- Yes
- No
Hi, I suggest today the addition of terrain following radars
Terrain-following radars are devices that allow an aircraft to follow the terrain while maintaining a constant altitude above it. This technology allows insertion into hostile territory at very low altitude and high speed, which reduces the risk of detection by the adversary. When this flight mode is engaged, the pilot no longer has to touch the controls of his aircraft because the onboard computer takes care of maintaining the altitude (some of these radars also maintain a certain speed deemed optimal for maintaining altitude)
TFR systems work by scanning a radar beam vertically in front of the aircraft and comparing the range and angle of the radar reflections to a pre-computed ideal manoeuvring curve. By comparing the distance between the terrain and the ideal curve, the system calculates a manoeuvre that will make the aircraft clear the terrain by a pre-selected distance, often on the order of 100 metres (330 ft). Using TFR allows an aircraft to automatically follow terrain at very low levels and high speeds.
The concept was initially developed at the Cornell Aeronautical Laboratory in the 1950s. It was first built in production form starting in 1959 by Ferranti for use with the TSR-2 aircraft, flying for the first time in an English Electric Canberra testbed in 1962. While the TSR-2 project was ultimately abandoned, the concept was widely deployed in 1960s and 70s strike aircraft and interdictors, including the General Dynamics F-111, Panavia Tornado, Mirage 2000-D and Sukhoi Su-24. The wider introduction of stealth aircraft technologies through the 1990s has led to a reduction in low-altitude flight as a solution to the problem of avoiding anti-aircraft weapons and the technique is no longer common. Most aircraft of this class have since retired although the Su-24, Mirage 2000-D and Tornado remain in use in some numbers.
Technology
The system works by transmitting a radar signal toward the ground in front of the aircraft while scanning up and down. This signal is sent in short pulses, and the time it takes for these pulses to return helps measure the distance to the terrain. A sensor determines the angle of this return relative to the aircraft.
At the same time, a generator produces a varying voltage representing a preferred flight path for the aircraft, resembling a ski ramp that is flat under the aircraft and curves upward in front. This curve shows the path the aircraft would follow if it were maneuvering at a constant force. The desired distance between the aircraft and the ground is set by the pilot.
The radar pulses are sent quickly, and when the signal returns, the system compares the return angle with that of the ideal curve. If the voltage is positive, the terrain is above the curve; otherwise, it is below. This difference is called the “angle error.”
The system records the largest angle errors during a complete scan and adjusts the aircraft’s pitch accordingly to maintain the desired clearance altitude. The result is a flight path that follows the terrain while maintaining a constant load.
However, the system may cause the aircraft to climb too high over hills, a phenomenon known as “ballooning.” To correct this, an additional function causes the aircraft to climb faster, reaching the desired clearance altitude earlier.
The radar cannot detect hills hidden behind other hills, limiting its capability. Additionally, it struggles over water, where signals are less accurate. In these cases, the system relies on a radio altimeter.
The system generally works in relative terms, without considering the absolute altitudes of objects. However, it can also calculate the exact height of an object relative to the aircraft, and from this, determine the clearance margin.
In game :
In-game, terrain following radar could be implemented (for aircraft with this technology) easily by adding a new mode to the SAS, this would allow this feature to be activated simply. This mode would be mainly usable in battle simulator, although its use in realistic is not impossible (passage at low altitude above the battlefields in tank battle to drop different weapons for example). The addition of such a system would make it possible to recreate various combat scenarios and would ensure a certain security for strategic bombers which are the planes most threatened by anti-aircraft defenses but also by other planes.
Some in-game aircraft are equipped with TFR in reality:
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F-111
The F-111 is equipped with the AN/APQ-110, this TFR allows terrain following between 200 and 1000 feet at supersonic speed. It should be noted that the higher the speed the higher the altitude (the system’s reaction time does not allow it to be at maximum speed at minimum altitude) -
Panavia Tornado (IDS / GR1)
The Panavia Tornado is equipped with the Ferranti Terrain-Following Radar, this TFR allows terrain following at 200 feet at Mach 0.9. -
Mirage 2000-D
The Mirage 2000-D is equipped with the Antilope V, this TFR allows terrain following at 200 feet at Mach 0.9. -
A-6E
The A-6E is equipped with the AN/APQ-148, this TFR allows terrain following between 200 and 500 feet near Mach 0.85. -
Buccaneer
The Buccaneer is equipped with the AN/APN-171, this TFR allow terrain following between 200 and 330 feet at Mach 0.8
Video
(https://www.youtube.com/watch?v=UdCqlh0Ig6g)
Promo video for the F-111 TFR system (terrain following radar) (youtube.com)
Strike and Terrain Following Radar - YouTube
Sources
- Jane’s All the World’s Aircraft :
- Aviation Week & Space Technology : Aviation Week Network - Homepage | Aviation Week Network
- FlightGlobal : FlightGlobal | Pioneering aviation news and insight
- Thales Group
- Raytheon Technologies
- GlobalSecurity.org
- Military & Aerospace Electronics : 7. Military & Aerospace Electronics
A-6E manual : CNAF M-3710.7 (navy.mil)
Tornado manual: http://www.avialogs.com/index.php/aircraft/europe-and-consortiums/panavia/tornado/aer1f-pa200-1-panavia-200-tornado-flight-manual-italian-series-aircraft.html
