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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 ...


56

You can find the full incident report here and this topic is touched upon briefly, but in short they had little to no time to entertain any other options but a full speed landing. It was not until the aircraft [was] on the final descent for landing that the Commander realised they could not reduce the thrust on the number 1 engine. The speed was not ...


55

Yep, the critical commands are repeated 3 times. This ensures there is ABSOLUTELY zero doubt in anyone's mind (especially on a big crew airplane) of what needs to be done in a critical situation. It also standardizes these criticalities across different aircraft and aircrew cultures. "Bail out, bail out, bail out" "Eject, eject, eject" "Abort abort ...


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 ...


54

Engine #2 wasn't doing its job either Had the situation just been engine #1 stuck at high thrust, with engine 2 normally controllable, than what you describe would be a reasonable response to the situation. However, that was not the case with CX780 -- during approach, Engine #2 was stuck at 17% N1 (or rather below idle) and thus delivering effectively nil ...


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/...


48

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 ...


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 ...


43

No They do not continue this practice anymore. This is likely because landing gear are more reliable now than they were in the 70's. There is also the practice of Air Traffic Control prompting military pilots to check their gear is down, by verbally adding "Check Gear Down" to their landing clearance. Source: Checked in with some of the Air Force / Air ...


39

I don't know where he gets that. Regulation wise there's nothing stopping an airline pilot from listening to music as long as he/she can hear ambient sounds or communications and modern headsets make it easy to link an ipod to headphones that are also receiving the comms. Pilots are allowed to take naps in flight as long as they are awake within 45 min of ...


38

Procedure calls for the mayday distress signal to be said three times in a row so that it won't be mistaken for another word or phrase that sounds similar under noisy conditions. The use of Mayday dates back to 1923 when it was first used because it sounded like the French word m'aider, which means “Help me." In those early days of radio it was necessary to ...


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 ...


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

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

One of the more common causes of crash and fatality is a low altitude stall-spin. A spin, in a modern aircraft, isn't of itself deadly -- with many designs, all you have to do it let go of the controls, and the aircraft will unstall and let you simply fly out of the resulting spiral dive (if you don't wait too long and go past Vne, anyway). If you get into ...


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 ...


30

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 ...


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

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

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 ...


26

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 ...


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 ...


23

It's very likely that the 787 would have less problems with turbulence than the DC-8 did. The wings of the Boeing 787 are more flexible than the DC-8, and that flexibility will damp the immediate impact of turbulence. More important, the Boeing 787 has a gust alleviation system that reacts to turbulence by counteracting the induced accelerations using the ...


22

From the incident report section 1.1.4: a. At 0519 hrs during the descent to a cleared level of FL230, ECAM messages “ENG 1 CTL SYS FAULT” and “ENG 2 STALL” were annunciated within a short period of time. According to the Commander, a light “pop” sound was heard and some “ozone” and “burning” smell was detected shortly before the ECAM message “ENG ...


22

My grandson has a severe peanut allergy. The Doctor has emphasized that this allergy can be fatal if the kid gets a very small dose of peanut, without very prompt treatment! The common first aid treatment is an injection commonly administered by an EpiPen (or similar) so the EpiPen must be available on very quick notice 24/7. What many people don't ...


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