To joystick or not to joystick – that is the question! We weigh up the pros and cons of this boating phenomenon…
The key benefit and most attractive feature of IPS (Inboard Performance System) has to be in close quarters manoeuvring allowing you to control and direct the boat at low speeds, and with just one hand. The fact that the pods are well spread means that they exert plenty of leverage but the real advantage is their ability to operate completely independently of each other in terms of direction and thrust, and for the control of that to be simplified into a single joystick control. It means that from the helm you simply push or twist the joystick the way you want the boat to go (forward, back, sideways, swivel on the spot) and computers translate that into the correct commands –a major attraction for the novice sailor or those who regularly use crowded marinas.
IMPROVED INTERIOR SPACE
The second huge advantage is packaging in medium-sized boats. IPS allows the engines to be sited further aft, but still cope with the power requirements – up to 900hp each. As a result, you can now buy sportscruisers under 50ft with massive full beam master cabins such as the Princess V48, Fairline Targa 48, Sunseeker San Remo and so on. It also helps a bit with flybridge boats, so boats like the new Prestige 420 flybridge have more accommodation (and a full beam master cabin) than you’d typically find on a flybridge boat of this size.
IPS gives good efficiency compared with shaft drive options, reducing fuel consumption and allowing faster speeds.
One of the other benefits of IPS is that it gives a very smooth and quiet operation, making time spent on board as comfortable and noise-free as possible.
IPS is often more expensive than conventional shaft drive but few manufacturers offer both options so it’s difficult to put an exact figure on it. As a rule of thumb expect that an IPS system will add around 10 to 15 per cent of the cost of an average boat, but this may well come down in time.
Many boat owners feel that the forward-facing propellers, as in the Volvo-Penta IPS system, could be more vulnerable to debris in the water than more conventional systems.
If you hit a rock at high cruising speed with an outdrive, it will tilt. Hit it with a shaft and you’re likely to do some damage, possibly serious. Hit it with an IPS and you stand a real chance of the unit shearing off entirely. In fact many are designed to sheer off to avoid causing further damage to the boat.
Ultimately, IPS gives you easier, safer and more predictable handling, a smoother, quieter ride, more performance or economy and more space in your
boat than with a traditional shaft drive. And for the mid-range boat owner, it seems these pros far outweigh the perceived cons. Easy, then, to see why it’s fast becoming an increasingly popular option, especially on craft between 45 and 55ft.
Been There, Used That…
“Pods are great innovations and obviously a lot of R&D have gone into them by the various engine manufacturers. I have taught and done deliveries on vessels with both Volvo’s IPS and Cummins Zeus Pod drives but, for me, who grew up on shaft and outdrive boats, it feels slightly gimmicky – a nod to the XBox generation and they are an expensive option.”
“For a novice who can afford them it’s fine as they have nothing to compare it to and so it becomes the propulsion of choice by default.”
“They allow greater interior space and tend to be quieter and allow higher top speeds and are arguably more fuel efficient, but this efficiency is considerably affected by excessive fouling compared to traditional props/shafts arrangement.”
“They have slightly higher service costs and being full of high value parts I imagine repair bills will mount considerably as the boat ages. People’s biggest concern seems to be fears over hitting underwater objects and the pods shearing off by design. Although the cost of replacing a pod would obviously be great, a shaft or outdrive boat hitting an underwater obstruction could have far more catastrophic consequences. My favourite aspect of them, though, is the ability to hold station (within 3m) via GPS (when that option is fitted, of course!).”
“My biggest dislike is when manoeuvring in very strong winds there is simply not enough power through the joystick option to counter it and one has to (quickly) reengage the throttle controllers to get adequate power to the pods. To be fair, this scenario would be a rarity to the average owner and the more precise docking capabilities in normal conditions far outweigh this concern.”
Read more about Mark Taylor in our 1 to 1 interview.