On 10 October, in a parade celebrating the 75th anniversary of the founding of the ruling Workers' Party, North Korea revealed what we may presumably call the Hwasong-16 ICBM. Missile defence experts have been speculating about the capabilities of the new missile, and most significantly its size.
Speculations ranged from it being designed to carry multiple warheads and decoys to ensure the penetrability of America’s missile defences, to being armed with multiple independently-targetable reentry vehicles (MIRVs).
Michael Elleman, a Senior Fellow for Missile Defence at the International Institute for Strategic Studies whose work focuses on assessing and countering missile threats, presented his analysis suggesting that "while the new missile has the thrust to deliver a heavy payload over intercontinental distances, its mobility is going to be severely limited by its tremendous size and weight."
In his analysis, Elleman suggests that the heavyweight of the missile makes it dangerous to transfer it when it is fuelled, therefore requiring to fuel it at the launch site after it has been erected.
Elleman's suggestion indicates that in the case of a pre-launch attack, there would be technically no time to prepare the missile, making it vulnerable to such sort of an attack.
The theory of it being a "fake missile" was included in Elleman's analysis, based on the fact that "North Korea has a history of introducing “fake” missiles during celebratory parades."
As for the size of the Hwasong-16, all estimates of the missile's diameter relied on the photographs taken during the parade. Those estimates naturally varied because no design documents or technical manuals are available.
Values developed by specialists "indicate a Hwasong-16 diameter ranging between 2.4 and 2.5 meters, and a length of roughly 24 to 25 meters." writes Elleman. "These data can be used to estimate the missile’s lift-off mass by assuming the Hwasong-16 has an average density consistent with Soviet and American liquid-fuel missile designs from the 1960s and 1970s [...] f its diameter falls within the 2.4 to 2.5-m estimate, the Hwasong-16’s total mass, when fully fueled, is somewhere between 80,000 and 110,000 kg." the expert adds.
Concluding his analysis, Elleman syas that North Korea cannot guarantee that its ICBMs will be capable of striking the US mainland, and that "the development of the Hwasong-16 is a near-term solution to the perceived need for a mobile, multiple-warhead ICBM." Furthermore, an enterprise to develop a longer-term development of solid-fuel technologies and a solid ICBM would take four to five years at least.