They are NOT very similar, although they may have a streamlined aerofoil cross-section (to reduce drag).
Bilge keels (& most keels) serve to stabilise the vessels course and to prevent drift to leeward; so in some ways are similar to an aircrafts's fin (UK) or vertical stabilizer (US).
The secondary function of a bilge keel is to allow the boat to settle in a stable manner at low tide.
because they both make things fly
Triplane
A triplane is an aeronautical term that refers to an airplane with three similar-sized wings or pairs of wings. These wings are stacked one above the other to provide increased lift and maneuverability. Triplanes were popular during World War I for their agility and climb rate.
Airplane? What airplane? My paper airplane wings weigh less than 8 grams.
The importance of wings is critical to an airplane, they produce lift that can sustain the airplane in the air.
An airplane with two wings on either side is called a biplane.
They are on the wings
The two wings of the airplane are made of aluminum.
Because they are both use for flying.
biplane
Airplane cargo
An airplane