Planes that can land on water are not an everyday sight for many people, and their application and the distinction of various types of aircraft in this category may seem a little confusing. There are a few terms that are used when referring to these aircraft, and we will discuss seaplanes and floatplanes and whether there are differences between these two aircraft.
A seaplane is a type of aircraft that is capable of landing and taking off from water. The floatplane is a type of seaplane that uses pontoons to land on the water surface, rather than landing on the hull of the aircraft as is typical in flying boats, which are another type of seaplane.
Planes that are made to land on the water have a significantly different feature set to those that are only made to land on solid ground. Seaplanes and floatplanes are the two types of aircraft we will explain to clarify their differences.
What Is A Seaplane?
A seaplane is any fixed-wing plane that has the capability of landing and taking off from a body of water, not limited to the sea only.
Seaplanes as a concept have been around for some time. As far back as 1876, a French inventor, Alphonse Penaud, registered a patent for a plane design with a boat hull and retractable landing gear.
The first seaplane was built by Austrian designer Wilhelm Kress in 1901 but it failed to take off. The first successful powered seaplane flight wasn’t until 1910 by Frenchman Henri Fabre. Since that time, designs have improved, and the versatility of the aircraft brought with it many benefits.
Seaplanes were used extensively throughout World War II and played a vital role in an era when there were not many landing strips and airfields to get troops and supplies into war zones.
The end of the war saw the use of commercial aircraft take off as an industry, resulting in the building of many land-based airports and airfields, which reduced the need for seaplanes in many locations.
Seaplane is the main category of this type of aircraft, but the following sub-categories are included in this group.
- Flying boats
- Amphibious aircraft
What Is A Floatplane?
A floatplane is a sub-type of seaplane with certain characteristics that separate them from other seaplanes. These aircraft are also referred to as pontoon planes, which may be a more accurate description for these aircraft.
Floatplanes are usually aircraft that were originally designed to land on solid ground but have been modified for water take-offs and landings.
The modification that allows these aircraft to use bodies of water as landing surfaces is pontoons mounted to the struts where the wheels were previously mounted, under the fuselage of the aircraft.
The pontoons are slender floats that are shaped to cut through the water and provide buoyancy to keep the aircraft afloat in the water.
The boat shape of the pontoons reduces the drag of the water on the surface of the pontoon to make landing and take-offs smooth. If the pontoons were not shaped this way, the resistance of the water would rip them from the plane on landing or prevent the aircraft from taking off.
The pontoons on the floatplane are the only part of the aircraft that comes into contact with the water. The hull of a floatplane is not designed to sit in the water or contact the surface of the water in any way.
The aircraft that are modified into floatplanes are normally light aircraft, which limits their carrying capacity for people and cargo. Floatplanes can come in single and twin-engine varieties.
They are mostly used to access remote locations where terrestrial landing options are limited, but there is an abundance of water. Isolated regions such as Alaska rely heavily on these types of aircraft to bring in supplies and transport people to and from these regions.
The de Havilland Canada DHC-3 Otter is an example of a floatplane that is used extensively in Canada and Alaska.
What Is A Flying Boat?
A flying boat is another type of seaplane, and the name “seaplane” is often used interchangeably with this type of aircraft, even though it is a sub-class of the seaplane category.
The name “flying boat” is an indication of the main difference between these aircraft and floatplanes.
Flying boats land on the water on the hull of the aircraft rather than pontoons or floats. They often have small floats on each wing to prevent the wings from dipping into the water during take-offs and landings.
Flying boats are generally larger aircraft than floatplanes, giving them the capacity to carry larger, heavier loads and more passengers. Because they are larger aircraft, they are usually configured with two or more engines and also require a larger body of water for landing than floatplanes.
Land-based airfields and large cargo planes have mostly taken over the role of flying boats as people and cargo carriers, but these aircraft are still used around island archipelagos and hard-to-reach remote locations in Canada and Alaska.
Many flying boats have been repurposed as firefighting aircraft. Their ability to land on the water allows a modification where they can scoop up water as they fly low over the water. The water is stored in tanks and can be dumped over runaway forest fires as a means to bring them back under control.
The Short S23 “C” class is a four-engine, medium-range example of a flying boat.
What Is An Amphibious Aircraft?
An amphibious aircraft is a type of seaplane that has the capability to land and take-off from the land or from water.
Many seaplanes only have the capability to land on water. Some floatplanes have removable pontoons, which can be replaced with wheels to make them able to land on solid surfaces again.
Some seaplanes have retractable wheels built into their hull or the pontoons, which gives these aircraft the ability to land on water or solid land without modifying the aircraft. These types of seaplanes are called amphibious aircraft.
The added weight of retractable wheels limits the range and carrying capacity of these aircraft compared to land only or water only planes.
The additional complexity of these aircraft and the fact that they are slower and more expensive to maintain than other seaplane aircraft has limited their popularity, despite the advantage of their versatility.
The Canadair CL-215 is an example of an amphibious seaplane that was built as a firefighting aircraft.
Flying boats were made mostly obsolete by the proliferation of land-based airfields that were built subsequent to Word War II.
Amphibious aircraft are simply too expensive and inefficient to be of much value in mainstream aviation, which limits their use to specialized functions.
Of the three types of seaplanes, the floatplane is the version that is currently still in wide use, particularly in remote locations. These aircraft are cheap to run and are small enough to land in small bodies of water, making them ideal in this role for remote locations that have plenty of water.