Questions tagged [avionics]
Avionics is applied electronics to aviation. Radars, radios, instruments, dashboards, they all belong to this category.
302
questions
51
votes
3answers
21k views
Why is Python used on aircraft although it may not be certifiable?
I recently had a discussion with people who were active in the aviation industry and told me that one of the main languages/tools they use is Python.
On the other hand I have always known that people ...
asked Oct 11 '17 at 20:40
LandonZeKepitelOfGreytBritn
7331 gold badge5 silver badges12 bronze badges
50
votes
3answers
10k views
How dissimilar are redundant flight control computers?
Facts
On Airbus aircraft there are computers to secure the flight envelope, or to move the control surfaces. FADECs totally control the engines. Computers take decisions in place of the pilots, or ...
49
votes
4answers
27k views
What programming languages are used for equipment onboard aircraft?
Generally speaking, What programming language is used in aviation for (ATC Radio, Radar, ILS, Auto-pilot and on-board avionics)?
Is there a standard enforced by ICAO?
Does every plane manufacturer ...
40
votes
12answers
31k views
Why don't all commercial aircraft transmit GPS data in real time?
It seems strange that trucks and taxis can be set up to transmit GPS data in real time but aircraft cannot. Wouldn't this be a useful function and feasible to implement?
34
votes
1answer
7k views
How does WiFi work on an aircraft?
I've noticed that when a WiFi system is set up on an aircraft, a small bulbous structure is added. What does it contain and how does this WiFi system work?
33
votes
3answers
2k views
Could the CVR and FDR record to the cloud?
Another enthusiast question. I watch a lot of the National Geographic Channel's "Air Crash Investigation", for better or worse, and it seems accident investigators make tremendous use of the Cockpit ...
33
votes
2answers
5k views
What are these boxes built into the tails of some fighters?
In looking at European-designed fighters of the 4th and 4.5th generation, I keep seeing a common design feature; a box-like structure built into the tail, often in the top half or third. Some examples:...
32
votes
2answers
7k views
What exactly did this mechanic sabotage on the American Airlines 737, and how dangerous was it?
An American Airlines mechanic sabotaged a 737 in Miami
An American Airlines mechanic accused of sabotaging a navigation system on a flight with 150 people aboard at Miami International Airport was ...
32
votes
3answers
32k views
Are fighter jets designed to be so inherently unstable that a human can't fly one unassisted?
I'm told that in order to be more maneuverable fighter jets are designed in a way that makes them impossible for a human to control without the help of a flight computer. Is this actually true? ...
32
votes
3answers
6k views
Are there common standards for aviation graphical user interfaces?
I'm searching for graphical user interface in aviation guidelines.
Yet I miss the correct terms and I don't really know where to start.
Let's take an example:
what's the meaning of the green ...
31
votes
2answers
54k views
How does an alpha (AoA) vane work?
The alpha vane (also called AoA vane) is an external probe used to measure the angle of attack. I have been trying to understand how exactly it works, but I can't find any clear explanation or ...
30
votes
3answers
7k views
Why are on-board computers allowed to change controls without notifying the pilots?
Recently we've had the 737-MAX debacle, where it increasingly appears that the MAX on-board MCAS system repeatedly would issue nose-down events, leading to the Lion Air crash, and possibly another
...
29
votes
3answers
4k views
What kind of delay does the A320's fly-by-wire system add?
More precisely, I am wondering if there is any kind of data on how long it takes between moving the sidestick and observing a reaction on the ailerons or elevator. I know that the physical control ...
28
votes
6answers
16k views
Is it possible for a modern commercial airliner to stop being tracked without substantial mechanical failure?
I was speaking to someone about the MH370 incident, and they suggested that a hijacker could turn off the device that sends the plane's current position, resulting in the appearance of a catastrophic ...
28
votes
3answers
3k views
What's the UX in modern airliner avionics for diversion choices, and does it integrate to autopilot?
This question mentions a flight that had to divert, in that case to Iqaluit (YFB).
I was wondering: in modern large airliners, what is the user interface like when diverting? How is the case of "what ...
23
votes
5answers
8k views
Do safety-critical avionics systems run Linux?
I have heard diverse things about this. Some people claim that running Linux on safety-critical avionics systems is a very bad idea. On the other hand some people (who are rather unfamiliar with ...
23
votes
3answers
2k views
What is ADS-B and who needs it?
I read that ADS-B is required by the year 2020. What does this mean? What is ADS-B used for, and who needs it?
23
votes
3answers
2k views
Why are FDRs and CVRs still two separate physical devices?
Given the histories of flight data recorders and cockpit voice recorders, I somewhat understand their origins as two separate physical devices. Given their separate tracks of development, regulatory ...
23
votes
1answer
5k views
Do aircraft manufacturers produce their own black boxes?
Do the manufacturers who build airplanes use their own "black boxes" in the planes, or are there companies whose sole purpose is to develop black boxes?
For example, in 2010 in the Airblue Flight 202 ...
22
votes
5answers
4k views
Could a Personal Locator Beacon or EPIRB carried by a passenger aid in locating a downed airliner?
There've been a lot of questions lately about tracking aircraft, and after a conversation with a friend of a friend I started wondering:
Could a PLB or EPIRB carried by a passenger or crew member aid ...
20
votes
12answers
7k views
Why are critical flight computers redundant?
At least in airliners, the truly critical computers are redundant. Typically three identical copies of the autopilot computers run in parallel and compare results; if one computer disagrees with the ...
20
votes
4answers
11k views
Like transponders, can flight recorders be turned off?
I never knew much about airplanes before the tragic incident of Malaysia 370. I have been spending a lot of time on Twitter reading various articles and investigations; in one of the articles I read, ...
20
votes
3answers
5k views
Do planes have odometers?
I'm curious to know if planes have distance counters similar to the ones in cars indicating how many kilometres/miles the plane has flown since being put in service.
19
votes
1answer
14k views
What exactly distinguishes a beacon light from a strobe light?
Different sources seem to have different opinions:
Wikipedia: Aircraft warning lights:
These lights include landing lights, red or white flashing beacons, wingtip strobes, and wingtip navigation ...
18
votes
2answers
27k views
How does TACAN work?
How does the Tactical Air Navigation (TACAN) system work? How is it different from the VHF Omnidirectional Range (VOR) system? Please explain in the simplest possible way.
17
votes
2answers
3k views
How does an aircraft derive winds aloft on its own?
The G1000 has a feature where it can put up a winds aloft arrow/speed in the PFD. I've been sort of wondering how exactly this is determined. My guess is that the aircraft (or the G1000) knows your ...
16
votes
6answers
6k views
Is it possible to accurately measure airspeed without pitot tube?
This is a follow-up to my previous question:
How does this IMU work and how to convert its output into meaningful information?
for which many people asserted that I need a pitot tube and a static ...
16
votes
1answer
2k views
Why is it hard to see G1000 with sunglasses?
I got checked out in the G1000 172 at my flight school just so I could schedule to fly when the two steam gauge 172s were booked. I'm very impressed by the G1000, but I can't wear sunglasses when I ...
16
votes
1answer
3k views
Why do helicopters and airplanes use different headset plugs?
If the headsets and microphones for general aviation have the same impedance for helicopters and airplanes, then why do they have different connectors on them?
Is it simply to make more money from ...
16
votes
2answers
5k views
When should a transponder be used?
When should a transponder be turned turn on?
On the ground?
Always in flight?
Only when required: during radar service (flight following), above 10,000ft MSL, inside the Mode C Veil, or on IFR flight?...
15
votes
3answers
2k views
What does “synoptic” mean in avionics?
I came across a mention of a display of "graphical aircraft system synoptics" on this page. I think in context that it means "status display" or "summary page"- the page that shows flap position, ...
15
votes
3answers
4k views
Why shouldn't you use HF radio while refueling?
FCOM limitations for many aircraft state:
DO NOT USE HF RADIO WHILE REFUELING
Why is this? I have heard from people that it's because most of the big airliners have a 'notch' antenna for HF; it's ...
15
votes
2answers
5k views
Which CPUs and programming languages are used in new airliner flight control systems?
Are the new systems of today built with the same CPUs and programming languages and development software as those of 20 or more years ago?
By new I mean that these systems are currently being ...
14
votes
2answers
12k views
How precise are altimeters?
How precise and how accurate are typical altimeters these days? That is, if two planes are flying (side-by-side, very near each other), and both altimeters show the same Flight Level, what is the ...
14
votes
2answers
15k views
What is the difference between CAN and ARINC?
I want to know the difference between CAN and ARINC, I'm confused about their usage.
For example, the communication between the cockpit and the controllers is done using ARINC protocols. And the data ...
14
votes
1answer
915 views
Did the contemporaries of the F-14 also have automatic swing wings?
The F-14's Central Air Data Computer was a innovative design, using microprocessors for its implementation. This computer was used to control the swing wings of the F-14.
How did the contemporary ...
14
votes
2answers
984 views
How is an on ground lightning strike test conducted?
Whenever a design company is obtaining an STC for an aircraft (Supplemental Design Certificate) for an electrical installation, one of the required tests to obtain the STC is a lightning strike test. ...
13
votes
1answer
898 views
What coming changes might render current IFR equipment worthless in the foreseeable future?
I'm shopping for my first aircraft. I have found a very well cared for 172 that is VFR. I also found an IFR-certified 172 that is higher time and cosmetically is showing its age. I inquired about ...
13
votes
3answers
1k views
How are avionics updates delivered?
I'm idly curious to know what type of physical storage medium (e.g. is it a "mini-CD", USB key, a little hard drive, maybe a tape) is used for delivering avionics updates, for an as-recent-as-possible ...
12
votes
1answer
6k views
How is varying modulation depth achieved by localizer ground transmitters?
An approaching aircraft's navigation receiver uses the difference in depth of modulation between the 90Hz and 150Hz signals which are amplitude modulated onto an RF carrier (on a channel between ...
12
votes
3answers
3k views
What's the difference between orientation and position?
In INS (Inertial navigation system) sensors, is there a distinction between the following?
Orientation (heading, pitch and roll)
Position (latitude, longitude and altitude)
Is the orientation ...
12
votes
2answers
2k views
Are there any accident reports that mention hacked/compromised avionics as a factor?
Does anyone know of any documented examples of airline accidents caused by hacked or otherwise deliberately compromised avionics?
12
votes
3answers
4k views
What is the history of glass cockpits?
All glass cockpits seem to have the same basic setup for the primary instruments. Altitude tape on the right, air speed tape on the left, turn coordinator on top and an artificial horizon in the ...
12
votes
2answers
1k views
What do the gyroscopes used in commercial aircraft actually look like?
I pretty much grew up watching Air Crash Investigation and Seconds From Disaster and every other episode had a mention of the aircraft’s gyroscopes, but I always wondered how did FAA rated industrial ...
12
votes
2answers
2k views
Do military jets' radar jammers block their own radar? And, if not, why not?
Will a noise jammer block the fighter's own radar? If I have understood it, a noise jammer, e.g., a barrage jammer, will emit a noise signal across a wide frequency band. Won't this make it hard to ...
12
votes
1answer
448 views
What is the Space Shuttle's command law?
The Space Shuttle was fly-by-wire. In today's fly-by-wire systems, the command law commands either the load factor and the roll rate (e.g., A320's normal law), or the surface control deflection (e.g., ...
12
votes
1answer
2k views
How do I tell a Garmin 430 not to exit a hold?
Let's say that we're directly west of CATLI and have been cleared direct CATLI for the RNAV approach. We load the approach into ...
12
votes
1answer
3k views
What are the “channels” on the A320 Rudder Travel Limit Unit?
The KNKT's final report on last year's Air Indonesia QZ-8501 crash repeatedly mentions that the faulty solder joint on the Flight Augmentation Computer (FAC) caused an open circuit on "both ...
11
votes
3answers
11k views
Why didn't the A330neo and A320neo share the cockpit of the A350?
Recently Airbus presented its lastest projects A330neo and A320neo.
I'm sincerely surprised about the cockpit, in that it is essentially the same of the original A330, while I was expecting that ...
11
votes
3answers
1k views
Is VOR identification automated in modern avionics?
Is the VOR identification via audible Morse code automated in modern autopilots / avionics?
Or does a pilot in an A380 still sits in there, listens and compares the .-. .. -.. to her charts?
