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Questions about various sensors used in aviation, both on aircraft and ground equipment.

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2answers
91 views

How is an out-of-trim condition (in relation to weight distribution) detected on the ground?

My question relates to Captain reports Out of trim and this answer. How is an "out-of-trim" condition like the one mentioned in the linked question detected on the ground? I.e "out-of-trim" in the ...
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1answer
140 views

Which company manufactures the air data system on the Boeing 787-9 'Dreamliner'

I'm asking specifically about the manufacturer and model of the Pitot probes/tubes that provide the pilots with current air speed readings. Pretty sure it's either UTC or Honeywell but can't find ...
1
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1answer
120 views

What are heat detection sensors and how can they cause a speed error?

From this news article on Saratov Airlines Flight 703: A report handed down by Russian investigators has blamed human error for the crash of Saratov flight 703, saying the pilots didn’t switch on ...
8
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1answer
291 views

What additional functionality is provided by the F-14 nose pitot, absent in early models?

Early model F-14A had no nose pitot: ... but they seem to have quickly acquired them sometime in the late 1970s. The Iranian F-14s have them, and it's quite hard to find a picture of an F-14 without ...
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1answer
103 views

What devices measure EPR & RPM on a turbofan engine?

What devices measure EPR & RPM on a turbofan engine?
6
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1answer
342 views

What sensors are required to fly RNAV 5 airways?

In the example shown above: Is an aircraft required to have all 3 sensors listed or just one of them to fly the L512 airway? What ICAO reference confirms the answer? Does 'critical DME' (bottom row) ...
1
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1answer
339 views

Does a Boeing 737 NG have Air Data Modules for the standby Pitot probe and static pressure port?

In other words, how does the ISFD calculate the air data and IR parameters? Or is the ISFD an ADM by itself?
13
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3answers
1k views

Do modern airliners have oxygen sensors in the cabin?

I know that airliners have pressure sensors to check the cabin pressure, and thus check if we can breathe (and get enough O2) inside it so we don't get hypoxia. But that got me thinking: Is there any ...
5
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1answer
702 views

How do tyre pressure sensors in aircraft work?

I am specifically interested in the sensors used on B777 and B787.
4
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3answers
720 views

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?
14
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1answer
2k views

What are these sensors on the Night Stalkers' Chinook MH-47G?

What are these sensors (or lights) on this heavy assault Chinook MH-47G of the US 160th Special Operations Aviation Regiment, "Night Stalkers"? Source, picture by Russell Hill This regiment was the ...
3
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3answers
780 views

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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0answers
144 views

What may cause a pitot tube and Honeywell pressure sensor calibration inconsistency?

It is possible that my issue is specific to my setup, but I thought I'd try here if someone has experienced a similar issue. I will try to explain this clearly as possible, but it may be slightly ...
2
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1answer
239 views

How can avionics detect tailwind? [duplicate]

We can see the effect of the tailwind on the plane's flight direction on the modern military fighter jet huds. I wonder about how can the avionic systems detect tailwind and which sensors using in the ...
3
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4answers
2k views

How are pitch angle and pitch rate measured in an airplane?

What equipment or method is used to obtain measurements of the pitch angle (θ) and pitch rate (q) during flight? Edit: I am asking about how the aircraft systems sense these quantities
5
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2answers
2k views

What is the difference between IMU (Inertial Measurement Unit) and AHRS (Attitude and Heading Reference System)?

According to online sources like wikipedia the difference belies on the addition of an on-board processing system (I assume it means a microcontroller) which outputs already processed data and not ...
4
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1answer
99 views

Is there a system of automated sharing of current (experienced) weather between aircraft in flight?

For example, if say - Aircraft 1 is flying a certain route, being followed by Aircraft 2 at an interval of say, 5 minutes (over the same position). Is there a system by which Aircraft 1 can transmit ...
2
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1answer
231 views

Is there a practical use of streaming data received from meteorological sensors installed on aircraft?

I am not the practitioner in the field of aviation, and my knowledge is mainly theoretical. Therefore I would be happy to get a feedback from practitioners on the following topic: I was reading about ...
6
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1answer
785 views

What is the purpose of proximity sensors on hydraulic systems?

One of the planes I worked on had ground spoiler response checked with proximity sensors. The reason mentioned for that was - "The ground spoiler is hydraulic only - hence its response will be checked ...
4
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2answers
692 views

What is this pod at the wing-tip of a U2?

In this image of a U2S, what it the very unaerodynamic looking pod at the wing-tip? It looks like it holds some sort of sensor package. However, it doesn't seem to appear on all U2s (at least not ...
15
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1answer
2k views

What is this device protruding from the rear of this 787?

While looking at the photos from this question I noticed a small protrusion from the side of the plane. You can see it in the photo: and in the diagram from l@aeroalias answer: In the diagram it ...
9
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4answers
3k views

What is the ultraviolet signature, if any, of aircraft and jet engines?

The Wikipedia article on the FIM-92 B variant of the Stinger Missile says: In this version, the infrared seeker head was replaced by a combined IR/UV seeker that utilized rosette scanning. This ...
3
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1answer
225 views

Can a laser Doppler anemometer be used to measure airspeed?

Could this be used in place of or in addition to a pitot-static system?
29
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2answers
3k 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:...
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2answers
3k views

How would the Airbus A320 PFD respond to failure of all pitot and AOA sensors?

In theory, if all 3 pitot tubes and all 3 AOA-sensors would fail simultaneously for a period of time, could the PFD still deliver correct roll angle and horizontal displays? How would the plane ...
4
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2answers
3k views

How does a pilot know if he has headwind, tailwind or crosswind?

While in cruise, without GPS how does a pilot know the wind direction? The airspeed sensors only register forward speed. Is it a matter of reaching waypoints sooner or later? And if flying on a ...
30
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2answers
3k views

What is the smiley face sensor at the stern of the F-4 Phantom?

The F-4 Phantom has an interesting collection of sensors at the extreme rear of the empennage. What are these sensors for? My daughter calls them them smiley sensors but I suspect that is not the ...
2
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1answer
365 views

Do fuselage rip/crack/damage sensors exist?

Are there sensors that can detect a rip, crack or damage in the fuselage skin by not using air pressure differential on aircraft?
16
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4answers
2k views

How does the Guardian counter-MANPADS system work?

I came across this picture of a FedEx McDonnell Douglas DC-10 equipped with an anti-missile defense system. (wikimedia.org) According to the picture description: FedEx became the first U.S. ...
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2answers
16k 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 ...