RFI for Trajectory Correctable Munitions, Terminally Guided Munitions
DG Artillery under the Integrated Headquarters of Ministry of Defence (Army) has released 3 RFIs related to ammunition. Two of them are in relation to smart ammunition - Trajectory Correctible Ammunition (TCM) and Terminally Guided Munition (TGM).
"Less than 1% of Indian munition is Precision Guided". So it good to see that the Army is seriously considering this purchase. The following is a tech primer. 8ak's detailed report "Challenges in India's Artillery Modernisation Program" will be released on Jun 14 which will be tech primer, operating guide and summary of artillery tenders, all in one.
In conventional munition, a fuze is attached to the shell and acts purely as a detonation device which controls whether the munition bursts after a set time, after penetrating the target or at a particular distance from it. In case of such conventional ammunition, the probability of hitting the target is directly proportional to the distance from the gun. There are currently two main ways to make munitions more accurate.
a) Provide navigational information to the munition. Using GPS/INS information, the shell can correct its line and range for improved accuracy. This is trajectory correctible munition (TCM) like BAE Bofors Bonus now under development.
b) Since the target could have moved by the time the co-ordinates reach the gunner, the second method is that instead of getting locational information, the sensors instead get information from the target. In case of the Copperhead or Russian Krasnopol, which are laser guided, the target has to be highlighted with a laser designator, possibly by a forward observer. Since the munition is guided by emissions from or bouncing off the target, it is called Terminally Guided Munition (TGM).
When there is no one to illuminate/highlight the target, sensors IR/MMW can be fitted in to the fuze/shell so that it can identify the target itself. In case of the now discontinued Sadarm system this was done via a IR/MMW sensor fuzed submunitions over the target. This top-attack munition could take out a tank.
But these methods are expensive. Each Excalibur shell in use by the American's in Afghanistan is $80,000 - 100,000. Also, most countries have huge ammunition stockpiles that are not refreshed unless used in war or discarded due to obsolescence. Hence, there are precision guided kits that are basically a replacement for the fuze. These mostly have GPS/INS capability and cost less than $3,000 and offer similar CEPs as that of TCMs.
Use of precision weapons reduces the amount of ammunition required to achieve the mission and hence huge reduction in inventory and related logistics. So it is easy to think that this could be the end of dumb ammunition. But it is not because at short ranges dumb munitions may be just as effective, they are much cheaper and can be used in combination with smart ammunition. For eg a commander may choose to first use a few precision rounds and then follow up with 'steel rain' to create psychological fear in the enemy and destroy other lower value targets/infrastructure. Hence, IHQ (Army) has simultaneously issued a RFI for a 120mm mortar system. US company ATK also offers precision capability in mortars.
The tenders can be found on tenders.gov.in. Key people who are expected to respond are BAE Systems, Raytheon, Israel's IAI and Russia's KBP Instrument Design Bureau.