gambit
PROFESSIONAL
- Joined
- Apr 28, 2009
- Messages
- 28,569
- Reaction score
- 148
- Country
- Location
True...From a sensor perspective, land and sea MUST be treated differently, and the lower the altitude, the greater the difficulties in making a nap-of-the-earth (NOE) flight.
The problem for an NOE flight lies in making a reliable estimation of what is the terrain X distance ahead of the aircraft. A hill is not a wave. A hill is static, a wave is not. For example, since fuel is finite and maneuvers consumes fuel, a determination must be made in terms of altitude. Fly high enough and you can treat this moving mass as if it is a static mass. Fly low enough, and if you fly really low enough, then the wave can literally swat you out of flight in really rough sea. The solution is to electronically 'ride' the wave in its form, as in aircraft nose up/down, but then that lead back to the problem of maneuvers consumes fuel.
Land is not so problematic. With sufficient geographic intelligence, an NOE flight can be a combination of sensor returns correlates with memorized topographic terrain features. Since hills, mountains, forests, and buildings do not move, sensor reach can be further ahead, making even more precise estimations as to how the flight would be, saving fuel.
A sophisticated NOE sensor and flight controls system will be able to compensate between land and sea seamlessly. If the sensor detect calm sea, the system can treat the sea surface as if it is land. The threshold for what is 'calm' depends on the designer. If the sensor detects higher sea states, based upon the Douglas Sea Scale, the system can either fly to a higher altitude where it can treat the sea surface like land, but if that altitude threatens detection, the flight can resort to flying in a rise/descent motion. It all depends on that maximum altitude limit programmed not to breach to avoid detection by enemy radars.
