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24

These are antennae for the IFF (Identification Friend or Foe) system. IFF is a system to help distinguish friendly aircraft from unfriendly ones. This particular antenna arrangement is used on only a couple of F-16 models. The first was the F-16 Air Defense Fighter (ADF) version. This model was converted from the F-16 Block 15 for use as a fighter ...


23

There are several reasons to have the pressure sensors in the front section of the fuselage. The further aft the more turbulent the airflow is and the thicker the boundary layer caused by the fuselage. This would cause strong fluctuations of the measured pressure and the reading could be inaccurate. Far forward the boundary layer is the thinnest because the ...


10

An INS gives your speed & orientation in space, but without reference to what the airmass that you're flying in is doing. The Pitot tube and AOA sensors give speed and pitch orientation in relation to the local airmass, only. An indicated airspeed of 60 knots, measured by the Pitot tube, may correspond to a stationary aircraft pointed into 60 knots of ...


7

The boundary layer grows in thickness as you move aft on a fuselage. It is thinnest near the nose. A pitot tube near the nose only has to protrude a small distance away from the fuselage skin in order to extend out of the boundary layer and into undisturbed air.


7

In analog-instrumented planes, orientation with respect to ground is established by a feature inside the attitude gyro called the erection system which senses the long-term average of the direction of gravity. It then slowly urges the gyro to establish and hold the correct position of the horizon while still indicating short-term excursions from level flight ...


6

Also, to add to Wayne's answer, there are multiple antennas because the computer that processes the data received compares the phase of the signals received from each of them to calculate the direction the signal came from... Because they are separated from one another, any signal received from a point directly in front of them will be received at the same ...


4

Yes, such a system would be beneficial to pilots, ATC, and meteorologists. Pilots are very concerned with meteorological phenomena like icing and turbulence (for safety-of-flight reasons) and winds aloft (for fuel planning purposes). Pilot reports of weather conditions (PIREPs) may be delivered to ATC or Flight Service for local and long-range dissemination. ...


3

The question mentions Speed and Orientation which are broad terms that could include: Group1: (Air Data sensor + computation) IAS - Indicated Air Speed CAS - Calibrated Air Speed EAS - EquivalentAir Speed. TAS - True Air Speed AoA - Angle of Attack (HDG(M) - Magnetic Heading)^^ Group2a : (Inertial/Rate sensor + computation) GS - Ground Speed HDG(T) - ...


3

From standard sensors, we can completely determine attitude Attitude estimation is a mathematically rich domain. If we have sufficiently precise measurements across sufficient degrees of freedom we can completely, and uniquely, solve for the attitude. However, the way any particular application goes about solving it is highly dependent on the goals (...


2

One simple method is that orientation is detected, calibrated, and fixed in place prior to flight. The aircraft can be assumed to be on the ground at systems startup. Gyroscopic instruments are spun up and zeroed while the aircraft is on the ground.


1

The modern solution is to use an Attitude and Horizon Reference System, or AHRS. The system includes both rotation rate sensors and linear accelerometers for all three axes. In the short term, the rotation rate sensors are the key players, but GPS data and magnetometer (magnetic compass) data is used to help seperate acceleration due to turning or changing ...


1

This is a surprisingly hard problem. Initially, the answer was: Just look out of the window. Of course, this became less helpful when flying in clouds. With unmanned aircraft it has become the hard problem I mentioned. The usual recommendation for glider pilots who get sucked up into a cloud is: Let go of stick and rudder, open the speedbrakes and hope for ...


1

I want to understand what is the purpose of doing localization while an aircraft is flying? Knowing where you are means you won't get lost and arrive at your destination instead of literally anywhere else. What sensors are used by the instrument that does this localization of an aircraft? Are there more than one ways to do the localization? Can we do ...


1

I want to understand what is the purpose of doing localization while an aircraft is flying? Well, in general it would be nice to know where you currently are, wouldn't you agree? Even aircraft flying under VFR (Visual Flight Rules) should be able to determine their location, either by looking out of the window and identifying landmarks they know or by ...


1

I worked for Marconi in the 80s. The triple system was created in Rochester in the 1980s. The Triple-redundant was a design and marketing/safety philosophy for the new airbus which was the first fly-by-wire passenger aircraft - Marconi's engineers designed electro-mechanical flight controls for fighter jets, drones, airships, helicopters using the MIL-STD-...


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