Questions tagged [flight-instruments]

Flight instruments provide the pilot with information about the flight situation of that aircraft, such as altitude, speed and direction; and are of particular use in conditions of poor visibility, such as in clouds, when such information is not available from visual reference outside the aircraft.

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21
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4answers
5k views

What is this INOP instrument and when is it safe to fly with INOP instruments?

I flew ZRH->LHR on BA0711 today on G-EUOG. I noticed through the cabin door one of the instruments had a yellow INOP sticker across it (see photo). Which instrument was it? I am presuming the ...
5
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1answer
612 views

Why would a Mode-C transponder report a different altitude than an altimeter/GPS?

This is related to a small single-engined plane. On a recent flight, the controller kept telling me that I was 300 ft higher than it appeared on my altimeter and GPS (which were in sync). This was ...
7
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2answers
525 views

What instruments were “standard” in WWI aircraft?

What instruments made up a typical panel of a WWI airplane? Did any country regulate the required cockpit instruments prior to the United States "Air Commerce Act" of 1926?
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2answers
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Why are cockpit instruments white on black dials?

Which is easier to read: white on a black dial or black on a white dial? It would seem most aviation instruments are white on black.
7
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5answers
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How is a confusion possible between Western and Russian Attitude Indicators?

Yesterday I watched a documentary on Crossair Flight 498 accident. One of the factors that might have contributed to the accident was the confusion of the pilot on interpreting the attitude indicator; ...
3
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2answers
231 views

How does the mechanical linkage of the airspeed indicator convert dynamic pressure to KIAS?

I understand the underlying principle of an airspeed indicator, ie. that it uses the Pitot-static system to measure the dynamic pressure as the difference between total pressure and static pressure. ...
9
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2answers
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What other circumstances may cause the autopilot to trip out?

I recently watched Air Crash Investigation, Air France Flight 447. The autopilot handed back control to the flight deck after the pitot tubes temporarily froze. The autopilot knew it was getting ...
3
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1answer
327 views

How is the drift corrected in INS-driven attitude/heading indicators?

(wikimedia.org) EFIS instruments during a test flight. How is the drift (accumulated error) nullified in INS-driven attitude/heading indicators? The related post 'How are attitude indicators kept ...
10
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1answer
615 views

When was the pitot-based ASI first used on aircraft?

The pitot was first invented well before aircraft, yet early aircraft lacked an airspeed indicator (ASI). What aircraft first had a pitot-based ASI, and when?
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1answer
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Why is Landing Altitude displayed in amber on B777?

When I set the landing altitude manually, an amber LDG ALT and Landing Altitude EICAS message is displayed. There are no failures nor has the landing altitude been set incorrectly. Why do I still ...
4
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0answers
219 views

What aircraft manufacturer uses an HSI with DME, VOR, and G/S in one Instrument?

Which aircraft manufacturer uses a horizontal situation indicator (HSI) with DME, Glide Slope, VOR, and ADF in one Instrument?
7
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2answers
1k views

What is that missing instrument on a Beechcraft 1900C?

(Full image) Beechcraft 1900C. I cannot find the name of the missing instrument even in the manuals.
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3answers
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How (and when) to use the BFO button on an ADF?

BFO (Beat Frequency Oscillator) is a function of the ADF, I know that it has something to do with different types of NDB, but I do not know which type. And how and when do I use it? I heard that ...
24
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1answer
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How does the head-up display on a spitfire work?

It turns out that the Spitfire from World War 2 had a head up display. Does anybody know how it worked exactly? All I could find was this picture, but no explanation: Source The source does not ...
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3answers
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How much computing power is needed to keep commercial and military planes flying?

I've always wondered, what sort of computing power is needed to keep modern commercial and military planes in the air? There are many systems of a modern commercial plane (e.g an Airbus A350), that ...
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1answer
806 views

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 ...
3
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1answer
232 views

What instruments are used to indicate aircraft attitude in acrobatic airplanes?

As aerobatic airplanes don’t use gyroscopic instruments such as attitude indicators, what instruments are used to indicate the aircraft’s attitude in flight?
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3answers
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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 ...
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2answers
264 views

Why do Western aircraft manufacturers use FPS system while Russian aircraft manufacturers use MKS system for flight instruments?

Why is there a variation in aircraft flight instruments of aircraft from Western & Russian origin? Foot–pound–second system (FPS) Meter-kilogram-second (MKS)
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1answer
285 views

Why do ATC displays use flight data sent by the aircraft they are tracking?

Why does ATC use data coming from an aircraft itself instead of using the readings from the airport radar? Also could Aeroperú 603 have been saved if the pilots had ignored the pitot static altitude ...
3
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2answers
777 views

What is the difference between a “compass swing” and “check swing” procedure?

What is the difference between a "compass swing" and a "check swing" procedure?
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3answers
5k views

What was the first flight instrument ever used in an airplane?

It's not magnetic compass, turn coordinator, stopwatch, wind meter, VVI, and airspeed indicator. I want to know what is the first flight instrument.
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1answer
869 views

What are the differences between ADS + INS and ADIRS / ADIRU?

What is the main difference and advantage in the Air Data System, between the former architecture (ADS + INS) and the newer one (ADIRS/ADIRU)?
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3answers
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What is Engine Pressure Ratio?

I kind of know what it is but I don't fully understand it. Wikipedia says, the engine pressure ratio (EPR) is the total pressure ratio across a jet engine, measured as the ratio of the total ...
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2answers
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In the ARINC specification, why is baro altitude (label 204) measured in Knots?

I am currently designing a system that reads the baro altitude (on label 204) from an LRU. Ultimately in my software I would like to display the baro altitude reading in real-time using a graphical ...
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1answer
617 views

How does an engine driven vacuum pump used in gyroscopic instrument work?

In general aviation light airplanes (C152,C172,PA28..) how does the engine driven vacuum pump work?How is it made? and if the filter of one of the gyro instrument is clogged would the vacuum ...
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2answers
509 views

Is there any instrument similar to a compass but which I can electrically drive?

I would like to build a home weather station with analog instruments showing for example temperature, wind speed and wind direction. I would like to use a salvaged flight instrument to show the wind ...
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2answers
251 views

What is the correlation between RNP level and the CDI indication?

I got a question regarding the connection between RNP (required navigational performance) accuracy and cdi sensitivity of the HSI. According to the instrument flying handbook the standard for RNP on ...
11
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2answers
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What navigational aid(s) would WWII bomber pilots have used while flying in instrument conditions?

In my furthering attempt to understand the accident mentioned in this post, I've become interested in how WWII Bombers would have flown on instruments. In the accident report, the pilots states: ...
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1answer
131 views

Would fuel quantity indications be affected by extended flight at nonzero bank angles?

If flying with a 20kt crosswind requiring yaw input as well as roll input to maintain course, would the fuel indicators show different loads depending on the roll angle of the aircraft (in this case, ...
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2answers
286 views

Measuring speed and altitude from personal phone midflight [duplicate]

Given that there is no need now for one to swith off their cellphone midflight, inflight wifi is now a norm and common, Is it possible for me to measure the velocity and altitude of an aircraft using ...
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1answer
214 views

Are GPS airspeed meter and altimeter going to replace traditional measurements?

When are GPS Airspeed meters and Altimeters going to be introduced if they not already in use? Are they more accurate than systems in use now and? How much would it cost to install them to older ...
4
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1answer
705 views

Are there benefits in training instrument students how to fly a DME arc?

With more instrument approach procedures being designed for RNAV/GPS equipped aircraft, and considering the high level of radar coverage currently available, is there a need to spend much valuable ...
18
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1answer
3k views

What do the yellow lashes/wings on the B737 PFD indicate?

When I was looking at a YouTube clip of a B737 doing a landing, I couldn't help but notice something on the PFD: What do these yellow lashes/wings indicate on the artificial horizon? Image Source (...
6
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1answer
616 views

How do instructors simulate instrument failure in basic training aircraft with glass cockpits?

While working towards my private pilot's license in the United States in 2004-2005 (in a steam gauge only airplane), I very much remember my instructor covering one or more instruments to simulate ...
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3answers
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What prevents a Machmeter from being the standard airspeed indicator?

Airspeed is more accurate when displayed by a Machmeter than when displayed by an airspeed indicator. It isn't affected by ambient temperature / density changes. It is still affected by position error,...
9
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2answers
2k views

How does an Airbus pilot decide whether to use HDG-V/S or TRK/FPA guidance?

The Flight Control Unit of modern Airbus aircraft has a pushbutton for selection of either heading / vertical speed (HDG-V/S), or track / flight path angle (TRK-FPA) guidance for the Autopilot and ...
12
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1answer
400 views

How should this Bendix course deviation indicator from the '50s be read?

This is a Swissair photo from a DC-7C panel. Source I have seen photos on airliners.net of these in DC-6s, VC-118 and Constellations. It appears that other companies besides Bendix made these ...
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1answer
2k views

Statute miles to runway visual range [duplicate]

Is there a formula to converting statute miles to runway visual range? If so, what would it be? I'm seeing how 1 mile is equal to 5000 feet, but I am so confused because 1/2 of a mile is equal to 2,...
6
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2answers
2k views

What is the difference between a pitot tube and a pitot-static tube?

What is the difference between a Pitot tube and a Pitot-static tube? If an aircraft fitted with Pitot tube and static holes on the fuselage, is it necessary to consider the static pressure ...
28
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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 ...
5
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1answer
2k views

What are the pros and cons of vacuum and pressure gyros?

Inspired by this question, I would like to know what the pro's and con's of the mostly used vacuum-gyro and the less used high-pressure-gyro is. Side-question: Are there any other ways to make the ...
15
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2answers
998 views

What is this nose cowl mounted display?

(YouTube) A crop duster's nose mounted display. It looks like a poor man's HUD to keep the display and the outside view at roughly the same focus distance, but what is its function?
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1answer
416 views

On an inverted aircraft, is the ILS glide slope sensing reversed?

If I'm halfway through a barrel roll on final descent, on an ILS, will I get reverse sensing on my glide slope indicator?
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1answer
91 views

Why $\frac{\Delta p}{\overline q}$ is depending by weight, flap deflection and other parameters? Which are other parameters?

As you can see in this link (Roskam, Airplane Aerodynamics and Performance, Chapter 2.5.3 Airspeed corrections) ... ... in the first and second line of page 30 Roskam tells that, in hypothesis of ...
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1answer
550 views

What caused the loss of “everything” on Swiftair Flight QY-2939?

I found this from a youtube video, and more info from this avherald article. One of the pilots declares an emergency because right after takeoff they lost "everything", as in all instruments. ATC ...
4
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1answer
641 views

At what altitude do vacuum powered gyros become ineffective?

Obviously, in space a vacuum powered gyro would not work because there is no air to move, but, how high do you have to go before they are unable to spin fast enough to work properly? would a vacuum ...
3
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1answer
191 views

What techniques, tools, or instruments are used while performing zero-g parabolic dives? [duplicate]

There are companies that sell "zero g" rides, where the aircraft is configured specifically to take people and possibly experiments through a parabolic dive to experience a short period of micro-...
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2answers
4k views

How can pilots lacking instruments interpret vectors given by ATC?

This video is about European Air Transport flight 2939, a Boeing 737, which "lost all the instruments of the aircraft" shortly after takeoff. BCS2939: We are flying heading now, and we don't have ...
5
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2answers
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How does altimeter reading vary when departing from ISA conditions?

I am a soon-to-be student-pilot and am struggling with a basic concept that is altitude. After watching multitude of online videos, I feel that most of the people do not have good teaching skills. ...