Questions tagged [aircraft-systems]
The essential systems found on most aircraft, including power plants, fuel systems, electrical systems, and flight instruments.
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What is the fluid released from the tail of this clipped Turkish airliner?
A Turkish A321 airliner was hit by an Asiana A330 on 13 May 2018 at Istanbul Airport. It seems a large amount of fluid was released from the damaged section. What is the fluid? There is no APU up ...
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How to calculations deviation on a magnetic compass and effect of it?
I am told to do self study and mainly for the part of the formula reading and i did some research and don't understand a single thing that i read online http://opac.vimaru.edu.vn/edata/EBook/Magnetic%...
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What is the risk of leaving the MAN START PB 'ON' on the A320?
During a manual start on a A320, the ENG MAN START P/B opens the start valve which then runs the starter motor. During the MAN START process, at some point, the start valve closes automatically. What ...
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How does the Boeing 787's Cabin Air Compressor work？ [closed]
How does it work in normal, overheat and over-pressure conditions? What is the function of the variable diffuser actuator?
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White light illuminating the engine coming on at intervals in flight; Curious what's the protocol?
I was recently flying Air China from Beijing to Bombay & happened to seat on the Window seat close to the wings.
I could see the engines and there was a light that could illuminate the engines. ...
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Does the flight crew in big airliners hear the cabin crew PAs?
In big airliners, does the flight crew hear the PAs the cabin crew is doing to the passengers, e.g. on their headsets? If not, how do they make sure they’re not talking simultaneously to the ...
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What minimum radio communication equipment is required in a homebuilt aircraft in India?
Let's say I am building a single seat aircraft for flying in one's own country(India). What should be minimum set (Not only from compliance prospective but to have core set of communication for ...
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Does the parking brake provide additional deceleration in an abnormal situation?
During a rejected takeoff at a speed > V1, you obviously try to stop with all available means since a runway overrun is a very undesirable result. In this case, could using the parking brake in ...
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Does the Flight Data Recorder store the data locally or send it to an offsite backup while in flight? [duplicate]
I was wondering, what a black box actually does ? Does it store the in flight data, in case an accident should occur or it's sending it to an offsite backup while in flight ? And if it stores the data,...
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Can I use parachute fabric to cover an aircraft fuselage and wings?
...
Are there disadvantages to using parachute fabric to cover an experimental aircraft? So far I observed the following:
I believe I put this fabric in an open place for a year
I found no cracks ...
user30137
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Why are parking brakes not used for parking jetliners?
From the question 'Do I Set the Parking Brake On the Ramp?' it is concluded that you do not set the parking brake when parking the aircraft.
The question concerns small aircraft which can be parked ...
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Why disable stall warning based only on low airspeed, rather than multiple criteria?
One of the factors that potentially contributed to the Air France 447 crash is that the stall warning was disabled when the airspeed fell below 60 knots.
I understand why this is -- you don't want to ...
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What solutions are there against deep stalls?
What solutions are there against deep stalls?
According to SKYbrary:
Aircraft with a T-tail design are often configured with a Stick Pusher system to help prevent the mainplane angle of attack ...
user14897
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Do any newer production aircraft use venturis as a backup vacuum source?
I began my flight training in a Cessna 120 with 2 venturis as the source of vacuum for my DG and TC. They worked well in flight.
Are there any aircraft with deployed/deployable venturis out there? ...
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What is the difference between an APU and an ATS?
Is there a big difference between what an Auxiliary Power Unit (APU) and an Air Turbine Starter (ATS) system actually does?
My understanding is that an APU provides power for the electrical systems ...
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Are the details of flight control laws the same for every fly-by-wire Airbus aircraft or are they only the same within the specific family?
I was wondering if someone learns the details of every single flight control law for the A320 family, does that knowledge still apply to all the other Airbus aircrafts? If not, what are the ...
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(B737s) Why is the automatic activation range of the AUTO mode in flight limited to "between idle and 5%"?
This is the explanation on the Engine Start Switch in the 737 series FCOM. What might be the reason why the automatic activation range of the AUTO (or OFF) mode in flight limited to "between idle and ...
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What dictates the A320's 'emergency ram air inlet' operation?
Why does the emergency ram air inlet flap open when delta p is greater than or equal to 1 psi on the A320?
Below is the extract I was reading from the FCOM. Why has the figure of 1 psi been set for ...
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What design features or systems help to prevent a hard nose landing?
Pilots perform perfect manual landings almost all the time with the nose wheel touching down softly and elegantly. When landing an aircraft of any size really more so for the jumbos and super jumbos, ...
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Why doesn't the A320 pack flow indicate HI as it should?
When on ground with APU bleed on and both engines off I have noticed a number of times that the pack flow isn't at the HIGH setting why?
As per the FCOM it states that when APU bleed is on the PACK ...
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What happens if an aircraft's hydraulic system starts leaking during a flight?
What will happen if hydraulic fluid starts leaking during a flight? What will happen to the overall performance of the flight, and how will the pilot compensate for the loss of the system?
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What is the function of ECS in airplane? [closed]
What is the function of ECS in airplane?
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What is the difference between variable and transient bleed valves?
What is the difference between variable bleed valves (VBVs) and transient bleed valves (TBVs)? What is their range of operations? Can they be used at all airspeeds?
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Why does the Boeing 787 use Cabin Air Compressors (CACs)?
What are the advantages of this new air conditioning system compared with the traditional engine bleed systems? More engine output power, or easier adaption to future aircraft design?
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Why is it called "STBY RUD" on a Boeing 737?
(Source: b737.org.uk)
Anyone knows why "STBY RUD" is named "STBY RUD" when the selection of the switch position activates the standby hydraulic system as well as the standby rudder system (by opening ...
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When does a 'flaps/slats misconfiguration' warning sound during takeoff roll?
If a flight crew begins their takeoff roll and don't have slats and flaps configured properly, when does the system know when to sound the alarm? If it actually sounds during the roll itself, that ...
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How are the services kept running on a plane without an APU? [duplicate]
I have seen several aircraft that do not have an operative APU, so how are lights, air, and other systems kept running?
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What is this fuselage-side aerial used for?
(instagram.com)
I have seen this picture, and this feature on the port fuselage called my attention. Does anybody know the purpose of this?
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Is this opinion on personal computer flight simulators too strict or is it actually true?
A couple of days ago I had a discussion with a commercial pilot and his opinion on personal computer flight simulators were a bit surprising to me.
He said that flight simulators, even with ...
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Why do some aircraft have to have the landing gear pinned prior to towing?
The Phenom 300 require all three gear to be pinned before towing. I assume there are other aircraft with the same restrictions.
The nose gear is understandable, due to the link being pinned out of ...
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What is this button (pressed during approach) on the Airbus A320?
I was watching a YouTube video of a cobalt air a320 landing and I seen as he was about 2000 ft AGL he pressed a button on his right hand side just beside the Navigation display. The button illuminated ...
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Is Doppler navigation still in use for civilian aircraft?
Is it possible to find an airliner nowadays with Doppler radar used for navigation purposes?
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How does hydraulic actuator servo valve feedback work?
The book Aircraft Systems uses the following diagram for a mechanically controlled hydraulic linear actuator (for moving a control surface e.g. an aileron):
The following explanation is given about ...
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What is the purpose of anti-skid surge accumulator in a 777-300?
What is the purpose of the anti-skid surge accumulator in a Boeing 777-300?
What would happen if it were not present and why is it only meant for the left landing gear wheel assembly?
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What is the transient bleed valve in a gas turbine engine?
What is a transient bleed valve and what's its purpose ? Also, can you explain the purpose of bleed valves in general?
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What is the purpose of the fin at the Boeing 787 APU exhaust?
The fin is located under the Boeing 787 APU exhaust as shown in the picture below. Does anybody know the application of this thing or it is used for 'guiding' the APU exhaust? Thanks.
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How does an Airbus aircraft connect to the Internet? [duplicate]
I would like to understand better where (physically in the aircraft) and how the Internet connection is received on an Airbus aircraft, in particular in an Airbus A380, and then how this system is ...
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How long does the gear extension/retraction takes on the ATR-42?
Which is typical time of landing gear extension in normal conditions ? I would like to know it especially for the ATR-42 but any other typical value is welcome !
Furthermore can you provide any link ...
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Why isn't cabin air quality in airliners directly monitored with sensors?
Airliner air conditioning systems refresh the cabin air volume every couple of minutes. A portion of it is filtered and re-circulated into the cabin, however AFAIK there are no direct cabin air ...
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How are electronic systems locked and connected in the electronic bay?
On aircraft the electronics bay contains multiple systems, e.g. for the A320:
A320, photo by B-2230, source: JetPhotos
How is the electronic equipment locked (it seems there are two mobile screws) ...
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Is wheel well overheat detection (not brake temperature sensor) necessary for commercial jet aircraft?
Some aircraft do have this detection system (many Boeing aircraft), some do not. Why? What's the main purpose of the wheel well temperature detection system, even though there are brake temperature ...
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Why do flight control cables not slacken during the cold temperatures at cruise?
Image source
Flight controls in airliners have long cable lengths in between the cockpit controls and the control surfaces. For instance in the picture above: the pilot operates the yoke, which ...
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How does the nitrogen generation system in a Boeing 777 work?
How does the nitrogen generation system in a B777 work and how does it differ from that used in a B787? Any diagrams will be appreciated.
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What kind of OS or programming language does the aviation use? [duplicate]
Windows XP because its the most stable system ever ?
C++ because its the most verstatile thing ever ?
Also I am not limiting this question to avionics but to
Garmin GPS/Glass cockpit
B737 Flight ...
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What is NH overspeed test and how it is preformed on DHC Q400 aircraft?
In the Aeroplane Operating Manual of DHC Q400 aircraft it is written that, at the time of normal engine shutdown, the engine system tests the NH overspeed circuitry by using it to shutdown the engine. ...
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What's the reason for "pre-pressurization" of the cabin prior to liftoff? [duplicate]
I'm reading a Citation M2's Pilot Training Manual, and it says:
...When the throttles are advanced for takeoff, the bleed air turns on
(if not already on for heating), and the pressurization ...
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How does SLATS/FLAPS retraction damage the RTLU mechanical stop if we retract them after the ADIRS are set off?
From the A320 After landing FCOM NORMAL PROCEDURES:
To avoid damage on the RTLU (Rudder Travel Limit Unit) mechanical
stop, the SLATS/FLAPS should be retracted before all ADIRS are set to
OFF ...
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What types of fuel quantity sensors are used in an aircraft? How do they work?
Can you explain the different types of fuel quantity sensors used in most recent aircraft?
Are ultrasonic tank sensors used these days? How does an ultrasonic sensor work?
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What's field excitation in an electrical system?
"A field relay in the GCU (generator control unit) allows or prevents field excitation within the generator. When open, the field relay deprives the associated power relay of its ground, which causes ...
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Have there been fully pneumatic aircraft?
Have there been any passenger aircraft that used pneumatics for all of their on board systems that required force actuation, such as:
landing gear;
wheel brakes;
nose wheel steering;
propeller ...
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