Blow up Boats: Part I

by Howard Carte III

Inflatable boats suit today's lifestyle. You can store one in a closet or under a bed, carry it to the water in a small car or motorcycle, launch it without ramp jams and bounce it off rocks that mash "hard shell" craft. You can paddle, row, sail or power these handy craft where conventional boaters can't reach.

Fishermen who mix small streams, ponds, remote coves and other protected waters find small kayak and dinghy inflatables ideal. River runners appreciate larger donut rafts. Sportboat runabouts suit surf launches, water-skiing and more open water. Inflatables have crossed the Atlantic and, of course, kept pilots and seamen afloat after planes and ocean-going ships sank.

Europeans have used inflatables for years, but these hardy craft have, except for river rafters, been slow to catch on in America. Some remember the problems with military-surplus craft designed for one-time emergency use rather than extended life. I still remember my first days in a W.W.II four man life raft that, I discovered, was about right for two people. Others have heard about or suffered unfortunate experiences with the "el cheapo" type translucent pool-toy craft that should be limited to kid's play -- if that.

Durability is no longer a problem with today's improved plastics and Kelvin, graphite and reinforcing materials tough enough to master the Colorado, Green, Snake and other mighty rivers.

However, there's a huge difference in size and price between commercial inflatables large enough to hold a vehicle and tiny backpacker's kayak or dinghies aimed at casual family use. Form follows function so your first step is simple. You need to carefully define your needs. Then select a boat class. After that you can narrow your choice to a single boat.

Your power options require close attention. Inflatable kayaks move nicely with double paddles. They don't paddle well with canoe paddles because, like all inflatables, the width of the tube prohibits an in-line stroke. They do cost less than most other choices and offer good separation for anglers.

Dinghies, donut-shape "life rafts," tend to spin if paddled, but move fairly well with oars. That is, if you can use oars longer than the toy-size some sell. Most dinks have molded-in oarlocks. Since the oarlock and, in most designs, the seat and floorboards all flex, don't expect much power. This is the reason most river runners use add-on rigid rowing frames. Molded-in motor mounts handle smaller motors up to four horsepower or so, but you need rigid motor mounts to handle larger motors. Actually, you don't need these if you don't mind poking along. Some dinks add sail options that are not a bad choice for first time and casual sailors. All of these options perform more efficiently if you find a dink with solid floorboards which stiffen the boat.

 If you want power ,check sportboats with solid transoms. Tubes that extend past the transom and floorboards let you use larger motors if you do not mind the higher prices in this class. You do save money if you realize sportboats run nicely with motors about half the manufacturer's suggested maximum.

Some sportboats come with inflatable or rigid keels which let you turn without skidding. Others such as the excellent, and expensive, Avon Seariders® use rigid lower hulls which improve waterski performance and offshore handling even more. Smaller sportboats seem an excellent choice for family boaters. Some sportboats offer sail options; all row more effectively than dinghies.

Unfortunately, the suggested capacity for inflatables is misleading, as tubes eat up quite a lot of space on all inflatables. Sportboats have less useable space between the transom and bow than you would expect from their length because of the tube extensions needed on the stern to support the weight of the motor. The best way to size an inflatable is to try to fit your party and your gear into any inflatable you consider in the store. Sit for a few minutes and your knees may suggest a bigger boat.

As a rule, a nine foot or longer inflatable kayak lets one large or two small people fish in reasonable comfort. Ten or 12 foot kayaks allow two paddlers to tote a fairly inactive child or enough duffel for an overnight camp. Dinghies need to be at least four by six feet inside the tubes for two, and even here flycasters find them snug. Sportboats or dinks with motors should have four by seven or eight feet of free space inside the tubes for two.

If you heft inflatables in the same class and size you find surprising weight variations. Except for ultra-light backpackers dinghies that can put hike-in fishermen on remote ponds, opt for the heavier boat. Extra weight means thicker tubes, multiple layers, stronger transoms and longer hull life. It also costs more. However, better quality inflatables will, if given considered care, last several times longer than lightweights so they often seem less expensive on a "cost per use" basis. Heavyweights tend to have larger diameter tubes which support heavier loads.

Hull Materials

Hulls divide into two types. Unsupported hulls, usually made from PVC plastic, work reasonably well for kayaks and small dinghies. They weigh and cost less than supported hulls which usually sandwich a fabric such as tough 1000-denier polyester with a tough, abrasion and UV resistant outer layer such as hypalon® and a flexible inner lining such as neoprene. Supported hulls are a must on sportboats and river rafts and improve hull life on kayaks and dinghies. As always, price rises with quality.


Fittings that fail seem the major cause of complaints about low cost inflatables. Look for valves with no-return features to ease inflation as they allow you to rest. Heavy-duty black plastic or plastic and brass valves seem the choice. Clear plastic tube-type valves work fairly well on seats and such. Tape them down with duct tape if you find them on hull tubes.

Some dinghies and sportboats use wood or aluminum floorboards and/or seats. Sportboats use wooden transoms. Any time you attach a flexible hull to rigid supports you can get friction and abrasion. Watch such spots carefully and patch them before the outer coating wears through to the fabric. Wood requires periodic refinishing too. 

Other fittings such as grab-line attachments, molded-in oarlocks and motor mounts should be carefully examined. As a rule heavier weights and higher prices mean increased durability. So if you compare two or three boats, quality is evident and you know which to buy. This seems a good reason to search out a source which offers more than one boatline.