airplane that requires smaller or fewer jet engine or bigger airliner with jumbo jet engines. Which do you prefer guys?

A380-800_white_thumb_943342d5-d150-4941-b217-ea38288ce48c.jpg
 

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An airplane depends on continuous thrust or it could stall and fall down,
If it lost total power, it would start gliding. It has a lot of time to get power again (except right at takeoff). Most commercial airplanes have several engines and can fly with fewer. The danger occurrences are few and far between. In fact, they are so rare that there will often be a TV show about any airplane crash like you are talking about. (Private airplanes are a different story. Those people are sometimes careless.)
 
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If it lost total power, it would start gliding. It has a lot of time to get power again (except right at takeoff). Most commercial airplanes have several engines and can fly with fewer. The danger occurrences are few and far between. In fact, they are so rare that there will often be a TV show about any airplane crash like you are talking about. (Private airplanes are a different story. Those people are sometimes careless.)
If the power won't come back. What model of airliners can actually glide all the way to ground? I watched this at movie once. This would be the safest?

I often ride budget airliner with only 1 engine at either side. So 2 engines at either side is better? What is the safest airliner model with many redundancies?
 
Klystron
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The airlines select aircraft to fly routes based on many factors -- expected number of passengers, expected cargo, amount of fuel required to fulfill the route, available craft at origin airport, etc. One can choose which airline to book even select which flight to book based on the expected airframe but ultimately route fulfillment lies with the airline.

Suggestions:
  1. Install a decent flight simulator on a computer. (select software based on your platform +cost).
  2. Take public tours of flight related operations including air shows, air fields, air traffic control centers, open houses; most free.
  3. Visit air & space museums. Engage the docents.
 
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FactChecker
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If the power won't come back. What model of airliners can actually glide all the way to ground?
They can all glide all the way to the ground (or water) Hahahaha! I crack myself up.
I often ride budget airliner with only 1 engine at either side. So 2 engines at either side is better?
One engine is all they need. Remember that they only need enough power to push it from a shallow glide to level flight. Turns would need to be slow and wide.
What is the safest airliner model with many redundancies?
Certainly, more engines improve safety, but two engines would improve safety so much that having more is not that much better.
 
russ_watters
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I'm serious....
Then you need to start being serious. You are saying way too much that is factually wrong or irrational. Being scared is fairly normal, but you're not in a plane, you're sitting behind a computer. You have time to think and not be scared.
I was talking about the Space Shuttle landing, not take off. Remember it lands like an airplane and takes off like a rocket....

An airplane depends on continuous thrust or it could stall and fall down...
1. The space shuttle's landing weight is 230,000 lb, not 3.3 million lb. That's closer to its takeoff weight.
2. The space shuttle lands without power; it glides.
I'm serious because whenever I fly 2 hours short trips I always give reminders to family of important matters like codes to the safe, etc. just in case.
If this fear is something that is causing you real problems, you should see a psychologist about it. All we can do here is correct your false beliefs of facts.
An airplane depends on continuous thrust or it could stall and fall down...
Technically, stalling can happen with or without thrust, but in either case, all airplanes carry spare engines so they can fly just fine if one fails.
It needs much more thrust and jet engine, so the question now is.. is it better to fly using smaller airplane that requires smaller or fewer jet engine or bigger airliner with jumbo jet engines. Which do you prefer guys?
Theoretically a plane with more engines should be safer in case of engine failure since it carries more extra engines, but from a practical standpoint airplanes are so safe I don't think that's been proven.
 
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The airlines select aircraft to fly routes based on many factors -- expected number of passengers, expected cargo, amount of fuel required to fulfill the route, available craft at origin airport, etc. One can choose which airline to book even select which flight to book based on the expected airframe but ultimately route fulfillment lies with the airline.

Suggestions:
  1. Install a decent flight simulator on a computer and learn to fly and land the sim properly (select software based on your platform +cost).
  2. Take public tours of flight related operations including air shows, air fields, air traffic control centers, NASA installations; most free.
  3. Visit air & space museums. Engage the docents.
What is the best flight simulator PC software available now that is accurate and doesn't require you to spend months learning the flight manual? Just want to have a feel of landing and the software should be accurate, not just for gaming.
 
russ_watters
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What is the best flight simulator PC software available now that is accurate and doesn't require you to spend months learning the flight manual? Just want to have a feel of landing and the software should be accurate, not just for gaming.
https://www.x-plane.com/

I believe you can install and use a working trial version of it...for 15 minutes of flight at a time.
 
FactChecker
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More knowledge is good, but there is a limit to the benefit. A serious fear of flying is like other phobias -- logic doesn't help a lot. I have a fear of spiders and will have to live with it forever. You may just have to resign yourself to accepting the dangers that everyone else does.
 
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They can all glide all the way to the ground (or water) Hahahaha! I crack myself up.
Hey. I just read the space shuttle can land by gliding only, can't a commercial plane do that too? I read

"As others mentioned, it was originally planned to possibly add small jet engines for use in assuring the landing, but after it was demonstrated that a good, trained pilot could consistently (with the on-board guidance computers help) bring it in for a glider-only approach in reasonable conditions, it was decided to not add the considerable weight of jet engines and their added systems, since every single extra pound of weight costs tens of thousands of dollars in added fuel requirements. The pilots practiced over and over and over (literally hundreds of landings if I recall) in specially modified Learjets (that simulated the rather unusually heavy and laggy aerodynamics of orbiters) until they could hit the landing every time.

In the end, seems to have worked…every shuttle orbiter (besides Columbia of course) has landed without any major hitch. If course, if they had been absurdly off course, they always had the option of bailing out with parachutes and ditching the craft.

The OMS engines were probably far too rough-tuned to use for landing, as pilots need to make very small and precise engine adjustments, but that's a guess."

One engine is all they need. Remember that they only need enough power to push it from a shallow glide to level flight. Turns would need to be slow and wide.Certainly, more engines improve safety, but two engines would improve safety so much that having more is not that much better.
 
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https://www.x-plane.com/

I believe you can install and use a working trial version of it...for 15 minutes of flight at a time.
When younger, I used the pc software MS flight simulator and F-15 Strike Eagle. I crashed the planes about a thousand times. So my other (learnt) concern is that if the airliner pilot is suicidal, he could easily crash the plane. So what kind of airliner has enough redundancies that any pilot can't just suddenly turn the engine off. Could you turn an airliner engine off by just removing a key, like in a car? or not?

By the way. Microsoft Flight Simulator is not better than X-plane?
 
Klystron
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When younger, I used the pc software MS flight simulator and F-15 Strike Eagle. I crashed the planes about a thousand times. So my other (learnt) concern is that if the airliner pilot is suicidal, he could easily crash the plane. So what kind of airliner has enough redundancies that any pilot can't just suddenly turn the engine off. Could you turn an airliner engine off by just removing a key, like in a car? or not?

By the way. Microsoft Flight Simulator is not better than X-plane?
As you have flown both sims, compare them and apply your criteria to decide.

[I'm ignoring the 'car key' question since by now you can likely answer yourself.]
 
russ_watters
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When younger, I used the pc software MS flight simulator and F-15 Strike Eagle. I crashed the planes about a thousand times.
I played both, and both are good. The F-15 simulator is pretty complicated for someone who doesn't know the basics though. If you try flying a Cessna, it is much easier than a jet (especially a fighter jet!). And this is where a "discovery flight" in a real plane would probably do you some good, as suggested earlier. You'll have an instructor take you up and then let you fly, and you'll see that the basics of keeping a plane flying are actually pretty easy.
So my other (learnt) concern is that if the airliner pilot is suicidal, he could easily crash the plane. So what kind of airliner has enough redundancies that any pilot can't just suddenly turn the engine off. Could you turn an airliner engine off by just removing a key, like in a car? or not?
Well sure, if a pilot wants to crash a plane, he can crash a plane. But that is obviously very rare.
By the way. Microsoft Flight Simulator is not better than X-plane?
MS Flight Simulator was discontinued 10 years ago. It may or may not have been discontinued due to the superiority of X-Pane at the time, but X-Plane at the time had the reputation of having better flight models.
 
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I played both, and both are good. The F-15 simulator is pretty complicated for someone who doesn't know the basics though. If you try flying a Cessna, it is much easier than a jet (especially a fighter jet!). And this is where a "discovery flight" in a real plane would probably do you some good, as suggested earlier. You'll have an instructor take you up and then let you fly, and you'll see that the basics of keeping a plane flying are actually pretty easy.

Well sure, if a pilot wants to crash a plane, he can crash a plane. But that is obviously very rare.

MS Flight Simulator was discontinued 10 years ago. It may or may not have been discontinued due to the superiority of X-Pane at the time, but X-Plane at the time had the reputation of having better flight models.
I'm downloading X-Plane trial now.

When I was using MS flight simulator before, and studying the flight manual for months, I was thinking whether in a real life emergency when the pilots were down. One could land a real plane? Note very importantly that I'm not asking now about landing a plane normally by just learning it from PC. But only asking in an *emergency*. I watched the movie Turbulence once when the actress could land the plane when the pilots got killed. So if you master X-plane. You could do that on an emergency? I know this is very unlikely scenario. But just asking.

The next two years, there will be a shutdown of the LHC, so planning a trip for the first time that would take 10 hours or more. So just want to be prepared psychologically. I heard one can think more clearly in Switzerland and can focus more on stuff beyond the standard model there. Perhaps it's the mood and weather that gives one the focus? Note many physicists love mountain climbing, like Lisa Randall. So mountains and physics seem to jive together.
 
FactChecker
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Hey. I just read the space shuttle can land by gliding only, can't a commercial plane do that too?
Yes, but it has to be high enough to be in range of a runway and be able to line up on the runway. (I am not considering any other type of landing, which have serious dangers.)

The main safety factor is having one engine running. That would allow a commercial airplane to fly to the nearest acceptable runway and land.
 
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Yes, but it has to be high enough to be in range of a runway and be able to line up on the runway. (I am not considering any other type of landing, which have serious dangers.)
When gliding airplanes without any fuel left (this can be done with any airplane from propeller based to jet engined?), do you use normal landing angle? or do you put the nose down? How to initiate gliding and how is the airfoil dynamics since thrust is losing fast?
 
CWatters
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I have flown in many aircraft types all over the world and have about 100 hours solo in gliders.

There are no simulators you can afford that will give you a realistic feeling of landing.

There are no aircraft (yet) that will prevent a determined pilot from deliberately crashing.
 
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When gliding airplanes without any fuel left (this can be done with any airplane from propeller based to jet engined?), do you use normal landing angle? or do you put the nose down? How to initiate gliding and how is the airfoil dynamics since thrust is losing fast?
Technicalities. I don't know much about that. A pilot can answer that. I know that the control surfaces should work and that the pilot would set the angle of attack for the maximum range. When he reaches the runway and is lined up correctly, it would be fairly routine and practiced. But the main thing about gliding is that it gives time to restart engines.
 
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Please watch before continuing. It will answer many of your fears.
 

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