AirRouteOperator.LowFlightSafetyInput Property
Gets or sets an input operator that gives a raster with safety factors for nap-of-the-earth flight.
Syntax
public Operator LowFlightSafetyInput { get; set; }Property Value
Remarks
The raster should normally represent terrain concealment by Float safety factors that must be non-negative. The default factor is 1.0 which is used outside the raster, or where the raster contains Undefined values, or if there is no input raster at all.
Like the similar safety factors that can be associated with airspaces, the values in this raster will be multiplied with the true local speed of the aircraft to produce a fictional local speed, which is used to calculate a fictional travel time that defines the cost of the route. This will encourage the AirRouteOperator to let the route pass through concealed areas. See also Aircraft Routing.
In most use cases, the safety factors in the raster should be at least 1.0. For example, we can let the exposed area over a ridge get the normal safety factor 1.0, while a more concealed area in a valley gets a higher safety factor 3.0. Now imagine there is a forbidden airspace in the valley and another straddling the ridge. If the aircraft route goes over the airspace on the ridge, the aircraft must climb from its nap-of-the-earth height, so the local safety factor there will come from the HighFlightSafety factor, by default 1.0; in other words, the airspace on the ridge makes no difference. And if the aircraft route goes over the airspace in the valley, the local safety factor will become 1.0 for the same reason, which also makes sense, because the airspace could be high enough that the aircraft would no longer be concealed when passing over it. (Of course, the airspace might also have a modest harmless height, but since concealment information is available only for nap-of-the-earth height, the operator assumes the worst.)
Now, consider what would happen if we had chosen to represent the concealed valley by the normal safety factor 1.0 and the exposed ridge by a safety factor less than 1.0, say 0.5. It is still true that the operator would use the HighFlightSafety for routes that go over the airspaces, but this would fool the operator into thinking that the airspace in the valley can be flown over with no extra risk, and that the airspace on the ridge can be flown over with better safety than the bare ridge.
In some use cases, though, it can make sense to use safety factors less than 1.0 in the raster. For example, roads could be given such a safety factor, because when flying over a road, the safety should increase with height, unlike our normal use case where higher flight makes the aircraft less concealed from enemies.
Platforms
Windows, Linux, Android