“If you know the enemy and know yourself, you need not fear the result of a hundred battles.”
SUN TZU, 512 BC
At the start of World War II, radar technology was in its infancy. Defence forces had to fight blind until it was often too late to act against aerial strikes. However powerful your air force was, the element of surprise was the deciding factor. They were sitting ducks. Reconnaissance and survey flights were the only way to get a timely response.
Rapid development of radar technology was of great importance in WWII and a determining factor in the Allied victory. In the Battle of Britain, the Royal Air Force had aircraft equipped with radars. Combined with ground stations that were capable of detecting German aerial incursions, radar was a huge advantage. It is believed that Britain has gone so far to keep its progress in radar technology a secret that it spread propaganda about British pilots eating a lot of carrots to see better.
Some historians regard that capability to detect planes and ships at a great distance as the most significant factor that shaped the war. But the top brass was reluctant at first to use the technology. After all, being able to view a tiny blip a of radio wave on a screen compared to an actual visual image was not a very convincing argument. The Army delayed employing the technology till the very last minute but ultimately made the right call.
Today information is in abundance and more accessible than ever. Satellites can give us spatial resolution of objects smaller than 0.3 m across and will soon provide global internet coverage. We can spy on terrorists and listen to their discussions in real time. We are able to detect interstellar objects flying through our solar system and tell what chemical compounds are on their surface. Generals can gather data in real time from battlefields thousands of miles away. Any type of enemy and warfare can be explored remotely.
All but one. Chemical attack and CBRN in general are considered unfeasible from the long-range detection point of view. The consensus is that you ‘have to be in it to know it.’ Best-case scenario is to detect a chemical cloud a few hundred metres away, if the weather is favourable. We have settled for a few minutes’ warning time for personnel to mask and suit up as a great achievement. Sarin can be produced and deployed by adversaries with limited resources. Yet it is easier to detect a hundred-million-dollar aircraft flying at high speed than a few hundred dollars’ worth of chemical agent sneaking up on you.
Most of the CBRN units today rely on point detectors – with no information from a distance. One might argue that there is remote detection on drones, but that is redolent of survey flights in WWII trying to spot the enemy approaching – with one difference, that the drone must move across the cloud to ‘see’ it. And once it does, it is unable to return to the unit before decontamination, placing a further burden on battlefield logistics and resource management. Not forgetting that the enemy will probably have a substantial radar system to spot the drones.
From a distance
Indeed, there are passive stand-off detectors which play a role in situational awareness via visualisation and fast scanning. Once near the cloud, they are very useful indeed but only if we are not talking about a few hundred metres maximum.
Sensitivity decreases rapidly with distance. Physics is to blame. Physical limits simply do not allow these detectors to behave as an early warning system. In bad weather passive systems are not usable. In WWII, if conditions permitted, binoculars were a great tool for spotting an upcoming attack – if not from far away, at least they provided information. Enemy planes still flew at night, however – and in bad weather as well, thereby avoiding interception.
How can we assume today’s enemies will release a chemical cloud only when the background is at the right temperature? Or when humidity is low? Or, expect them to avoid a release if urban structures don’t allow for a wide view to collect enough energy? When the first doctrines were expounded a chemical attack was assumed to be of substantial size. The smallest desirable detection limit was to be able to detect a 50-m cloud at a 5-km distance. Nobody could do that then – so we settled for a 300-m cloud at a 500-m distance.
Modern conflicts are fought with precision strikes, and chemical warfare is no different. The enemy is getting smaller and nastier. Combine this with the fact that the cloud expands travelling downwind, and you have a perfect storm. As is often stated, it’s a poor man’s WMD.
The answer is active stand-off detection. Seeing the aircraft with ‘passive’ binoculars is never a total solution, but radar could easily penetrate bad weather and ‘see’ the aircraft from far away. Similarly, an active chemical stand-off detector emitting laser energy can obtain a reflection and bring back actionable results.
Good outcomes in the early development of active detection systems were achieved in various projects in the US, India, Czechoslovakia and other countries. Slovakia was the first country to adopt active stand-off detectors for its armed forces and still use them actively, and not just on NATO missions and exercises.
Active stand-off technology has its limits and drawbacks, but if somebody tells you it harms the eyes or can be detected by enemy forces, don’t believe him. Nowadays only a few private companies and a small group of pioneers are pushing the limits further, and the results are very tangible. Passing through fog or smoke and still being able to detect tiny amounts of chemicals kilometres away is a reality for active stand-off detection today. If there is local rainfall which you need to scan behind, it is not a problem. While there are no laboratory results, advanced equipment made to military standards is getting answers in real environments.
In high humidity or dry weather, the same sensitivity can be obtained and for same CWAs, up to a hundred times better than any passive approach. Narrow beams of light in very short pulses can penetrate harsh weather and gather data and information in a way no other technology can. A mere 100 g of chemical vapour can be detected more than 5 km away.
Taking good tactical decisions is vital for immediate action and to minimise personnel exposure. It entails piecing together the whole picture with minimal resources. Identification will normally take longer than detection, but not if you use an active stand-off detector. Whether used to discover the presence or absence of chemical hazards, lasers can provide vast area coverage and identification at the same time. Active stand-off chemical detection technology is ready. If we need to guard the big secret again, we may need to resort to old propaganda and order in more carrots!
Image: Harsh winter trials.