Airboats are popular shallow draft vessels that are used by private individuals for fishing and general waterway use. They are also used by commercial tour operators for excursions in areas of natural beauty such as the Everglades. The giant fan at the back is capable of propelling racing airboats at speeds up to 130 mph across very shallow waterways. These boats can move from water to land or ice and back again easily. But what happens if you can’t turn around … can an airboat go in reverse to get unstuck?
Most airboats cannot go in reverse. To make an airboat go in reverse it needs to be equipped with a reversible propeller which can cause several problems when used and can even lead to the sinking of the airboat. However, there is at least one company that made an airboat with a reversible propeller. This company used a Jon boat for the hull and attached a fan at the stern with a reversible propeller so the boat could go in reverse. These airboats are no longer available.
Reversing an airboat isn’t a easy as it sounds
Being able to move from one type of terrain to another, and from deep water to shallow water, or from water to land, you can imagine that sometimes an airboat might get stuck and be incapable of moving forward. So, shouldn’t an airboat be able to move in reverse?
It may seem like a good idea to give an airboat with the capability of reversing but unfortunately most airboats cannot go in reverse, and for some very good reasons! Certainly the large commercial airboats that we see across the US which are used for tours and airboat rides are not capable of moving in reverse and if they were there would a lot more accidents and lot of unhappy passengers.
Why is this?
Well, not only is it dangerous to reverse a large airboat (for reasons I will cover later) but the only means available for doing it would make the ride very uncomfortable as well. You see it all has to do with the functionality of the propeller.
Why you can’t reverse most airboats
Unlike a road vehicle, which has gears, an airboat has no gears. The only moving parts on an airboat are the giant fan and rudders at the boat’s rear.
The fan is made up of a propeller positioned inside a safety cage, like a desktop or standing fan you may have in your home or office. Air is generated by the propeller in the fan and is pushed outward away from the boat thus creating thrust.
The air generated by the propeller is manipulated by the rudders placed directly behind the fan (or in front of it, depending on which way you look at it). If you want to learn more about how an airboat works read this article.
As the fan only generates air behind the boat this means the boat can only move forward; the airboat is pushed forward by the thrust of the air that is being pushed away from the boat at its rear.
In order for an airboat to move in reverse you would need to reverse the propeller. Obviously this is not possible in most cases because the propeller is fixed in place and situated behind a safety cage.
However, even if you did reverse the propeller this would cause more problems that it solves.
Possible problems from adding reverse to an airboat
So why don’t airboats have reverse?
It could have something to do with the fact that reversing an airboat is not always a good idea and, if you did it on a very large airboat, you may get into trouble fairly quickly.
As I have already mentioned, in order to reverse an airboat you must be able to reverse the propeller. This means that instead of air being generated behind the boat so it pushes the boat forward, the air is being generated and pushed to the front of the boat.
Can you see the potential problems this could cause?
Firstly, as the pilot/driver of the airboat is seated just in front of the fan at the stern of the airboat he will feel the full blast of the air as it is generated by the fan. Apart from losing his hat, sunglasses and possibly his shirt, on larger airboats it is unlikely the driver would be able to remain in his seat!
The passengers onboard the airboat would also feel the brunt of the air and anything that was not secured on the boat would be likely blown off.
But let’s say you overcame that problem by shielding the driver and passengers from the air in some way. The next problem you would have to overcome would be steering.
Rudders at the back of the fan are used to redirect the air that is being generated by the propeller and are the means by which the driver maneuvers the airboat. With these rudders at the back of the fan they can only manipulate the air when it is being generated away from the boat. To be able to redirect the air when in reverse there would need to be a completely separate set of rudders inside the boat positioned on the other side of the fan. This is obviously impractical.
A third problem you would encounter when reversing an airboat is water intake on the boat. Airboats are flat bottom vessels that resemble large Jon boats. The stern of the boat is not designed to cut through water. On a mod-V Jon boat, for example, the front of the boat is curved upwards and has a slightly v-shaped bottom (only at the front though) to help it better cut through chop. But the back of the boat has a flat transom that sits relatively low to the water due to the boat’s low freeboard.
As an airboat has the same type of hull design as a mod-v Jon boat it also has a transom, at the stern, that is flat and unsuitable for cutting through water.
If the fan on a large airboat where to push the boat in reverse with powerful thrust, (and the driver, passengers and everything onboard were lucky enough to stay in the boat), the transom of the vessel would probably be forced down into the water and the boat would start to sink.
So you can see that there are 3 basic problems with reversing an airboat. To recap they are:
- Air from the propeller would be generated forward instead of backwards and would hit the driver, passengers and probably blow everything off the boat.
- Steering would be difficult unless an additional set of rudders were placed in the boat on the other side of the fan.
- The airboat would probably take on water as the transom is flat and not deigned to cut through chop/waves/water.
However, there is one company that did the inconceivable and made an airboat that is capable of going in reverse.
Airboat going in reverse (video)
How Oakie Gator made a reversible airboat
So how did Okie Gator overcome all the problems with making a reversible airboat that I outlined above?
Well, they didn’t.
Though to be fair to them their airboats weer capable of being reversed but they encountered all the problems I have already mentioned. Plus, they never made any large airboats.
Oakie Gator airboats that have reverse capability are reasonably small vessels that have a hull that is essentially a Jon boat? This means the fan that is fitted to the vessel will not create too much thrust to force the stern into the water when reversing.
But what about the rest of the problems?
Well, they created reverse by introducing a way to change the pitch of the blade while it remained in motion. They basically made their propeller reversible. Although this allows the airboat to move in reverse, and actually works really well as a brake (which airboats don’t have), it still must generate forward thrust by blowing air towards the front of the boat and thus has the same problems that come with that as I mentioned above.
The people on the airboat will feel the thrust of the air being pushed towards the front of the boat when the fan is in reverse.
Although you may be able to pick up a used Oakie Gator airboat you won’t be able to get a new one. This company no longer exists which should tell you everything you need to know about reversing an airboat!