Anti-icing system for aircraft

An anti-icing apparatus for an aircraft, said apparatus comprising:

• a. an aircraft structure comprising a metal skin section with a leading edge and with a first forwardly facing leading edge surface portion which is that portion of said skin section more susceptible to icing, and a second surface portion which extends rearwardly from the first leading edge surface portion to receive air flow from said first leading edge surface portion and which is less susceptible to icing;
• b. said first leading edge surface portion being formed with a plurality of through air openings which are located over a substantial surface area of said first leading edge surface portion and which lead from an inside location of said skin section to an outside location of said skin section;
• c. air flow means to deliver pressurized hot air to said inside location to cause said pressurized hot air to flow outwardly through said air openings over said first surface portion, heating said first surface portions and adjacent boundary layer flow to inhibit icing on said first surface portion, said hot air to then flow rearwardly over said second surface portion at a flow volume and temperature sufficient to also inhibit icing on said second surface portion;
• d. baffle means positioned at said inside location of said skin section to provide at least first and second air chambers to receive said pressurized hot air and deliver said pressurized hot air through first and second skin regions adjacent to said first and second chambers, respectively, said first surface region being positioned to experience lower outside pressure levels during flight than said second surface region, said air flow means being arranged to supply said hot pressurized air to said first chamber, check valve means operatively positioned between said first and second chambers to permit hot pressurized air to flow from said first chamber to said second chamber, but to prevent reverse flow from said second chamber to said first chamber, whereby during periods when pressurized hot air is not delivered to said first chamber, outside air is prevented from flowing into said second chamber to said first chamber.

An anti-icing apparatus for an aircraft, said apparatus comprising:

• a. an aircraft structure comprising a metal skin section with a leading edge and with a first forwardly facing leading edge surface portion which is that portion of said skin section more susceptible to icing and which is directly exposed to ambient atmosphere, and a second surface portion which extends rearwardly from the first leading edge surface portion to receive air flow from said first leading edge surface portion and which is less susceptible to icing;
• b. said first leading edge surface portion being formed with a plurality of through air openings which are located over a substantial surface area of said first leading edge surface portion and which lead from an inside location of said skin section to an outside location of said skin section, said air openings having sufficiently small width dimensions so as not to cause substantial disturbance to boundary layer flow over said first forwardly facing leading edge surface, and said openings being spaced sufficiently close together so as to permit adequate flow of de-icing air through said openings to accomplish de-icing;
• c. air flow means to deliver pressurized hot air to said inside location to cause said pressurized hot air to flow outwardly through said air openings over said first surface portion, heating said first surface portions and adjacent boundary layer flow to inhibit icing on said first surface portion, said hot air to then flow rearwardly over said second surface portion at a flow volume and temperature sufficient to also inhibit icing on said second surface portion.