It is said that the best defense is a great offense. This means instead of only sitting back in your foxhole and waiting to be attacked, sometimes the best way to protect yourself is to go outside the wire and attack your enemy. This would be getting inside the enemy’s OODA Loop.
What is the OODA (Observe, Orient, Decide, Act) Loop? It’s the process that occurs in our day-to-day lives when we observe something occurring, orient ourselves to the situation by identifying it as a problem, decide a course of action, and then acting upon that decision. When you get inside an enemy’s OODA Loop, you make them continually need to reorient and make a new decision, trying to eliminate their time for the appropriate reaction.
Ambushing a Patrol
An example is ambushing an enemy patrol before it can attack you. The enemy knows where your defenses are. They prepare an assault to try to penetrate your perimeter. They leave their safe zone to come attack you. You get inside their decision making process by attacking them on their way to you. The enemy now goes on defense, something they were not prepared for, and because of it, you now have the advantage as they react to what you are doing.
Axel Foley Disrupts Would-be Robbers
Remember the movie Beverly Hills Cop when Eddie Murphy, who plays Axel Foley, foils a robbery of a nightclub? In one scene, Foley and a couple of detectives are in this club and Foley OBSERVES something that is out of place, two men who walk into the bar wearing long coats when it is Summer in Los Angeles. Foley (ORIENTS) identifies that these men are doing something out of the norm, likely there to rob the club and hiding weapons under their coats. He (DECIDES) makes a plan with the other detectives to thwart the robbery and they each move to better positions near the bad guys and prepare to react. Before the two robbers get to decide when they will make their move, Foley forces their hand. When they brandish their weapons to get everyone’s attention, Foley and the other officers quickly take both bad guys down. These two robbers had an idea that they would rob the bar, but had no plan to counter any obstacles, the officers. So they did not have time to decide and react, and were taken down easily. See clip of Axel Disrupting a Robbery
The Best Defense is a Good Offense
Now back to “the best defense is a great offense” phrase. In air defense, the best defense would be an excellent radar. Early warning systems are very important to the survival of friendly troops, equipment, and airfields from attacking aircraft and even vehicles. When the enemy plans to fly to your position and attack, if you have radar and can detect them far away from your position, you have time to scramble aircraft to disrupt their plans.
1932 – Germany Rebuilding Their Aircraft Industry
In 1932 while traveling through Europe, Churchill observed Germany in the rebuilding process of their aircraft industry. To prepare for future aggression from Germany, the Royal Air Force (RAF) performed experiments with large number of their aircraft. There were an estimated 350 bombers and fighters testing whether the RAF could stop bomber aircraft from reaching London. By using their Royal Observer Corps, a civil defense organization that would identify and report aircraft over Great Britain, and fighter aircraft to intercept the bombers, most of the bomber aircraft never saw one fighter before reaching their targets. Following this dismal performance, during the next drill the fighter aircraft were given very detailed information about the bomber’s path, targets and times, and still nearly 70% reached their targets in London. A different solution would need to be identified if the destruction of London from aircraft attacking from over the English Channel was to be avoided.
With the United Kingdom’s research in the early 1930’s of radio frequency by men like Robert Watt and Arnold Wilkins, it was determined that shortwave radio signals bounced off aircraft. This was enough to identify direction, but not distance, to a target. Adding pulse signals to the transmission and measuring the time it took to bounce of the target and returned allowed the RAF to determine range and angle.
Their first known tracking of aircraft was on June 17, 1935. The radar system picked up returns and tracked a seaplane 17 miles away from their transmitter location. This date is considered the birthdate of radar in the United Kingdom. By October the distance of detecting aircraft had increased to 80 miles.
Chain Home – the first early warning radar network in the world
This early warning system was the solution Britain needed for the defense of London. As war clouds gathered, the likelihood of air raids from Germany and the threat of invasion by air and sea drove a major effort in applying science and technology to British defenses. In 1935, plans were put in place to build a network of radio towers 20 miles apart along the east coast of Britain, and by the summer of 1937 they were in place.
On September 1, 1939, Nazi Germany invaded Poland. Two days later, Great Britain and France declared war on Germany and World War II began. Twenty-one Chain Home (CH) stations were in place along the eastern seaboard. The CH system could determine high flying targets well over France, well before they reached the English Channel, providing up to 20 minutes of early warning.
With the addition to this system of Identification Friend or Foe (IFF), also developed by Arnold Wilkins, the radio operators could then identify if the blips on the screens were friendly forces or enemy bombers.
The Chain Home Radar Installations
A CH station consisted of four 360 foot tall steel towers separated by 180 feet. Strung between the towers were vertical feed cables. Between these vertical cables were eight half-wave dipoles spaced ½ a wavelength apart. Chain Home would send out a burst of radio energy toward a target and then calculated the time it took for that signal to return. Instead of steering a radio beam like a narrow flashlight and detecting when a target lights up, like today’s radar systems do, the Chain Home antennas were stationary and illuminated large areas like a spotlight. Direction to the target was determined by adjusting a knob that would minimize the blip and a scale to determine the angle. Based on the strength of the return, the size of the attacking force could then be assessed.
More about these towers as vertical arrays were described some by Duotech Services’ Silas Gibbs in his video, “Antenna Arrays Part 1”.
Britain Disrupting Germany’s OODA Loop
With the early warning of approaching aircraft, fighters could then launch and intercept German bombers well ahead of their intended targets. This was Great Britain getting inside of the Luftwaffe’s’ OODA Loop. It was highly effective in the defense during the Battle of Britain. The Luftwaffe lost nearly 1700 aircraft and almost all its crews, while Britain lost just over 900 and save most of their pilots. The costly air battle caused the Germans to abandon their plans to invade England.
Radar systems are essential to early detection of targets on land and in the air. Today’s defensive radar systems are much more advanced than the Chain Home, but the purpose behind both are the same: provide advanced warning of an approaching target in order for you to gain an advantage.
AN/FPS-117 Long-Range Radar System
Instead of the CH’s four 360 foot towers that have cable spanning between the towers to transmit and receive a signal and limited to scanning a distance of 80 miles, today’s long range air search radar, like the AN/FPS-117, is a phased array antenna. It provides 360 degree, 3D target information in real time, and can adjust elevation scanning using an electronic steered beam. It has a range of 287 miles.
Aircraft Also Require Radar for Early Detection
Mechanical radar systems like the F-16‘s AN/APG-66/68 are mechanically scanned radar systems. They antenna array is rotated and shifted using motorized components to scan the horizon, or below, to identify threats and track them. Radar systems that use electronically scanned arrays do not require mechanical parts to move the beam to a particular zone. These make them more efficient because they have less moving parts that could fail.
Radar systems have proven their worth throughout history, winning wars, saving lives and property. From the world’s first stationary defensive radar system, Chain Home, to the more modern long range mobile systems of today, there will always be a need to see ahead of your position and let you know when the bad guy is approaching.