Selected to be a magnetic test site due to its remote location and non-magnetic Portland stone – used on Buckingham Palace – the MOD Portland Bill site is home to the Land Magnetic Range (LMR), a system capable of simulating the Earth’s magnetic field, reducing it to zero or separating it into vertical and horizontal components.
QinetiQ maritime ranges group lead Sam Hill told Naval Technology: “MOD Portland bill is roughly divided into two; magnetic assessment services comprises the land magnetic range, and our ability to both inspect and test magnetic compasses. Then for the EW Calfac [Electronic Warfare Calibration Centre], the calibration facility, that is really for ships and submarines to calibrate their electronic warfare systems.”
On the magnetic testing front, MOD Portland Bill offers several facilities including a compass test centre for the inspection and testing of compasses – this work sees near year-round use as the only accredited centre for compass approval in the UK.
QinetiQ Land Magnetic Range technical manager David Rollett, who oversees the land magnetic range at Portland Bill, told Naval Technology that as well as the geographical benefits, Portland Bill had a unique infrastructure setup. This includes a coil system built around the building and a nine-metre trench allowing sensors to be placed under the objects that are being measured.
Describing the nature of magnetic testing at the site, Rollett said: “It’s a very simple test, but it’s quite a hard test to pass. The magnetic field levels that you’re talking about are effectively just above background levels; they [the sensors] areas sensitive as what a mine could potentially use to target a diver.
“There’s a number of different NATO [North Atlantic Treaty Organization] standards of how to test equipment. If the equipment or the clothing the diver is wearing is going to go right up against the mine threat and it’s going to be potentially touching the mine itself, then we do measurements at potentially a 10cm stand-off from the sensor.”
Two of the most essential facilities at MOD Portland Bill are the Land Magnetic Range and explosive ordnance disposal (EOD) range which are capable of measuring and recording the magnetic signatures of tools and equipment to ensure they do not accidentally trigger explosives when used in the field. A low magnetic signature is key to ensuring that minesweepers do not accidentally set off the mines they are sent to find.
The site also offers a demagnetisation facility for tools and equipment to be used in sensitive locations.
Hill added: “The EOD area is one where we feel that almost direct connection with protecting the lives of individuals in the armed services because we are testing things like the wetsuits that they’re wearing, their gloves, the small boats that they go out in.
“It is very personal, and the team really feel that connection. We will see the EOD teams going out in the UK and detonating unexploded ordnance that’s left over from the world wars and the team will see that on the TV and think we’ve tested what that guy is wearing right now. That’s going towards helping make sure that they’re going to be successful in their task and they’re not going to be injured or killed.”
Electronic Warfare (EW) testing
The other portion of MOD Portland Bill’s capabilities comes on the EW front, with the site’s Electronic Warfare Calibration centre (Calfac) being used by both ships and aircraft to test their Radar Electronic Support Measures (RESM).
David Mitchell, QinetiQ’s EW facility manager at Portland Bill explained: “The facility is called Calfac [it] is an RF [Radio Frequency] transmitter that transmits RF test signals at the Royal Navy platform under test.
“We have a facility here at MOD Portland [Bill] and another MOD QinetiQ managed facility in Scotland up in Applecross. Typically, at Portland, we do the Royal Navy ship platforms and the Scottish facility does the submarine community. Both facilities do the occasional MOD [Ministry of Defence] aircraft.”
QinetiQ also offers a portable Calfac facility, which is designed to reflect the Royal Navy’s ambitions to forward base more ships, allowing the company to bring the testing system to the ship, rather than the other way round. Ultimately, this increases the Royal Navy’s ship availability.
Commenting on bringing testing to the field, Hill added that the Royal Navy is “really keen on us being able to go out to those locations and conduct the testing exactly as we would in the UK; to give them that indicator that they are operating within the parameters that they left the UK with.”
Mitchell continued: “We load the facility with RF test signals. These test signals are loaded on the platform as well and on the surveillance system, so they are easily identified when we transmit a signal.
“The platform usually conducts a 360-degree pivot about five to 10 miles off the Portland Bill. The objective is for the trial is for the platform to, first of all, identify the threat and then establish the bearing accuracy during the pivots.
“They do that 360-degree pivot and they get a pass or fail. The Royal Navy standard is for them to come and see us once a year, or if they’re about to deploy into theatre, they’ll come and pay us a visit to make sure all their surveillance systems are operating correctly.”
The capability can provide representative signals that can mimic targets in different threat situations.
Mitchell added: “We’ve also got the capability to do a complex test signal. They can be produced to simulate a threat like a scanning radar. The platforms have used in the past as a training exercise.
“The ship would actually turn up on the range and the captain wouldn’t tell the crew, what was about to happen, then the facility would transmit a complex threat at them. The ship can then evaluate how the crew respond to that threat.”
The LTPA is a 25-year partnering agreement between the MOD and QinetiQ to deliver Test & Evaluation (T&E) and Training Support Services to all branches of the UK Armed Forces.