F-117 pitot tubes
Source: YouTube. Also a look at the FLIR and DLIR.
F-22 pitot tubes
Source: AIR-SCENE UK.
Incorporation of those pitot probes were a cost savings measure. They are also a dominant RCS signature source in the forward and side sectors. The original ATF proposal was for a flush air data system that would have cost many $ ...
The SSR antennas are labeled ATC L and ATC R (two at the top, two at the bottom).
Both SSR and TCAS systems use the same communication protocol and use the same frequencies (1030 and 1090 MHz). They could well use the same antennas. However for best performance, SSR antennas are omnidirectional and TCAS antennas favor some sector, ...
Short answer: They're antenna(s) for the onboard VHF radio(s).
Airplanes aren't actually required to have radios. But, if you want to fly into certain classes of airspace, you must have at least one VHF radio on board, to communicate with air traffic control. A lot of planes (in fact, I would say the majority of them) actually have two radios installed. ...
The image below labels each of the antennas. To summarize based on your groupings:
A: Multi-Role Electronically Scanned Array (MESA) made by Northrup Grumman. It has a similar role to the large rotating dome on the E-3 in tracking airborne targets. Instead of being rotated mechanically, it can be electronically scanned.
B: Communications/Navigation, GPS, ...
They are omni-directional: Anyone, in any direction, can hear the broadcast.
They are analog (non-digital), AM signals, so there are no bits, and thinking in terms of kbps or data-rate doesn't make sense.
These have similar transmission power to many AM radio stations. Do you have safety concerns about local AM radio stations that broadcast baseball ...
Glideslope antennas are those U shaped stubby 3 prong fork things that look like heating elements for a water heater. That's a 75 Mhz Marker Beacon antenna. I have revised this post. I thought it was just a VHF antenna, mainly because almost all Marker Beacon antennas you see out there these days are faired-in blade antennas, but the comment by @Gerry got ...
What type of antennas are used today for tower-aircraft comms? Are they directional or omni-directional?
The antennas are omni-directional however on the aircraft the mounting is important to maintain line of site and the FAA covers it in this AC. This is in reference to <12,500LB aircraft but the logic applies to all planes.
d. VHF Com 1 should be ...
Mod Depth (more commonly called modulation index in electrical engineering) is the amount a carrier signal is modulated. Mod depth has nothing to do with antenna configuration and is set by the transmitter (or more precisely the modulator). The log periodic antenna controls the width of the various beams. A larger antenna means a smaller beam and smaller ...
As this film shows with brilliant simpliciy, the drag of a round wire is almost 10 times the drag of the same thickness streamlined shape.
Biplanes use streamline rod for flying and landing wires because of this. There is enough flying/landing wire on a biplane for it to make a huge difference.
On a long antenna wire however, there really isn't a ...
It is an HF (High Frequency) antenna. It is used for aircraft to communicate on overseas flights. VHF (Very High Frequency) airband radios are used for normal local and cross country flights.
For a radio to transmit effectively, the internal components of the radio and the external (to the radio) antennae both have to match the frequency used for the ...
It’s a high-frequency antenna, used mostly on flights traveling across seas and oceans, where there tends to be areas without VHF and UHF coverage. This was the case on older aircraft, most newer ones have a smaller hidden one on the tail-fin.
Note that the assertion "It can only receive signal if the transmitting antenna is not exactly in front of it" is wrong. The most sensitive direction for receiving is in fact exactly in front of the antenna, so if the incoming beam is directly in line with the yagi shafts, the maximum signal strength will be received.
A parabolic antenna would be bigger ...
First, both parabolic & Yagi antennas are "directional" in that their main lobe is designed to have high gain in a limited direction. this is because all antennas have to trade the width of their main beam(s) with the amount of gain in that beam. you can either put a little power everywhere or a lot of power in one direction.
that being said the picture ...
If you go to www.skyvector.com and zoom in to MRB
(easy to enter a flight from KOKV to KMRB to find it quick)
Select the World VFR view, and you will see no navaids at that location.
Select the Enroute L-29 view, and you will see no navaids at that location.
So no, it is not a type of currently used navigation aid.
If you peruse the Instrument approaches ...
It would seem the ATC outputs pretty low power!
This is from a General Dynamics Air Traffic Control radio data sheet
RF Output Power:
Low Power Transmitter 2-12 Watts with co-site filter,
2-20 Watts with out co-site filter
High Power Transmitter 12-35 Watts with co-site
filter, 12-50 without filter