We all know that best safety practice dictates that the helmsman should have the kill cord attached to his person while the boat is under power. But how many of us actually do this? I admit I hardly ever do, as it's so restrictive when managing a Mac, but I've been giving the subject some thought of late.

Kill cords are mainly associated with fast power boats, RIBs, etc. With these craft there is a very real danger of being physically thrown off when powering at speed in choppy seas, or maybe hitting another boat's wake at an injudicious angle. If the boat runs away under power it will typically travel in a circle, arriving back to hit and likely fatally injure the crew that were just ejected. When driving, the helmsman will be sitting at the helm, not moving around, and so the kill cord is not a restriction. This is a kill cord's most critical usage.

However, our Macs are not driven like that. Even at full power, the likely-hood of being tossed out of the cockpit of an X or M seems pretty slight. (A 19 is perhaps a bigger risk, with its smaller hull, shallower cockpit, and slightly more power-boat-like handling. As a 19 owner, this is one aspect that's concerned me a bit.) In "normal" use, the motor on a Mac is used in the same way as the inboard in a conventional yacht, and I don't see helmsmen on those boats wearing kill cords.

But a kill cord can still be a valuable safety feature when single-handing, where the ever-present risk of falling overboard with no-one to pick you up is a significant danger. Clipping on is of course a primary precaution, but again how many of us single-handers actually clip on all the time? Say you're motoring away from your mooring, and you step forward onto the coach roof to pull in a fender. You don't clip on - the water's flat, and you've done it loads of times - but this time you slip. Oops! Your lifejacket inflates, but your boat is merrily chugging on to who-knows-where, probably ending up wrecking itself as well as other boats, and leaving you far behind. A kill cord would have saved the situation, but you couldn't have used it because you've had to move too far from the helm.

Is there a solution? Well maybe - I've been looking at wireless kill cords, and wondering whether to invest in one. Does anyone have any knowledge or experience of these things?

From what I can find, there's not many options available, and none are cheap. I've found three - CoastKey, MOB+, and Autotether. All work on the principle of a base unit that activates the motor's kill button, and a wireless fob you keep on your person. If the fob moves out of wireless range, or gets submerged, the base unit triggers the kill switch. You can also press a button on the fob to manually cut the motor.

CoastKey is an astronomic £550, which I've pretty much discounted on cost alone.

MOB+ is £240 from Force4 (here), plus £20 - £30 extra if you want a wrist strap or lanyard for the fob.

Autotether is available for £199 here, complete.

Initially I liked the look of Autotether, it needs no wiring-in, it physically replaces the kill-cord tag in attaching to the kill button, and can eject itself from the button with an internal solenoid. However, I've found several reviews describing it as cheaply built and liable to corrode after quite a short time. It's also been around a good few years, and sites that Google list as selling it no longer do. The link above is the only UK retailer I could find still stocking it, so maybe it hasn't done very well. It also runs entirely on AAA batteries, which is a bit worrying for a safety-critical device. Given what it is, it's actually very expensive.

The MOB+ is a bit more expensive, but appears to be a better-engineered device. It does however need physically mounting, and wiring into the control unit (or wherever the kill button is). I'm going to investigate how I might mount this in the cockpit of my 19, and if it seems feasible I'm very tempted to splash out.

It does seem to me that one of these devices gives you all the safety of a regular kill cord and more, allowing you to move away from the helm but still know the engine will stop if you involuntarily "abandon ship". What does anyone else think - can anyone speak from experience?