To the editor:In a recent article (“Trucking a boat,” Issue No. 96, March/April 1999) about trucking boats overland, I discussed the two types of trailers available: “screw pad” and submersible hydraulic. I more or less dismissed out of hand the use of hydraulic trailers for long hauls. My comments, incidentally, were all based on my own observations, not related second hand. These hydraulic trailers were invented by Thomas Brownell of Brownell Systems Inc. in 1962. Since then the company has built 185 of them, of which the majority are designed for boatyard work (they don’t have the right kind of suspension to go at highway speeds). However, they have also built 50 “air ride” versions that are intended for highway use, and of these maybe as many as a dozen are regularly used for long-distance deliveries (Brownell has two devoted to this) while the rest are used for local hauling with occasional long highway hauls thrown in. I received a polite, but nevertheless aggrieved, letter from not just Thomas Brownell, the president of Brownell Systems, but also his daughter Cynthia (the trucking manager), the factory foreman, two crane operators, and four truck drivers! They disputed just about every one of the assertions I made regarding this type of trailer and invited me to visit their plant for a demonstration of their trailers at work. I accepted the invitation and recently went down to Mattapoisett, Mass., where the trailers are made. I have to say they sure showed me! So let’s look at the issues I raised: “The boat loading process makes it harder to precisely locate the boat on the trailer.” The one tremendous advantage of these trailers (which I did point out) is that they require no crane to load and unload a boat (a major cost savings) and can even take a boat right out of the water. But if you load from the water, particularly if there is any crosswind or tide, you basically have to get the boat more or less in position, whip the hydraulic pads up to stabilize it, and get it out of the water. The boat may well not be in the optimal position for trucking. This is what I had in mind. Of course, what I overlooked is that, if this is the case, once the trailer is out of the water all the driver has to do to reposition the boat is set it down and put it where he wants it. This will probably take no more than 15 to 20 minutes. It is “harder to customize the location of the supports for the boat.” With a screw-pad trailer the boat is set in place and the truck driver determines the optimum position for support (in relation to bulkheads, etc.) and then effectively builds a cradle under the boat, with as many pads as he thinks fit, placed wherever he thinks they are most appropriate (they are sometimes referred to as “erector set” trailers). The hydraulic trailer has either four (two on each side) or six (three on each side) hinged arms with hydraulic rams and pads on top. The pads are set on supports that can be moved in and out of the arms; nevertheless, the final location of the pads is clearly limited by the fact that the hinges are fixed. However, what I did not appreciate is the amount of thought and experimentation that has gone into these hinges (Brownell is on its third generation of hinges). By sliding the pads in or out of the arms, the amount by which the arms are raised to contact the boat changes. This changes the extent to which the pad ends up toward the center or the outside of the trailer. The pads themselves are fully toggled (will hinge in any direction). The result is that a skillful operator can put these pads in a wide range of places. There is not the same flexibility as with a screw-pad trailer, particularly on the smaller four pad trailers, but there is a great deal more than I had appreciated. “It is harder to ensure that everything is solidly fastened down to resist damage from the vibration, shocks and winds experienced on cross-country journeys at highway speeds” and “this is a piece of equipment with many, many moving parts that is not really suited to long highway runs.” I had in mind here the thought that the oblique angle of the hydraulic arms (because of the way they hinge up), as opposed to the vertical structure of a screw-pad trailer, combined with the potential for sponginess or leaks in the hydraulic system (as opposed to the mechanical rigidity of screw pads, once set up) could result in a softening of the support for the boat, and therefore the boat vibrating around and getting damaged. In reality, the wide support base of the hydraulic hinges and other features of design, coupled with check valves in the hydraulic system, mean that once the pads are in place this is a pretty rigid system that is maintained without hydraulic pressure. It seems about the only thing I got right was my statement that “this is a high-dollar piece of equipment.” Typically, these trailers cost two to three times as much as a screw-pad trailer, which means that quotes for a long-distance haul may be higher than the competition. Set against this is the fact that it will quite likely be possible to avoid crane or travel hoist charges, and the boat loading and unloading process (particularly the loading process) is likely to take just a fraction of the time it takes with a screw-pad trailer. What’s more, there are hauls, such as when picking up or dropping off a boat in a backyard, when the hydraulic trailer is the only way to get the boat in and out. The hydraulic trailers do, however, have a couple of limitations for long hauls that I failed to note. The first is that they have shorter beds than most screw-pad trailers, which limits the size of mast that can be carried alongside the trailer. Longer masts have to be loaded on the deck of the boat, which is not a good way to haul a mast over long distances (it increases the risk of damage to both the boat and the mast). Second, although these trailers can be set up in boatyard work such that a boat’s keel is as little as two inches off the road, yet for “over-the-road” work the keel will be at least eight to 12 inches off the road, which is several inches higher than many screw-pad trailers and may well prove to be a problem when height is critical. At the end of the day, both Thomas and Cynthia Brownell stressed, as did a number of other trucking companies, that irrespective of what trailer is used to haul a boat, the key thing is the knowledge and experience of the driver. All of Brownell’s drivers have been with the company for years, and all are boat owners, something which the company encourages by providing free hauling and winter storage. Having watched them at work, I would have no qualms in letting them handle my boat for either a short or a long haul.