A single FPV was enough to bring down the railway bridge by detonating explosives placed by the ... More Russians
116th Mechanized Brigade 'Sky Ryders'A video released on June 27th shows an unusual FPV attack – one which destroyed a railway bridge north of Kupyansk which the Russians were using to transport supplies. It is an impressive strike by the ‘Sky Ryders’ unit, which succeeded by detonating explosives which the Russians had placed in case they needed to demolish the bridge.
This is yet another example of how the extreme precision offered by FPV strikes more than compensates for the small payload. Much of the time the drone does not destroy the target, but rather, in a phrase coined by TX Hammes in 2016, it just ‘brings the detonator’ so the target destroys itself. We have seen tmany examples in the current conflict, including a number of other bridge demolitions.
Bridge Dropping The Easy Way
‘Bridge dropping’ has always been one of the most challenging bombing missions. The target is small and even a near miss can have little effect. Only a direct hit on a bridge support will bring it down. In WWII, American B-24 Liberators dropped 1,219 bombs on the Myitnge bridge in Burma and scored just 18 hits, and the Japanese were able to repair damage.
During the Vietnam war the vital Thanh Hoa bridge resisted many attempts to destroy it, including one massive raid in 1965 involving 30 F-105D Thunderchiefs dropping eight 750-pound bombs apiece. Even the new Walleye guided bombs failed to make an impact.
Massive air strikes like this one failed to bring down the Thanh Hoa bridge during the conflict in ... More Vietnam
USAFBy the time of the 1991 Gulf War the USAF was using laser-guided 2,000-pound bombs for bridge busting missions. Each mission typically involved a team of four F-111F Aardvark aircraft working together. The aircraft made successive passes, dropping one bomb at a time until the bridge was destroyed. The combination of laser precision and one-ton bombs was very effective, but required low-altitude bombing and was only possible because Iraqi air defenses had been neutralized.
Ukraine does not have the luxury of this type of airpower, and faces strong air defence. Instead, the ‘Sky Ryders’ unit of the 116th Mechanized Brigade deployed a single FPV drone with a warhead of perhaps 4 pounds. The operator maneuvers the drone underneath the bridge and locates a demolition charge placed by the Russians.
Bridges are often prepared for demolition where there is a risk that they might fall into enemy hands. This is a complex process taking hours, so explosives need to be emplaced ahead of time. If the enemy is already advancing on a bridge it may be too late. (In one action in 2022, when remote detonation failed Ukrainian engineer Vitalii Skakun sacrificed himself by blowing up Henichesk Bridge manually, significantly slowing the Russian advance).
A reconnaissance drone likely noted the exact position of the explosive charge so the FPV operator could fly straight to it. Video from an overwatch drone shows the charge is detonated and the entire span destroyed.
An FPV flown by the elite Birds of Magyar unit flies through bridge supports on its way to setting ... More off demolition charges
Birds of MagyarThis is not by any means a unique case. A similar video from April released by the renowned Birds of Magyar shows the destruction of another Russian bridge by the same method. In this case the FPV is specified as being controlled by a fiber optic cable – this ensures that communications are not lost when the drone dips out of sight, which can affect a radio link.
The Russians have also used the same tactic. Videos on social media from March claim to show a bridge east of Sudzha demolished by an FPV which set off explosives positioned at the base of the concrete supports, though it is not clear how much damage was done. Another video last month is claimed to show a bridge in northern Siversk similarly damaged by a Russian FPV setting off demolition charges. In this case the entire span has been downed.
Detonating Everything
In fact, the Russians might be said to have originated the tactic of using small drones to bring the detonator with their series of sabotage attacks against Ukrainian ammunition depots in 2017. In one strike on Balakliya in Eastern Ukraine, drones dropping thermite grenades reportedly caused a billion dollars’ worth of damage and destroyed thousands of tons of munitions. This might now be seen as a strategic move to deprive Ukraine of much-needed artillery ammunition in the subsequent invasion.
A Russian tank explodes after being hit by an FPV, as the drone strike detonates stored ammunition.
Ukraine MoDBut bringing the detonator also operates at the most tactical of scales. When an FPV destroys a tank – sometimes in a dramatic fireball – most of the damage is not caused by the drone warhead but by the detonation of stored fuel and ammunition.
This is more obvious when artillery is targeted, such as a recent strike on a Russian truck-mounted rocket launcher supplied by North Korea. The launcher is in the lowered position for transport, and when the FPV hits it sets off rockets, with one firing through the cab before everything blows up. An empty truck would be much less vulnerable.
Equally when Ukrainian FPVs struck parked Russian bombers in Operation Spiderweb, the small explosive charges on the drones were merely detonators. If the aircraft had no fuel or munitions they might have escaped minor damage. But fueled up and carrying cruise missiles, the aircraft were easily set ablaze and destroyed.
This capability will become more important as we see more long-range attacks, including those by FPV carriers above to deliver small drones to targets hundreds of miles away. Under the right circumstances, a small drone can destroy even the most robust concrete structure simply by bringing the detonator.