103

Just because aviation developers use Python, does not mean that Python actually goes flying. Lots of aviation development is about testing, stressing, validating, analyzing, and documenting the code that does go flying. Python is an excellent language for all that validation work, even though it stays on the ground.


75

The big disadvantage here is the loss of precision due to the high compressibility of gas compared to liquid. Because gases are highly compressible, they provide a buffer to changes in pressure commanded by the operator to move the piston in the cylinder. That poses two problems; first, it means that the pneumatic cylinder doesn't respond instantly to ...


61

There are three different ways that aircraft can give internet access to its passengers, which will most likely be on at around 38,000 feet. First off, to have Inflight wifi, there needs to be a ground-based internet server, a transmitting dish, or a satellite dish. There must also be a receiving and transmitting antenna on the aircraft and an onboard server ...


55

(airliners.net) Above I marked five similar plus signs on the 737 (there are more). Beneath the +'s are the contacts for the backlighting of each panel. If it acts up then pressing on the sign will ground/secure the connection and may solve the issue. The electroluminescent light-panels are flexible and the ride can be too bumpy sometimes. Better push the ...


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 ...


48

Audible Warning On light aircraft there is a reed (much like used on a musical wind instrument) mounted on one wing root, which is angled such that at the Angle of Attack which would cause a stall, the reed "plays" which can be heard in the cockpit. Here is a view of where this system is mounted on a Cessna: (source: weekendcfii.com) On some aircraft, ...


47

If you look closely at your drawing you will see the cables are not really simple pull cables but really act like steel belts. That is, there is a pulley at each end and when you actuate the control the cable is rotated around the system in a loop. The end pulleys and or idler pulleys are spring loaded to maintain a predefined tension on the cables and ...


47

It isn't true, not as an indictment of the simulator software community as a whole anyway. It may be that your pilot friend doesn't have experience with modern simulators, let's take X-Plane for example... X-Plane has a "professional use" version, which is simply the regular X-Plane with a commercial license and a few extra features. The underlying software ...


45

My short answer: Stability is reduced by shifting the center of gravity aft. Shifting it past the neutral point makes the airplane unstable, so movements away from the trimmed state are accelerated. This increases maneuverability. Flight computers are multiple redundant, if one dies the others take over. Slow unstable airplanes can be flown by a human pilot,...


40

None of the avionics systems I've worked on have used Linux or any consumer-type operating system. There are a few main issues. First is the practical. Most safety-critical avionics involve a control loop and thus have a real-time requirement. That means it's not just important to run a process and get an answer, you need to get the answer within a ...


38

The small bulb houses the antenna that provides the satellite communications for the internet link. Inside the aircraft several wireless access points provide a WIFI signal to the passenger's equipment. The wireless access points are connected to a central modem which in turn is connected to the transceiver unit. The transceiver uses the rooftop antenna to ...


38

No it does not, it does not need one, there is a mechanical connection to the flight controls that can be used if all else fails. The B737 flight controls are hydraulically powered. There are three hydraulic systems: System A, System B, and Standby. Only one main system (A or B) is required for hydraulically flying the aircraft, during normal operation they ...


37

Here's a better picture showing all probes, and labeled: Link to original, high-resolution, unnumbered picture They are: Ice detector Multi-function probe 1 Static port TAT probe Side-slip vane Pitot probe Angle-of-attack vane Airbus.com has a PDF (pdf page 125) about the various probes. 1 As the name suggests, the multi-function probes record different ...


35

The simple fact is that an unintended gear deployment could be catastrophic, as it has a profound impact on the flight dynamics of the aircraft (one of the reasons there are warnings for both retraction and extension). The benefits would be marginal as checking gear down is part of the bread-and-butter procedures for all retractable gear aircraft. Keep in ...


35

Only in military applications nowadays, primarily helicopters as the system doesn't require the alignment process of the INS system, is not subject to GPS jamming, is very accurate when flying low (as opposed to high and fast over oceans), and most helicopters don't do the occasional barrel roll (the system is belly mounted to track the ground below). (Calm ...


34

The fly-by-wire is absolutely vital for control of the aircraft, and the three dominating factors here are safety, safety and safety. Weight is not one of them. The fly-by-wire system is triple or quad redundant: instead of removing a set of cables, the manufacturers are installing 3 more cable looms, just to make sure that the system always works. Wires ...


34

As a software engineer who works at a defence company that develops and sells mission critical (but not safety critical) systems, I can confirm that there's a pretty even split between development in Ada (95) for our legacy products and various flavours of C/C++ for our new products. Development in both is of course done to the appropriate standards. Python ...


33

The flight director is related to the autopilot system. It displays a guide on the artificial horizon, which shows the attitude of the airplane, but does nothing to control the plane. The guide represents a reference of an airplane attitude that will follow the parameters set for the autopilot. The pilot can manually fly the plane directly where the flight ...


32

Large commercial aircraft typically rely on either Angle of Attack (AoA) Vanes or Differential Pitot Tubes (Smart Probes (PDF)) to supply input to flight computers for the purpose of calculating AoA. AOA Vane When the computer(s) calculate an AoA nearing the critical angle, an impending stall is communicated to the pilots. There are visual indications, ...


31

I understand where you are at with this, I'm going to start off with a bit of math to show how it's not workable. Commercial airliners move quickly, even in a controlled glide one is going close to 3 miles (4-5 km) per minute. To give people on the ground enough useful warning to perhaps find some sort of cover you would need to give at least 20 seconds. ...


31

Non-holographic radar systems such as those used in fighter aircraft and active guided missiles only point in one direction at a time. Normally, when the radar is in search mode, a mechanism inside the radar makes the beam move from side to side (possibly up and down as well), so it has a wider field of view and can pinpoint the direction of any aircraft it ...


30

Commercial aircraft have fuel dump nozzles located under the wings for dumping fuel. Fuel is gravity jettisoned from the tanks located in the wings and the fuselage. Large commercial aircraft such as the 747 can dump upto 6000 lbs of fuel per minute with all fuel jettison pumps open. Interestingly, the fuel dump nozzles are in different places on ...


30

It has been tried before. Piper's PA-28R and PA-32R aircraft were equipped with an automatic landing gear extension system which would automatically extend the landing gear below 85kts regardless of the position of the selector switch in the cockpit. At higher airspeeds this system was overridden by a separate pneumatic system which deferred control to the ...


29

In most common passenger aircraft brakes are automatically applied when the gear is retracted. The wheels stop spinning before they enter the wheel well. This is particularly important because a spinning damaged tire may cause damage to hydraulic and fuel lines which are usually routed near the wheel bay. The nose wheels have no brakes, so they are ...


29

The short answer is that no safety-critical avionics systems that I'm aware of use Linux, and the highest criticality systems often don't use a commercial operating system at all. However, Linux is used in other safety-critical applicaitons like the Space X Falcon 9 and medical applications. A more detailed explanation is difficult to do without going into ...


28

As of currently, the answer to this question is in principle no for commercial aircraft, at least not remotely. There are two parts to this: From a system perspective: Aircraft systems could probably be 'hacked'- assuming you could for instance screw up the flight computer by changing the chips in the belly- but there is no way you could really pull this ...


28

No. It doesn't have an APU — it has two of them. They are located close to the main landing gears. From An-225 Mriya is the world’s largest aircraft (English version): Auxiliary power plant consisting of two TA-12 turbofans installed in the left and right chassis fairings provides independent power to all systems and starts the engines. I think "...


27

The RAT is automatically deployed on many aircraft, including the CRJ and A320 series, but it can be manually released as well. In between the loss of power and the RAT spins up you have the batteries to fall back to which are normally fully charged. The Airbus Manual has the following comment on the APU: In case of total loss of all main generators, the ...


27

Induction motors turn at a speed proportional to frequency, so a high frequency power supply allows more power to be obtained for the same motor volume and mass. Transformers and motors for 400 Hz are much smaller and lighter than at 50 or 60 Hz, which is an advantage in aircraft (and ships). Transformers can be made smaller because the magnetic core can be ...


26

The question was formulated in the context of a jet liner such as the Boeing 737-800 or the Airbus, I do not understand why there are persons responding to this question in the context of a smaller less complex aircraft. With that being said, I will like to expand the answer by DeltaLima. Boeing uses a device attached to the Brake Metering Valve Module ...


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