Sixty years ago, a violent air battle raged over the skies of Los Angeles – thanks to a runaway drone. BBC Future investigates the ‘Battle of Palmdale’.

A decade after the end of World War II, US fighter planes were scrambled to protect the city of Los Angeles from an unexpected aerial threat. Nearby residents would soon run for cover as rockets rained down on American soil. The threat wasn’t from Soviet intruders. And the pilots did not succeed in their mission. It’s now known by some as the Battle of Palmdale.

This is what happened that Thursday morning exactly 60 years ago – and why the danger is still with us six decades on.

At 11.34am on Thursday 16 August 1956, a special aircraft was launched from a naval air station in California. It was a Grumman F6F Hellcat fighter plane, but refitted as an unmanned vehicle – a drone. Painted bright red, it was about to be used as a target during a missile test. It would take off and fly at a leisurely pace over the Pacific Ocean before being blown to smithereens. At least, that was the plan.

Instead of taking the desired course, the drone stopped responding to commands from its remote controllers and veered southeast, towards the huge city of Los Angeles. It was an immediate danger – a crash in the wrong place could be lethal. Navy officers quickly got on the phone to nearby Oxnard Air Force Base, which had pilots on alert in case of a Russian bomber attack. Two fighters were scrambled to chase the drone, which was now nearing the city.

As the fighter pilots caught up with it, the Hellcat crossed over Los Angeles’ airspace and eventually into an area above unpopulated land. This was their first chance. The pilots’ F-89D Scorpions were equipped with “Mighty Mouse” rockets. They were unguided rockets, armed with an explosive warhead, and could easily take down a drone of the target’s size – if they scored a direct hit.

All along the flight path of the fighters and their bright red quarry lay destruction caused by the F-89s’ wayward salvoes

But there was a problem. The rockets failed to launch when the pilots first attempted to fire them using an automatic system – they would have to switch to manual. But at that point the drone changed its course again, this time back towards Los Angeles. The situation was becoming more urgent. An initial volley of 42 rockets was fired, to no avail. The second plane fired another 42 – still no hit. The drone was now nearing a suburban town called Newhall. Another volley. All the rockets missed.

Finally, as the drone turned in the direction of Palmdale, each plane fired off another round of rockets – this time 30 each. It was their last chance. But every rocket missed; 208 rockets fired and no luck. The drone flew on but ran out of fuel. Eventually, it crashed eight miles east of Palmdale, cutting through electric cables as it ploughed into the ground.

Incredibly, no-one was hurt or killed. But all those rockets hadn’t landed without incident. All along the flight path of the fighters and their bright red quarry lay destruction caused by the F-89s’ wayward salvoes. The newspapers of the day reveal the full extent of the damage.

Fires raged across 350 acres near Newhall – and it took hundreds of firemen to deal with them. Shrapnel burst through windows and into homes. One teenager driving in Palmdale had debris blast through his windshield; luckily he escaped unscathed.

One newspaper wryly wrote up the consequences of an “unintentional bombing attack” while the Los Angeles Times described as best it could the “uncontrolled and dangerous circle” of the drone’s flight.

Many of the rockets hit the ground without exploding, but there was every chance that a slight disturbance could set them off. The US Air Force circulated a description of the weapons to residents in an attempt to avoid any fatal accidents.

In 1997, Merlin and fellow investigator Tony Moore managed to find the Hellcat’s crash site

“It was just such a bizarre story,” says aviation archaeologist Peter Merlin, who stumbled across the incident 20 years ago. He had been reading some old local newspapers from the era while researching aircraft experiments and unexpectedly discovered the tale of the runaway Hellcat.

It wasn’t the first time the remote-controlled Hellcats had been used.  

“They used some of them during atomic bomb tests, to fly the drones into atomic clouds and collect samples,” explains Merlin.

Merlin is fascinated with the number of military aircraft that flew in California at this time. Indeed, he’s amassed a list of 700 crash sites since the 1930s. “Most of them are military or experimental planes,” he says.

In 1997, Merlin and fellow investigator Tony Moore managed to find the Hellcat’s crash site. He says they could even see the scars of damage still left on the repaired powerlines. And in the dirt were obvious pieces of aluminium – with red paint and markings proving it was indeed the aircraft they were looking for. 

Why couldn’t the Air Force fighters shoot the thing down, then, especially after so many attempts? As Doug Barrie of the International Institute for Strategic Studies in London says, the task was a lot easier said than done.

It’s not the easiest thing in the world to do and the more you miss, the harder it gets – Doug Barrie, International Institute for Strategic Studies

“You’ve got these two vehicles moving in three dimensions and you’re firing an unguided rocket which is itself moving along at a fair old lick,” he says.

“It’s not the easiest thing in the world to do and the more you miss, the harder it gets.”

Firing a salvo of rockets into an enemy bomber formation was one thing, it seems, but trying to hit a small single target was quite another, as the Air Force found out that day.

Could something similar happen now? Barrie says it could, but there are more safeguards in place.

For one thing, remotely guided weapons and vehicles are often equipped with self-destruct mechanisms should they go awry.

“And if the data link is lost for any amount of time you have a number of options – one of which is for the UAV to enter a loiter pattern so that it can attempt to reacquire the data link,” says Barrie.

“If that doesn’t happen within enough time and it has enough fuel, it will attempt to return to base.”

The Palmdale incident certainly isn’t the only example of a runaway aircraft littering the annals of military history. In 2009, the Air Force had better success in shooting down a runaway drone – this time a modern Reaper – that nearly flew out of Afghan airspace.

A more tragic case occurred in 1989, when a Soviet pilot ejected from a MiG-23 fighter

And manned aircraft can sometimes wriggle out of human control, too. In 1970, a Convair F-106 jet went into a spin over Montana, prompting the pilot to eject. Amazingly, the plane stabilised and landed in a snowy field. It was in such good condition that, following repairs, it was returned to service. It earned the nickname “The Cornfield Bomber”.

But a more tragic case occurred in 1989, when a Soviet pilot ejected from a MiG-23 fighter that seemed to have suffered power loss. At that point the jet was in Polish airspace, but following the ejection it continued to fly on autopilot towards the West.

It flew right over East and then West Germany. US Air Force pilots were scrambled from a base in the Netherlands and told to shoot the MiG down over the North Sea. But before it reached that point, the wayward aircraft ran low on fuel, turned south and eventually crashed into a house – killing a Belgian teenager.

“Technology,” says Barrie, “is fallible”. And it probably always will be.

But Merlin, who is more aware than most of how accident-prone the development of these machines can be, points out that failures have always been a part of aviation history.

“The area where I live is full of aviation history – experimental vehicles, X-planes, the development of the Space Shuttle – so many different things were done out here,” he says.

“There was a very steep learning curve so crash sites kind of represent that legacy.”

Thankfully, the Battle of Palmdale, as it was later dubbed, did not result in any deaths. But it certainly was extraordinary. A contest between man and a machine with a mind of its own, 60 years ago – in the bright blue skies above Los Angeles.

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