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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 ...


25

The most (kinetic) energy is in the fan and turbine blades and disc. The engine is enclosed in a containment chamber whose purpose it is to protect the rest of the airplane from shrapnel in case of a fan disc or fan blade failure. Here's a video of a test where a fan blade failure is simulated: As you can see, the fan blade ...


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 ...


14

The main place engine manufacturers will focus on minimizing damage is with the large fan at the front of a turbofan engine. FAA Advisory Circular 33-5 discusses the regulations that cover this. The manufacturer must show that the worst case blade rotating at the highest RPM can successfully be contained. Only 15 seconds after the event is the operator ...


10

Your concerns are reasonable and justified. A mid-air shutdown or reboot would be catastrophic to an airliner. Which is why, engineers designed the systems such that this scenario is practically impossible to happen. Electrical power An airliner has multiple electrical power source. Each jet engine has a built-in generator. When the turbine spins, ...


9

A jet engine may not contain a severe explosion (for whatever reason) but there are various mandated things that are put in place to help protect the airframe. The engines are generally mounted such that they shear off cleanly and away from the airframe. There are a few AC's like this one and this one that discuss how to deal with and comply with various ...


6

Cowlings can be designed to contain fan failures but if the core comes apart you have some pretty high velocity shrapnel coming out that nothing short of quarter inch armour plate will stop. The main design feature you typically see to mitigate burst risk is the placement of cable runs and hydraulic runs, where there are redundant runs, spaced apart in the ...


4

Turbine engines are spun up to idle speed using a starter. This is typically in the form of an electric motor for smaller turbine engines and APUs and pneumatic powered starters for large turbine engines. Once the gas core is spun up to a minimum speed, typically around 12-20% maximum core speed, fuel is introduced and ignited, causing a self sustaining ...


4

as somebody who did software tests on an unimportant (class D, will explain soon) system for an airplane to be approved to be landed on civilian airports: In airplane there is a strict hierarchy on what kind of software functions mean; they are listed in DO-178B. Class A systems are assumed to be "failure free"; they are extremely well tested. These ...


4

Occasionally a computer or smartphone will crash and reboot itself This can happen for two reasons: a software error or a hardware error. Both can cause the CPU to stop processing new instructions (i.e. a "hang") or to cause the machine to reboot itself. The latter is close to a hang, because the Operating System detects it cannot continue operating ...


3

it depends on what you call 'high-bypass'. The RB.211 engine was tested in a tail mount on a VC-10: For tail-mounted high-bypass engines, the engine mount gets long, which means it gets heavy. Tail- and bodymounted engines in general have drawbacks that also apply to high-bypass engines: the high position means maintenance access requires special ...


2

To generate thrust, engines need fuel and air: a spark will ignite fuel (by getting heat, above the ignition point), which burn with the oxygen in the air. On this (and other incidents), together with air, also rain (and hail or snow) in the engine, so the spark is not enough to ignite the fuel, and so the engines stop working. So, this is the important ...


2

It is simply the rate at which fuel can be burned. For instance, the Saturn V's first stage carried 1.37 million kg of liquid oxygen (along with the kerosene fuel), which it burned in about 165 seconds. Imagine the size of the jet intake you'd need for a comparable amount of air.


2

De-pairing means literally braking up pairs. In the case in question, it means that if an aircraft is equipped with engines of a certain specific type, one of the engines has to be replaced with a version that has been upgraded. The reason for the de-pairing is to mitigate the risk of a dual engine failure: Having two engines that are both affected by the ...


2

The nozzle position is automatically adjusted according to the current engine state to maintain optimal exit flow conditions at the end of the nozzle. The difference in nozzle actuation you are referring to is caused by a slight difference in activation time of the afterburner between the engines. Please see the following Aviation Stack Exchange question ...


1

Regarding power cycling specifically (as opposed to software-based failures in general which other answers have detailed very well), it's not a problem at all. Unlike a typical PC or smartphone which takes time to turn back on and can lose data when power is lost, the control systems on an airplane are typically designed such that they will resume complete ...


1

This photo show as the afterburner (left one ) literally just got ignite first one . So it is clearly to me the nozzles diameter is different ,one from another , (just for seconds)to ensure that the pressure of the gases exhaust is able to provide thrust. The left nozzle is opened more because the more mass of the burnt fuel left jet engine provide.To ...


1

Centrifugal compressors are limited by the size and sharp angle of the diffuser duct that has to straighten out the outward flowing air flow from the impeller compressor and reroute it back to the combustion chambers. This restricts the amount of air that can flow through this engine. Axial flow engines are straight through design and don't have this ...


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