The ballistic missiles that struck last week, targeting both a school in Ramat Efal and a playground in Jaffa, appear to have unsettled not only senior defense officials but also the general public that has grown accustomed to believing in the near-impenetrability of Israel’s defense systems.
Currently, much remains unclear, but it would be better to consider a worst-case scenario – one that assumes our adversaries have achieved a significant leap in their missile capabilities – rather than attributing these incidents to a mere “technical glitch” on our part.
So, what is this leap in capability? Historically, missiles launched from Yemen (or Iran) followed a predictable ballistic trajectory. After the rocket engine burned out, their course resembled that of a stone hurled into the air: a simple, predictable arc governed by gravity.
By calculating a few key parameters, defense systems could accurately predict the missile’s path and deploy interceptors to neutralize it at specific points along its route.
Now, however, it seems our enemies are attempting to complicate this process by altering the trajectory of the missile mid-flight, making it harder to predict and therefore harder to intercept. How might they achieve this?
One method involves adding small fins to the missile, which can be adjusted to create aerodynamic forces that steer the missile away from a purely ballistic path.
This is somewhat analogous to how a shuttlecock in badminton doesn’t fly like a regular ball; instead, it slows down and changes direction. These fins can be angled to exert control over the missile’s movement, albeit with limitations.
For instance, fins are ineffective in space and are prone to melting due to intense heat during reentry into the atmosphere. However, for engineers on the opposing side, these drawbacks may not matter. As long as they’re not aiming for pinpoint accuracy, they can accept the destruction of these fins partway through the missile’s journey.
Another approach involves equipping the missile with small rocket thrusters positioned perpendicular to its main axis. These thrusters, by expelling gas at high speed, can nudge the missile off its ballistic course and into a predetermined path.
This principle, which is also employed in spacecraft propulsion, is akin to the erratic motion of an inflated balloon released into the air. Such maneuvering systems make the missile’s flight path less predictable.
These innovations and additions, however, come at a cost. To make room for guidance systems, the payload – typically the explosive warhead – must be reduced. This trade-off was evident in the Ramat Efal incident, where initial assessments suggested the missile had fragmented before impact.
In reality, it likely carried less explosive material to accommodate its guidance mechanisms.
Should we lose hope?
So, what can be done? Should we despair? Absolutely not. Israel’s defense systems are among the most advanced in the world and are capable of handling maneuvering targets.
From detection and tracking to interception, they have already proven effective in dealing with similar challenges elsewhere.
Of course, this is no simple task. The high speeds of both the interceptor and the missile require near-perfect precision for a successful interception. Yet, these challenges are familiar territory for the engineers in Israel’s defense industries.
We must trust that lessons have been learned and improvements implemented swiftly to prevent a future scenario where a ballistic missile strikes a densely populated area.
The writer is the head of the School of Mechanical Engineering at Afeka – The Academic College of Engineering in Tel Aviv.