Smooth and efficient operation of the National Airspace System depends on timely execution of flight-related events. Weather can severely disrupt the carefully planned flight schedules at a hub airport and impact travelers through out the country. In particular, a snowstorm may cause substantial perturbation in the departure of aircraft due to the need for deicing prior to takeoff. The additional time needed for an aircraft to be deiced, including time in queue, is highly nonlinear and difficult to predict.
In general, the deicing process works as follows. An airplane is assigned to a deicing pad to be deiced. A deicing pad has multiple positions where the aircraft can be deiced; the positions can be of different sizes. (Some airports have more than one deicing pad, each containing several positions.) An airplane is driven or towed to the queue of the assigned deicing pad, and waits for a sufficiently large position to become available. Once an appropriate position is open, the leading aircraft in the queue taxis into that position. The airplane is then sprayed with a mix of chemicals combined to accomplish the rapid melting of ice, snow, or freezing rain that has accumulated on the aircraft. Supplementary chemicals may be sprayed to prevent additional accumulation. Once an aircraft is in a deicing position, the time required to spray the aircraft is a function of its size, the experienced efficiency of the specific deicing position, the accumulation of ice/snow on the aircraft, and the severity of the snowstorm/weather event.
The Deicing Decision Support Tool (DST) estimates the amount of time an aircraft takes to go through deicing. This timing information maximizes the efficiency of deicing operations by minimizing wait times for aircraft in the queue for treatment, thus enabling the airport, airlines, and air traffic controllers to work together to minimize delays and cancellation of flights by optimizing airport and flight resources.
Some of the variables addressed in this system include aircraft size; size and capacity of each deicing position; the number of deicing positions available in each deicing pad; the number of such pads at the airport; the operational availability of each deicing position; experience-based data on time required at a specific deicing position to deice aircraft makes and models; and the number, size, and type of aircraft waiting to be deiced.
The time estimate can also be updated continuously as the aircraft waits to be deiced. This information can be displayed directly to the aircraft; for example, by means of a signboard adjacent to the queue, or by radio to the pilots of queued aircraft. Alternatively or additionally, the outputs of the system can be provided to airport, airline, or air traffic control personnel for their use in assigning aircraft to the various deicing pads. In addition, the software can be used for long-term planning or to provide input to other planning-oriented aviation tools. Simulations can be run on future flight schedules and deicing resources. If the invention predicts excessive delays, additional deicing resources can be allocated to mitigate delay, or flights can be cancelled or delayed to reflect the realistic expectation of departure time. What-if analyses also can be examined.