Unmanned Combat Air Vehicles, or UCAVs, are increasingly an important capability available to military commanders and, as they become more capable, they will be able to replace cruise missiles in many of their traditional roles. This article looks at some of the possible trends for both UCAVs and cruise missiles in order to predict if cruise missiles will be able to survive the competition.
Cruise missiles and UCAVs have a long heritage, both having predecessors that appeared during World War Two. The German V1 was an early example of a cruise missile and the American TDR-1 was an unmanned, remotely piloted aircraft
which was able to drop 2000lb bombs and torpedoes.
UCAVs do not have a long record of operational use. There were limited experiments during the 1970s, but the first operational ‘kill’ for a UCAV had to wait until November 2002, when an armed Predator UAV targeted a convoy of vehicles in Yemen.
A UAV is defined as ‘an aviation system that has as its centrepiece an uninhabited reusable aircraft that sustains flight using onboard propulsion and aerodynamic lift’.2 A cruise missile is defined as a ‘guided missile, the major proportion of whose flight path to its target is conducted at approximately constant velocity; depends on the dynamic reaction of air for lift and upon propulsive forces to balance drag’.3 The only significant difference between the two definitions is the use of the word ‘reusable’ in defining a UAV.
Likely Future Advances – Cruise Missiles
Tomahawk and Storm Shadow both have similar planned enhancements ahead. These will provide real-time control over the targeting of the missile while it is in flight. Initially, this would consist of an ability to transmit images of the target to a manned unit and provide a check that the missile is attacking the correct target
Another area which is being researched is to deploy cruise missiles that are significantly faster than the current generation. This would improve reaction time by providing an ability to hit targets far quicker than is currently possible, enabling more fleeting targets to be engaged, thus enhancing the survivability of the system, despite making the missile more detectable.
The unit cost of a cruise missile can be extremely high, particularly when compared to a single precision weapon, such as the GPS guided JDAM. This is especially true of Storm Shadow, due to its shorter production runs and more complex design. There will be a drive to reduce the unit costs of cruise missiles whilst maintaining as much of the capability as possible.
Likely Future Advances – UCAVs
The continuing proliferation of advanced SAM systems to a wide range of countries will force the adoption of widespread LO (Low Observable) technology in UCAVs and manned aircraft alike. The cost advantage of a UCAV compared to a manned platform will not be maintained if the UCAV is much less survivable. Whilst survivability could be assured through use of extremely high speed, this will degrade the targeting imagery and accuracy.
As in common with many other modern airframes, a future UCAV with a stealthy design is likely to be aerodynamically unstable. This will raise the complexity of the platform considerably, particularly when compared with the simple design of the Reaper. The survivability will raise the airframe unit cost, through the expense of the materials and the design work required for LO and through the advanced avionics needed to ensure that the system is safe and effective.
For a future UCAV to be effective, it will require long endurance so it is either able to loiter over its target region, or have an extremely long transit to the target.It is projected that UCAVs could reach a point of complete autonomy, only requiring human input for weapon release authorization.
In order for the future UCAV to be cost effective in the strategic strike role compared to cruise missiles, its payload will have to be fairly low-cost. However, these low-cost alternatives exist in the form of JDAMs and LGBs, both of which offer reasonably high levels of accuracy when dropped by a stable, local platform.
Analysis of Future Capability
Many of the problems and opportunities presented by current cruise missiles and UCAVs will still be present in their future incarnations. The response from a future UCAV near to the target area will still be faster than that from a cruise missile launched from an off-shore naval platform. However, a future UCAV with an increased range and an ability to operate outside national airspace (above 60,000ft) will provide an ability to strike a target anywhere globally within hours. Cruise missiles will still require a launch platform to be inside missile range of the target. However, as currently, cruise missiles will be available on many platforms (although most are likely to continue to be naval), which increases the chance that at any given moment a target will be within a relatively short flight time of a missile.
As both systems will continue to perform roles without risking a manned aircraft near enemy air defenses, the risk to human personnel will therefore remain low. However, the risk must also be measured in terms of political and monetary cost.
The high unit cost for the future UCAV will be offset by cheap payloads and by being extremely reusable. However, the cost benefits will be completely eroded with even a small number of platform losses. As cruise missiles are one-shot devices, the potential financial risk will always be constant.
The future of cruise missiles and UCAVs is a competitive one. UCAVs will develop capabilities that enable them to perform cruise missile roles at a fraction of the cost. The political dimension of these weapons can also not be ignored. Whilst both can operate without any host-nation support, the long transit time for a future UCAV to arrive at the target area from a friendly airbase degrades its ability to loiter over and reconnoiter the target. A cruise missile on the other hand can be forward deployed on a politically deniable platform nearer to the target area, which will ensure prompt responsiveness. In the case of a submarine-launched missile, the launch platform can remain entirely covert.
The cost benefits of future UCAVs hinge around their ability to perform strike missions safely with cheap weaponry. However, the proliferation of extremely sophisticated air defence systems is likely to continue unabated and it will be possible for an enemy to create a defence network that not even a stealthy, heavily armed UCAV can penetrate.
Against strong air defence systems, cruise missiles will be able to degrade the defences quickly to the extent that cheaper UCAVs can operate.Whilst future UCAVs will take over many of the cruise missiles’ traditional missions, future cruise missiles will be able to complement them. Their responsiveness, survivability and ability to operate from a wide range of different platforms ensure that in many scenarios they will continue to be as relevant in future conflicts as they are today.