Questions tagged [redundancy]
For questions about the use of multiple similar components to keep a single failure from being catastrophic.
18
questions
0
votes
2
answers
169
views
How to identify the faulty GPS-INS in dual redundant installation?
If we have two GPS-INS sensors on an aircraft, how can we decide which one is giving the correct measurement? I know that for sensors, we can vote, but what if we have two sensors? Please give me a ...
8
votes
4
answers
2k
views
Are there wool threads for displaying angle of attack?
Like there is a wool thread on a glider's canopy for showing relative wind on yaw axis. Are there or have there been a wool thread as a long term mean of showing angle of attack?
For instance placed ...
5
votes
2
answers
901
views
Do aircraft have backup systems to trim when they don't have trim wheels?
What happens if the motor that trims the elevator of an airplane fails and there are no trim wheels in the cockpit (like in the Boeing 747). Is there a backup system or hidden trim wheels?
2
votes
1
answer
179
views
What is the Correct Procedure to Test Portable Backup Airband Radio (US)?
I recently obtained a portable air band radio for use as a backup radio in flight. As this is a backup, it isn't much use without being tested. I'm trying to determine the proper way to test the ...
6
votes
2
answers
466
views
Have attitude indicators ever had triple failure in a commercial aircraft?
I'm wondering about couple of well known crashes (mainly AF447 and AirAsia 8501) and thinking: is there any case where triple redundant attitude sensor failure has ever occurred? In those accidents it ...
0
votes
0
answers
194
views
How is the control surface configuration of predator/reaper for redundancy system?
In commercial aircraft like Airbus or Boeing, there are several control surfaces that work in the same function such as for roll control capability, the control surfaces are aileron and spoiler. Also ...
1
vote
1
answer
341
views
How many Angle of Attack sensor vanes should a commercial passenger airliner have? [closed]
The ill fated MAX of recent news had 2 angle of attack vanes, with the MCAS computer picking the worst one.
It seems a "software patch" may not be the only improvement option available. Sensible ...
26
votes
5
answers
10k
views
What is the rationale for single engine military aircraft?
In aeronautics, redundancy is of primary concern. Having at least two engines is common for civilian aircraft. I expect the military to have at least the same level of redundancy. Moreover military ...
0
votes
1
answer
236
views
How reliable is keeping flight maps on an iPad in the cockpit? [duplicate]
Are flight maps no longer kept on a shelf in the cockpit as a back up in case the iPads malfunction? One story that I managed to research highlighted that this was under debate to rely only on a ...
1
vote
4
answers
349
views
Why don't nonrigid airships have multiple gas cells?
Nonrigid airships (blimps) differ from rigids and most semirigids in having the entire envelope form a single large gas chamber, rather than dividing the lifting gas among several redundant gas cells. ...
2
votes
1
answer
302
views
What kind of flight-control redundancy does the Tu-204 have?
The Russian Tupolev Tu-204 and variants are reported to be digital fly-by-wire. Are they quadruplex redundant? Do they have manual or analog back-up systems?
18
votes
4
answers
4k
views
Why is not every airplane equipped with 3 angle-of-attack sensors?
For critical systems, redundancy is built into the system. It is common knowledge among designers/architects to have three different inputs so in case one is faulty, input from the remaining two can ...
2
votes
2
answers
582
views
Why don't aircraft carriers have multiple sets of arresting wires?
On this answer to this question regarding the merits of angled flightdecks on aircraft carriers, @JanHudec makes this interesting observation:
You don't really have "two flight decks". The ...
0
votes
1
answer
331
views
Why does the DHC-6 have only one set of elevator cables?
Air Moorea Flight 1121 crashed because its up-elevator cable broke, allowing the elevator to blow to its faired position and thus be unavailable to counteract the pitch-down moment caused by the flaps ...
3
votes
3
answers
387
views
Can horizontal stabilizer trim be worked independently (each side)?
I notice most jetliners have a big trim wheel on each side of the center console. This wheel is black with white stripes, and notably turns on its own via the autopilot.
Two large trim wheels: And ...
6
votes
1
answer
11k
views
What is the difference between redundancy and fault tolerance?
What is the difference between redundancy and fault tolerance in the context of aviation ?
54
votes
4
answers
13k
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 ...
13
votes
5
answers
3k
views
What alternative methods are there for controlling a plane when flight control surfaces have failed?
I saw a TV show once about Japan Airlines flight 123, in which the aft pressure bulkhead ruptured, disabling hydraulics and ripping off the vertical stabiliser. So the flight crashed after some time ...