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Almost every recreational powerboat on the water today is equipped with an engine cut-off switch—83.2 percent, according to the National Recreational Boating Safety Survey. How often those red lanyards actually get clipped to the captain’s belt, PFD or wrist is anyone’s guess, but it’s infrequent enough that on April 1, 2021, the U.S. Coast Guard began implementing a law requiring all operators of boats less than 26 feet LOA to use one if the boat is so equipped, with exceptions.

If you are not using the kill switch on your boat it’s probably because you find it inconvenient, or even annoying. I’ve been frustrated for years by the very stiff metal clip at the end of many lanyards, and with the way the plastic coating on the end can cling to a stainless steel steering wheel and become tangled. And yet, using the kill switch is a valuable safe-boating habit, as it immediately stops the engines if the captain is thrown from the helm or even overboard.

The wearable alarm fob and hub unit of the Fell MOB+

The wearable alarm fob and hub unit of the Fell MOB+

A wireless system is an alternative that eliminates the lanyard and its associated inconvenience, replacing it with a wearable fob or wristband that sends a signal to a receiver hub on the boat. If the sending unit is submerged—because the captain, a passenger or a pet is overboard—the signal is interrupted, and the hub electronically cuts the engine. Thus untethered, the captain is free to move about the vessel. Because they are triggered by immersion, a wireless system will not shut down the engine if the captain is concussed after being tossed across the cockpit. That’s a disadvantage, but a wireless kill switch is probably better than the one you’re not using at all. Here are three options to consider.

1st Mate Marine Safety and Security System

1st Mate was co-developed by Mercury Marine and Fell Technology to function with up to six Mercury outboard or sterndrive engines with SmartCraft digital technology. The hub mounts within the helm and plugs directly into the boat’s CAN Bus harness. The MOB function sounds an alarm and shuts off the engine when the captain’s fob is submerged, marks the MOB location with GPS on a smartphone app and on vessel multifunction displays, and sends an alert to connected passengers wearing optional fobs, with instructions on how to return to the MOB location. The app can be programmed to send an automatic distress message with coordinates to emergency contacts on shore. The system’s proximity function acts as a theft deterrent by disabling the engines when the captain’s fob is out of range. The Quicksilver 1st Mate Marine Safety and Security System has the same functions and is compatible with up to three Mercury engines without SmartCraft, and most other engine brands. Pricing begins at about $570 for a single-engine kit; additional fobs are $128 each.

ACR’s Olas Guardian is a kill switch and MOB alarm.

ACR’s Olas Guardian is a kill switch and MOB alarm.

Fell MOB+

The MOB+ system is compatible with all outboard and sterndrive brands. The hub unit mounts through a 2-inch hole in the dash and is hardwired directly to the boat’s existing kill switch. The system supports one wireless fob and up to three additional wearable passenger alarm fobs. If the fob goes overboard or is more than 50 feet from the hub, the system sounds an alarm and cuts the engine. After six seconds the engine can be restarted. If a passenger is overboard, an alert sounds and a light flashes on the hub. Price is $200 with one fob; additional fobs are $40 each. 


ACR OLAS Guardian

The OLAS Guardian is a combination wireless kill switch system and MOB alarm for most engine brands. The stainless steel switch mounts through an 18mm hole in the dash, while the hub mounts behind the dash and is hardwired to the boat’s existing system. The hub connects with up to 15 wearable OLAS transmitters (OLAS Tags or OLAS Float-On Lights). Using the OLAS app, one or all of the tags can be designated to trigger just the MOB alarm, or MOB alarm and kill switch, if the tag is submerged more than 50 feet away. (The range may be extended for larger boats.) Using GPS, the app records the MOB alert position and guides the user back to that position. In Solo Mode, the app can send a distress alert to a programmed phone number. Price is $250 with a single wearable tag; additional tags are $80 each. 

This article was originally published in the June 2021 issue.



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