ALH Dhruv is cleared for operations at higher altitudes as well, but that's just what it means: flying at those altitudes. In Siachen, you need to hover and land and offload supplies. And these are at altitudes above 22,000 feet. The ALH Dhruv even with the Shakti engine cannot lift more than a few dozen kilos at that altitude in Hover OGE (Out of Ground Effect. Note: helipads in the Siachen often are nothing more that table top pads. In this case the helicopter needs to be able to hover OGE entirely without expected IGE assistance). This is because of its heavier design weight.soutikghosh wrote:Although a bit heavier, why can't ALH Dhruv fullfill the role of Light Utility Helicopter after all it is fully qualified for hot and high operations of Siachen.
By comparison, the Cheetah lefts up to around seventy odd kilos after adding all other weights at the same altitude for much lesser operational cost. Now the LOH is required to lift at least around 200 Kg of payload at the same altitude if it is to provide any additional improvement in lifting capacity over the Cheetah. This payload requirement number is from the BR pages itself, though I don't have the link right now. Nevertheless, the only way the helicopter in the LOH category can lift such a load is if its power remained the same but the weights was reduced. In that case the HAL designed LOH with the same powerplant design but much smaller fuselage is the logical choice, but the Dhruv in itself is not.
-Vivek