Ukraine is developing a “long” version of its ground-launched Neptune cruise missile—one of its main weapons for striking Russian forces deep behind the front line of Russia’s 22-month wider war on Ukraine.
The coming of the Long Neptune is good news for advocates of a free Ukraine. Especially considering the possible throttling of U.S. support for the Ukrainian war effort. Throttling that’s being advanced by a minority of pro-Russian Republicans in the U.S. Congress.
The news broke on Monday in ArmyInform’s interview with Lt. Gen. Ivan Gavrylyuk, Ukraine’s deputy minister of defense. “Currently, work is underway to create the so-called ‘Long Neptune,’” Gavrylyuk said. “This is a new modification of the missile for the Neptune complex.”
It’s obvious what’s happening—and it’s obvious because it’s happened before, when other countries enhanced their cruise missiles by making them longer. In extending the 17-foot Neptune and filling the extra space with additional fuel for the missile’s turbofan engine, Ukraine could add a lot to its approximately 200-mile range.
Consider the Harpoon, the U.S. Navy’s classic anti-ship cruise missile, which also has land-attack modes. Ukraine operates a small number of donated Harpoons alongside its locally-produced Neptunes and other deep-strike munitions including air-launched Storm Shadow and SCALP-EG cruise missiles and ground-launched S-200 and Tochka ballistic missiles.
The basic surface-launched Harpoon ranges no farther than 75 miles. In 1991, arms-maker McDonnell Douglas—now Boeing—offered a new Block 1D model of the Harpoon that added two feet to the 13-foot missile. “A structural modification provides additional volume for fuel, thus doubling range,” McDonnell stated in a sales brochure.
The U.S. Navy never showed much interest in the Harpoon Block 1D at a time when a major war with Russia seemed like a distant prospect. But the new missile at least proved, again, how to extend the range of a cruise missile. Make it longer, add more fuel.
The trick is to rebalance the missile after the addition. In the case of the Harpoon 1D, that meant repositioning the wings, which the Americans “moved forward to maintain maneuverability and flying characteristics.”
The Neptune might undergo similar changes. Those tweaks, plus any related modifications to the missile’s truck-mounted launcher, should be straightforward. Luch, the Ukrainian design bureau responsible for the Neptune, for months has been teasing enhancements to the Neptune that would extend the missile’s range to 225 miles.
The longer body might not be the first modification to Neptune. The earliest models of the missile, which is a derivative of the Soviet-vintage Kh-35, had radar seekers that limited their role to anti-ship strikes. Indeed, the Neptune’s first victims were Russian warships, including the missile-cruiser Moskva, holed and sunk in the western Black Sea back in April 2022.
Many anti-ship cruise missiles also have ground-attack modes, but these same missiles often feature GPS-aided navigation.
The reason is simple. A radar seeker generally is enough for striking ships, as a ship reflects a clear radar signature relative to the flat water around it. Ground targets, by contrast, are surrounded by the clutter of buildings, trees and uneven terrain. But juice a radar-guided missile with GPS, and you might get enough discrimination to steer the munition through the clutter to its target.
Luch in its wisdom fitted the Neptune with GPS from the start. But the design bureau made additional tweaks to the missile’s seeker to optimize its land-attack mode, a Ukrainian official told The War Zone in April. “We are pretty close.”
The official wasn’t lying. Just four months after The War Zone interview, the Ukrainians began firing Neptunes at Russian air-defenses on land in occupied Crimea.
A Long Neptune that also has the improved seeker might be able to range more than 200 miles. Potentially a lot more. That could put all of occupied Crimea plus adjacent Russian territories within range of Ukrainian batteries firing missiles from well behind the front line.
The Long Neptune is just one of several domestic deep-strike munitions. They also include newly-produced copies of the classic Tochka ballistic missile. It’s not for no reason Kyiv is prioritizing the development of indigenous deep-strike missiles. Supplies of foreign deep-strike missiles are thin—and could get thinner.
The United States shocked observers this fall by supplying Ukraine with a batch of around 20 ground-launched M39 ballistic missiles—and then surprised them again by apparently not sending additional batches of the lethal munitions.
Money is one problem. U.S. president Joe Biden has warned that the Congressional funding his administration relies on for military support to Ukraine will run out this year.
Biden has proposed an additional $67 billion in funding, but a far-right fringe in the slim Republican majority in the Congress’s lower house—as well as that majority’s extremist leader, Rep. Mike Johnson—have made funding for Ukraine contingent on profound changes to the American system for offering asylum to refugees.
In essence, Republicans want to strip away the government’s power to offer asylum to populations fleeing natural disasters and other crises. Democrats in Congress have rejected this demand. Unless one side caves—or both reach a compromise—American money for Ukraine could run out soon.
That might mean no more U.S.-made long-range missiles for Ukraine’s deep-strike campaign. In that case, the Ukrainians would rely more on domestic missiles. Including the Long Neptune.