SIMS: Technology that puts crew safety first

There’s no doubt about it. Lifeboating is a hazardous activity. Our volunteer crews put their lives on the line every time they launch their lifeboats, particularly in rough weather and heavy seas.

A Shannon lifeboat on a training exercise at sea

Photo: RNLI/Nigel Millard

Imagine trying to move around a lifeboat to perform your duties as the rain lashes down, the wind howls and the waves crash around you. There is a greater risk of injury in conditions like this. And if a crew member becomes injured, it can jeopardise the whole rescue mission.

That’s where SIMS comes in – an RNLI innovation in marine engineering that has transformed the way our crews operate their lifeboats, dramatically improving their safety.

What is SIMS?

Aptly described as ‘Safety In My Seat’ by our Tenby crew, SIMS actually stands for Systems and Information Management System.

It’s an electronic integrated bridge system that allows the crew to monitor, operate and control many of the lifeboat’s functions directly from their shock-absorbing seats.

These functions include: the navigation of the lifeboat, including direction finding, radar and charting; radio communications and CCTV; and the mechanics of the lifeboat including the engines, bilge and electrics.

In addition to improving crew safety, SIMS allows better task sharing among the crew and negates the need for lots of separate systems and equipment, saving space and reducing weight.

This cutting-edge technology was originally developed in conjunction with ship systems integrator Servowatch for our Tamar class all-weather lifeboat, making the Tamar our most sophisticated and safest lifeboat of the time.

And for our latest class of lifeboat, the Shannon, SIMS was developed in conjunction with software and solutions company SCISYS and communication solutions provider Savox.

What SIMS means to the crew

11% (25) of our 236 volunteer lifeboat crews now benefit from safer shouts, thanks to SIMS.

Tenby were the first lifeboat crew to receive a Tamar, the Haydn Miller, back in 2006. And today they are among 23 crews with Tamar class lifeboats.

Earlier this year, Dungeness and Exmouth were the first two crews to welcome their new Shannon class lifeboats. And to date another 15 lifeboat stations have been earmarked to receive one.

Estate Agent and Volunteer Crew Member Robert John has been volunteering on the Tenby crew for 19 years. He has seen first-hand the difference SIMS has made to lifesaving at sea.

‘As a Navigator, controlling SIMS has become second nature.

‘Eight minutes ago I was asleep in my bed, yet I have already plotted a course to the casualty thanks to the fast and intuitive layout of the SIMS system.

‘The Coxswain stands ready at the USP (Upper Steering Position), looking at the course on the chart in front of him – the information has been instantly transferred to his display screen.

‘A "Thanks Rob" in my headphones is all I need to hear from the Coxswain’s busy position to know he has all the information he needs to steer a safe course to the casualty.

‘As the Tamar thunders down the slipway and joins the charted route, up pops our ETA along with other vital information that the Coastguard will need in our next radio transmission.

‘Just a few minutes in and we hear some faint calls from the casualty’s radio. The SIMS DF (direction finding) screen is checked as we home in on his VHF signal. We have an accurate bearing and, not long after, the radar screen again confirms we are on the right course.

‘It has been known for casualties to give out the wrong position in their haste. By integrating our navigation and detection equipment, SIMS gives us the best possible chance of a successful and timely outcome.

‘It’s not easy operating computer equipment bouncing in a seat, but this system has got to be the best out there.’

So how does SIMS work?

There are six SIMS workstations on board the Tamar and the Shannon at the following crew positions: Coxswain, Helm, Navigator 1, Navigator 2, Mechanic, Upper Steering Position (USP).

The first five positions are located within the wheelhouse and the USP is up on deck.

Each workstation is made up of the following three elements.


  • A 15-inch LCD flat screen with a minimum resolution of 1024 x 768 pixels.
  • The screen has a viewing angle of 120° and supports a full palette of colours for both day and night operations.
  • It is backlit for operation in direct sunlight and fully dimmable in darkness.

Trackball pod

  • The trackball pod allows access to the various SIMS functions.
  • It acts in the same way as a computer mouse.
  • The trackball and buttons are easier to use than a keyboard or touch screen in rough weather.
  • With a keyboard and touch screen, the keys or screen can inadvertently be knocked, leading to control and software issues. Plus keyboards take up space and require stowage.
  • The whole trackball pod is waterproof and has a bespoke ergonomic design.
  • For most crew positions on our all-weather lifeboats it is fitted to the right-hand seat arm.


  • Waterproof headsets with two earpieces and a microphone boom allow easier and clearer communication between the crew.


The following screens represent each of the SIMS functions:

  1. Helm
  2. VHF
  3. MF
  4. Radar
  5. Chart
  6. DF (Direction Finder)
  7. Engine
  8. CCTV
  9. Hatch
  10. HYDR (Hydraulics)
  11. Bilge
  12. SW (Sea water)
  13. SWBD (Switchboard)
  14. Fuel
  15. Fire

Who does what?

Every crew member can access all of the SIMS functions to see the status of the lifeboat, but each function is commanded by one crew member at a time.

Responsibility for each of the functions is determined by the crew member’s position onboard. But crew members can also take over the control of a function from each other.

The coxswain is the only one who can command all of the functions, but only if he or she takes over the control of them from the other crew members.

The coxswain is also the only one who can shut SIMS down and power off the lifeboat when back at the lifeboat station.

It’s important to note that although SIMS provides all the information the crew need to operate the lifeboat, all decisions are still made by the crew, not by SIMS.

What if SIMS malfunctions?

When lives are at risk, SIMS needs to be reliable and able to withstand extreme weather and sea conditions.

The high-tech system is made with tough, rugged and salt water-resistant hardware that is designed specifically for durability and reliability in harsh environments.

It’s built using solid-state technology, meaning it has no moving parts such as hard disk drives. This makes it more robust and shock-resistant.

SIMS uses an Ethernet local area network (LAN) architecture for fast and reliable communication between multiple workstations.

It’s designed with a high degree of redundancy, incorporating a chain of back-up systems that reduce the risk of complete system failure.

And in the highly unlikely event that all SIMS back-ups fail, the lifeboat can still be operated using conventional methods.

No bells and whistles

Despite its intelligence and the complexity underneath, the SIMS user interface is deliberately plain and simple for speed and ease of use.

Time is of the essence when out on a shout. Crew need to access and view the information they need as quickly, easily and clearly as possible, especially if they’ve been called out in the middle of the night.

So there are no touch screens, which are more susceptible to accuracy problems and damage. There are no fancy 3D maps, which can clutter the screen and hide potentially important information.

The buttons are big for crews’ gloved hands. And the background colour of the screen display is a neutral light yellow for clarity and readability.

The future of SIMS

Crew safety is of paramount importance and we are always striving to improve it.

But the majority of our 236 volunteer lifeboat crews are operating older classes of lifeboats that don’t have the innovative SIMS technology. So our electrical and electronic engineers have been working with our lifeboat crews to develop our own scalable version of SIMS.

Developed entirely in-house, RNLI SIMS has allowed us to bring a modular version of SIMS to our all-weather and inshore lifeboats alike, dramatically cutting the cost of this system.

Its innovative and flexible design means RNLI SIMS can provide anything from just a single workstation with a single function such as charts, to up to six workstations and more covering the same functionality as that on the Tamar and Shannon.

More than 80 D class inshore lifeboats have been fitted with RNLI SIMS since January 2013. They currently have a single workstation that provides helm and chart functions.

RNLI SIMS on our B class inshore lifeboats goes further with dual workstations providing helm, radar, chart, direction finder and switchboard functions. Rollout to our B class fleet started in January 2014 with 10 boats fitted to date.

Twelve of our all-weather lifeboats have also been fitted with RNLI SIMS so far, with a full rollout to our Severn and Trent class lifeboats planned before the end of 2014.

These lifeboats will initially have a single workstation with chart functionality to replace their current ageing chart system. But in time more RNLI SIMS workstations and functions could be integrated to improve the lifeboats’ safety, reliability and efficiency at sea.

Learn it once, use it everywhere

Rolling RNLI SIMS out to more classes of lifeboats means our crews will not only be safer and their lifeboats more reliable, they’ll benefit from sustainable training too.

Our two training boats now have RNLI SIMS fitted with four workstations each so that crew can be trained with the same equipment as they use on their own lifeboats back at station.

Once they know how to use RNLI SIMS on one lifeboat, crews could potentially operate any class of lifeboat.

This could mean that whenever they need a relief boat, they won’t necessarily have to have the same class of lifeboat, easing the control of our relief fleet.

It will allow for greater flexibility among our crews and stations across the UK and the Republic of Ireland.

And it will reduce training time and costs, meaning we can make better use of your donations.

Speaking about the sustainability of SIMS, Steve Austen, former Head of Engineering Support at the RNLI, says: ‘Allowing crews to monitor and control all major boat systems while protected in shock mitigation seats makes a major contribution to their safety.

‘Building on the work carried out in partnership with contractors for the Tamar and Shannon, the in-house version of SIMS retains these features, yet provides a system that is modular, scalable and at a greatly reduced cost.

‘This means the RNLI can continue developing the system as old equipment becomes obsolete and new equipment becomes available, allowing us to introduce the latest innovations in lifesaving in a timely and sustainable way.’

SIMS will be installed on future lifeboats as they’re built in the All-weather Lifeboat Centre in Poole, Dorset. Help us build the centre that will secure the future of lifesaving at sea.