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122

The runway ahead of you is useful to accelerate and - if needed - to decelerate. If you enter (or touch down) the runway in the middle, you will not be able to benefit from the part of the runway behind your entering point. It is the same as if that part would not exist. Therefore it is useless.


111

Because ditching is extremely, extremely rare, so the costs of redesigning aircraft along with the extra drag and weight (increased fuel burn) it would no doubt add to the airframe far outweighs the potential benefits. That argument might sound weird to someone, but think about it this way: would it seem reasonable to redesign every single car on the planet ...


66

I'm a programmer and private pilot, so maybe I can help dispel some of those fears. The computers that run a commercial airplane are conceptually much simpler than the one that runs your phone. This means far less chance of a bug in the software, just because there's less for the programmer to keep track of. If your phone restarts, it doesn't imperil ...


55

MCAS doesn't have its own on/off switch It is a fly-by-wire feature designed to account for a particular flight regime that would not (or was not expected to) be encountered very often in normal operations, and is intended to account for some of the aerodynamic effects of the LEAP-1B (CFM International) engine installation for this model. Its activation ...


53

The 737-800 is not grounded (and never has been). The aircraft type has an excellent safety record. Since 1997 over 5000 have been produced. The 737 MAX 8 is its successor. The aircraft is very similar to the 737-800. One of the differences is the placement (more forward and higher) of the slightly bigger engines. This changed the stability of the aircraft ...


53

In the US they do very similar theater when a pilot needs to relieve himself. There is an announcement that nobody is allowed to come forward, and grim looking flight attendants are blocking the aisles with coffee trolleys. The details surely depend on the airline. Each of these procedures goes back to some bad incident. The cockpit doors are locked since 9/...


49

There is a general design principle, that some, but not all, of the behavior of the flight guidance system or autopilot should be visible to the pilot. Usually automatic engagement or disengagement of a control system is indicated, but sub-modes of these controls or manual changes might be unindicated. That sounds simple and logical, but in reality it's a ...


47

Not only is it possible but it happens. This is formally called a "runway incursion" and it does happen like 2005 Logan Airport runway incursion or the B733 / vehicle, Amsterdam Netherlands, 2010. Skybrary has a full list you can find here which is quite lengthy and includes a full section for Vehicle Incursion.


46

When you fly gliders you discover it's quite common to run into air that's descending at 1-200 fpm, or "sink" in soaring-talk. Descending air next to a thermal, or air descending due to downsloping terrain. It's a lot more than that at times, but a couple hundred fpm is typical. On a day where there's any convection (with rising air, there is always ...


38

I'm not sure that comparing car seatbelts to airplane seatbelts is that useful here. The acceleration involved in a car crash at highway speeds are much greater than even the acceleration, mostly vertical, involved in even severe turbulence. For example, after a 2015 severe turbulence encounter, investigators determined: "In the first event, the peak ...


38

Something should be pointed out here. Fume events are not related to Phosphate Ester hydraulic fluid and there is nearly zero risk of Skydrol or Hyjet getting into an air conditioning system (if there are airliners out there that use air conditioning source bleed, to pressurize accumulators or reservoirs, with an open return path back through the bleed ...


36

Note: This does not take travel to/from the airport into account. The Wikipedia page on aviation safety has a nice table with deaths per journey, time and distance (based on data from the UK between 1990 and 2000): Car: 40 deaths per billion journeys, 3.1 deaths per billion km Aircraft: 117 deaths per billion journeys, 0.05 deaths per billion km Assuming ...


34

A start on a TF all the way to idle is about 20-40 seconds depending on the engine, and the fan itself won't do more than creep a bit until the core actually lights off which is 5-10 seconds, so they'll have lots of time to get down and get away as per @ymb1's diagram, once the wheeEEEEEEEEEEtickticktickticktickticktick starts.


33

(Airbus) The suck zone ahead of a CFM56 on an A320 is less than 5 meters. The couple have enough time to take a leisurely walk toward the cockpit window. The engine start time takes upwards of a minute (the starter is limited to four 2-minute bursts, followed by a 15 min cool down). Newer engines take longer to start. On the neo with PW1000G engines it's ...


32

Other answers have addressed the case of weather that's too bad for flights to operate, but another situation that can occur is congestion. Take a look at the Average Arrival Rate chart for San Francisco International Airport (SFO) (more details on this in this blog post by an airline dispatcher). During visual conditions with favorable winds, they can ...


31

The problem with a severe peanut allergy is that you don't have to eat a peanut to be affected. With a severe enough allergy, inhaling peanut "dust" can trigger a life-threatening emergency. In a confined space, any number of events could cause an issue: people dumping peanuts into their hands, dusting their hands off, accidentally sneezing while chewing ...


31

On top of the previous good answers, I would like to add that the aerospace industry does take ditching seriously. 14CFR Part 25 and regulations from other agencies require that transport category aircraft be designed such that the occupants have a reasonable chance of surviving a water landing. This means that, in addition to providing life rafts and life ...


31

There is another scenario other than "line up and wait" that the other two answers cover... A "flight" of more than one aircraft may be cleared as a group to take-off. This can consist of many aircraft sharing the runway during take-off (and even landing). So you can have multiple aircraft on the runway when: A "line up and wait" order is issued to line ...


30

Yes learn both, but... not at the same time. As Dave says, there are too many differences to be absorbing simultaneously. It's like a new airline pilot taking a type course on a Dash 8 and an RJ at the same time. It'll burn you out. If all this is a hobby activity in the first place with no urgent time lines, drop the power training for now and go take a ...


29

It refers to takeoff from an intersection rather than using the full runway length. The part of the runway behind you is now useless. It is part of the saying because the TODA (takeoff distance available) is now reduced and this needs to be taken into account when doing performance calculations. It is e.g. discussed in this thread on pprune.org. One could ...


28

All turbine-powered aircraft used in scheduled airline service under CFR Part 121 are required to have an approved TAWS installed; §121.354 Terrain awareness and warning system. (a) Airplanes manufactured after March 29, 2002. No person may operate a turbine- powered airplane unless that airplane is equipped with an approved terrain ...


28

The short answer is that we want to warn the pilots about an impending stall well prior to an actual stall condition. From a safety perspective, waiting until the airflow starts to separate, or at the onset of buffeting, it's already too late. By using AOA we can set a very conservative threshold. This AOA threshold can be adjusted by taking into account ...


28

Funeral homes sell gum bags for ashes. They dissolve in the ocean, releasing the ashes. You could make satchels and drop them in bundles with the teeth wrapped in kelp.


28

The props are done before starting because you need to make sure the blades and spinners are fully cleaned off while they are stationary. Otherwise, they'd vibrate like hell when starting and shed bits of ice all over. Also, if you just sprayed the props while running the engines would ingest a lot of glycol, which, if it doesn't make the engine flame out, ...


27

I wear earplugs all the time flying in both pressurized and unpressurized environments, and have done it for many years. Air pressure changes have no noticeable effect when wearing foam earplugs as the interface between the foam and ear canal is not totally air tight. The silicone flanged ones made for airline flying have a tiny bleed hole in them (...


25

This is standard procedure when a pilot needs to use the lavatory (bathroom). The area near the front lavatory is blocked off by cabin crew, so you cannot get into this area. The pilot unlocks the cockpit door, steps out, and goes into the lav. a cabin crew member takes his place, and the cockpit door is closed. reverse steps 1-3. Why step 1? To ...


25

Cloud, you are making a huge inference from a few small data points. But in any case, to the basic question, which is actually a very good one: In terms of the chance of getting killed, (what you seem to be looking for), maybe, marginally, but not enough to rule out operating from grass. If you know what you are doing, and make allowances, I would say ...


24

Before we start, it's important to say that your concern is not irrational. If this were to happen, or if your plane's control systems were to otherwise malfunction in a dangerous manner, your life would genuinely be in danger. You aren't the first person to have thought of this, though. For this reason, we have a category of control systems we describe ...


23

In 1978 a B737 aborted a landing due to a snow plow on the runway. The aircraft crashed during the go around because one thrust reverser did not stow properly. https://en.wikipedia.org/wiki/Pacific_Western_Airlines_Flight_314


23

Skydrol was developed to provide a hydraulic fluid that does not catch fire when a fine mist of particles under pressure is released, upon a leak in the hydraulic system. Of the two evils, poisoning or burning, a case can be made to avoid the latter when considering aeroplanes. For ground based systems like full flight simulators, hydraulic systems are on ...


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