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The war in Ukraine has exposed a series of military vulnerabilities in the Russian armed forces, defence analysts say.
Ukraine's army is not only performing better than expected, it has also dogged the Russian invasion with a stockpile of anti-tank and anti-aircraft weapons.
Most worrying for Moscow’s generals is that Ukraine defences have the ability to take out advanced tanks, jets and attack helicopters while Russian forces have lacked co-ordination.
“The initial handling has been quite surprising and at a tactical level we thought the Russians were better than this,” said Sam Cranny-Evans, a Russia military expert at the Rusi think tank. “We were expecting it to be a lot more co-ordinated than it has been, especially in combined arms operations. This is probably down to a combination of five or six things going badly wrong.”
However, the Russians might be undertaking what the military calls “reconnaissance in force”, with smaller units probing defences before heavier units arrive.
This might explain why images in Kharkiv show soft-skinned Russian TIGR vehicles – similar to the American Humvees – crippled by gunfire. Similarly, a number of eight-wheeled BDRM armoured vehicles, used by paratroopers and special forces, have been knocked out.
This perhaps accounts for the Ukrainian Defence Ministry's claim that 5,300 Russian servicemen have already been killed and 191 tanks, 816 armoured vehicles, 29 helicopters and 29 aircraft destroyed. Even if these figures are overestimated, they suggest that stiff resistance has hampered the Russian advance severely.
The assault has been a disjointed nature. The Russians were supposed to have highly competent and well-organised Battalion Tactical Groups that combined tanks, armoured infantry and artillery. Due to Ukrainian ambushes, poor planning or luck, these groups have become separated from the main battle tanks and artillery, and unable to support infantry.
There are reports of units running out of petrol with poor planning on fuel estimates.
However, it is far too early to say that the Russians have been defeated militarily. It may be that within a few days the heavy armour and artillery will arrive along with close air support to allow the infantry to take major cities such as Kiev and Kharkiv.
Many units are new to operations and the experience of combat will probably turn them into battle-hardened fighters.
But the Russian military is taking losses. Several of the new Ka-52 Alligator attack helicopters have been shot down, with the fragmentation damage suggesting they were hit by Stinger missiles.
“The Ka-52 is one of Russia’s top-end military helicopters,” said Dr Richard Connelly, a Russia expert at the University of Birmingham. “They are using and losing them in Ukraine and really haven’t got vast quantities of them to lose.” Slightly more than 100 of the Ka-52s are in service.
Baltic states have supplied the Ukrainians with the short-range but highly effective Stingers but Ukraine might also have assembled a stockpile covertly, provided by others including the US.
Similarly, before the war began it was suggested that Russia's T-90 tank would prove highly effective, yet it too has been vulnerable to the modern NLAW (New Light Anti Tank Weapon) and Javelin missiles supplied by Britain.
Ukraine has a far more advanced local defence industry than many realised, with the ability to produce its own tanks, aircraft and missiles.
The Skif guided anti-tank missile, developed by Ukraine’s Luch Design Bureau, uses a laser beam for target guidance either against vehicles or hovering helicopters. It is widely distributed, either fired from a tripod or mounted on vehicles.
The combination has clearly blocked Russian President Vladimir Putin’s hopes of a swift victory. There are also concerns that Russia’s tactics will follow those developed in Chechnya when its forces initially received a bloody nose but then flattened its capital city of Grozny.
“This mixture of overconfidence and under competence that we're seeing from the Russians at the moment feels exactly like when they moved on Grozny ... in December 1994, when they made exactly the same mistakes but then brought in a lot more resources and were much more ruthless,” said Keir Giles, a Russia specialist at Chatham House.
Boris Johnson told his Cabinet on Monday that it was becoming clearer by the day “that Putin had made a colossal mistake” in believing that “the guns of his tanks would be garlanded with roses when instead Ukrainian people had put up a fierce resistance in defence of their homeland”.
The British prime minister said the latest intelligence suggested that these “heroic efforts of the Ukrainian military” were inflicting significant casualties on Russian troops.