Denmark has announced that 80 Leopard 1A5s will be delivered to Ukraine by June 1st. Training on the tanks had been ongoing in Germany, and the training is expected to be complete in time for a June 1st delivery. Leopard 1A5s may go into action as soon as the first week of June.
The Leopard 1 is a venerable tank, which is a nice way to say it is old. First entering service in 1965, it is a rough contemporary with the T-64.
Much like T-64 and T-72 tanks that remain in service on both sides of the Russo-Ukrainian War today, the Leopard 1 went through a series of modernization programs up to 1980, when the 1A5 represented the most upgraded version of the Leopard 1,
The most significant upgrade on the Leopard 1A5 is on the offensive side. Its 105mm main gun is considered underpowered for a modern main battle tank (MBT), but it has been fitted with a fully modern and integrated digital Fire Control System (FCS).
The modern FCS allows the Leopard 1A5 to hit targets accurately up to the visual horizon (6000m), and the upgraded main gun can fire APFSDS kinetic penetrator rounds that give it enough punch to destroy older Russian MBTs and most any Russian Infantry fighting vehicle (IFV) or Armored Personnel Carrier (APC).
On the other hand, the 105mm gun will struggle to penetrate the frontal armor of any more modern Russian MBT like the T-80s or the T-90, although it should be capable of doing significant damage to more lightly armored tanks.
However, this limitation pales compared to the Leopard 1A5’s greatest weakness: its armor. The Leopard 1 weighs in at just 42 tons, compared to the 70-ton Leopard 2. The Leopard 1’s frontal armor is just 70mm thick, less than 1/10th the thickness of the Leopard 2’s frontal armor. Its armor is so weak that most military analysts believe that the Leopard 1 is unsuitable for combined arms operations at the spearhead of an assault.
You might ask, why should we be excited about the arrival of 80 such tanks?
The Leopard 1 is ideal for urban warfare and mopping up Russian strong points bypassed by spearhead units.
Behind the Spearhead
When you look at the 2022 Kharkiv Counteroffensive in its early stages, at the time that the Ukrainian Army punched a hole through the Russian defenses, what you see is textbook armored warfare. As much as possible, the Ukrainian spearhead handed off attacking Russian strongpoints in towns and cities to slower infantry-based units coming up behind them.
This freed up the spearhead assault units to keep pressing forwards at a rapid pace, exploiting the breakthrough and racing through rearward Russian defenses before the Russian army could react effectively.
However, to advance rapidly, spearhead units will need to bypass heavily entrenched Russian units in towns, villages, or trenchworks. These units can be left for later, but they cannot be ignored.
A good example of what happens if you DO ignore such units is what happened to Russia during their early push toward Kyiv from Feb. to March 2022. Russian units pressed straight down main highways, not bothering to capture and secure Ukrainian towns adjacent to the Russian routes of supply.
Ukrainian partisans and special forces commandos began using those towns as bases to launch disruptive commando attacks on Russian logistics.
Spearhead units cannot waste time capturing non-critical towns and other strong points in the Russian defense, but leaving them uncaptured longer term is folly as well.
You need a second wave of troops advancing behind the “spearhead” assault units whose role is to take on these Russian strong points.
These types of operations are sometimes called “mop-up operations” but this undersells their difficulty and importance.
While withdrawing Russian units likely will take the best-armored vehicles, most especially any modern MBTs with them as a priority, the bypassed strongpoints often will have been bypassed specifically because they are formidable defenses of themselves.
Sometimes they can simply be surrounded and forced to surrender, but in other locations assaulting them may be the only timely option, as roads or rail lines running through the locale may be needed ASAP for logistical reasons.
The most critical of such points will often be towns or small cities defended primarily by Russian infantry supported by IFVs or older model second-line tanks.
It is in these operations that Leopard 1s will be ideal.
Leopard 1 in Urban Combat
The first and biggest reason the Leopard 1 is well-suited for this type of second-wave attack role is that its shortcomings are less likely to matter—or will be at no more of a disadvantage than most newer tanks.
For example, the Leopard 2A4 has relatively weak flank and rear armor, and thus its weaknesses could be exploited in closer-range urban combat. In a previous diary, I discussed in detail how this shortcoming was exploited in Syria against the Turkish Army. I also described in a prior diary how the PT-91 Polish tank, while a fine tank, also shared similar concerns.
Ukraine has a sharply limited supply of tanks designed for close-range urban combat, like the Leopard 2A6 or Challenger 2. These two tanks were designed with urban combat in mind, and feature powerful flank armor that keeps them safe from most close-range ambushes by anti-tank guided missile (ATGM) armed infantry.
That leaves a broad range of tanks with similar though varying levels of vulnerability to infantry ambush in urban environments. Pushing high-value and difficult-to-replace Leopard 2A4 or even PT-91 tanks into urban combat seems like a waste of their abilities.
The Leopard 1A5 is ideal, in part because its utility in other roles is limited; thus its vulnerabilities are not so pronounced compared to the alternatives.
Furthermore, though the Leopard 1A5’s protection is weak for an MBT, it is quite strong compared to many infantry support vehicles available to 2nd line units. For example, elements of the Spartan Brigade (one of the new Storm Brigades raised by Ukraine) were dispatched to fight in Bakhmut, and they were given BTR-4s.
The BTR-4’s armor is thick enough to protect against shrapnel from artillery, or heavy machine gun rounds. It is reasonably mobile and can move soldiers quickly and cheaply. It is clearly better than nothing. But it provides next to no protection against even the weakest IFV autocannons, and virtually any anti-armor weapon (even armor-piercing heavy machine gun bullets) will pose a grave threat.
By comparison, a crew in a Leopard 1A5 rolling through a city would be dramatically better protected, and the 105mm main gun will provide overwhelming firepower.
But one of the biggest advantages offered by a Leopard 1 in urban combat is in a unique tank round that only tanks with rifled barrels can fire: the HEP (High Explosive Plastic) round in US terminology, or the HESH (High Explosive Squash Head) round in the British Army.
Developed by the British Army in the 1940s, it was designed as a bunker-busting anti-fortification round but was found to also be surprisingly effective against armored targets of the 1950s and early 1960s. It was used by many Commonwealth military forces throughout the Cold War and beyond.
Its design requires the shell to be rotating on impact, and thus can only be used by rifled barrel tank guns. For the Ukrainian Army, only the Challenger 2 and the Leopard 1 have a rifled barrel, as most other modern tanks utilize a smoothbore barrel.
The shell contains a large amount of plastic explosive that “squashes” on impact. Upon explosion, the round transmits shockwaves to the inside of the structure, causing the interior to fragment and be blasted at high speeds. This effectively creates a wave of shrapnel within the attacked structure.
It has proven devastatingly effective in urban combat, used by the Canadian Army against Afghan insurgents in 2006.
Furthermore, the Leopard 1A5 has numerous customizable equipment attachment points. For example, in rubble-strewn streets in an urban combat environment, having a bulldozer blade attachment can make it easier for the Leopard 1 itself to move about, but it can also clear a path for wheeled Armored Personnel Carriers to follow.
Given that Ukraine will need its best sapper units (combat engineering units) to accompany the spearhead units, any engineering capabilities the Leopard 1 can contribute may be disproportionately important for the 2nd line units tasked with crushing Russian infantry in urban contexts.
Conclusion
Would 80 Leopard 2s be more welcome than 80 Leopard 1s? For obvious reasons, yes.
However, simply because the Leopard 1 is an old tank no longer suited to lead the assault doesn’t mean it won’t have an important role to play during the Summer Offensive.
Rapidly clearing out Russian strong points to keep the flow of supplies moving and secure is just as mission-critical as the spearhead’s ability to pierce through Russian defenses.
The Leopard 1A5 will be a cost-effective and deadly contribution to Ukrainian units tasked with following up the advances of the spearhead units.