Mysterious silence of AP Chief Minister’s copter

Aviation experts are intrigued on one issue concerning the disappearance of the helicopter of Andhra Pradesh Chief Minister Y Rajasekhara Reddy: Why is there no signal coming from the BEL 430 chopper?
Helicopter experts point out that the BEL chopper is equipped with an Emergency Location Transmitter (ELT) that can send out signals for 48 to 72 hours. The ELT gets automatically activated if the chopper crashes. But if it has been caught in a difficult weather or terrain, the pilot can manually activate the ELT.
In the case of YSR's helicopter, neither of this has happened. This is a mystery. Experts say there could be two reasons: The ELT probably is not functioning (which, if true, is a major lapse) or there was a serious mechanical problem that rendered the ELT useless (which is a remote possibility).
If the signals were emitted, it could have been captured by the search and rescue satellite operated by ISRO. The satellites of ISRO have a transponder only for this purpose and it is use extensively by the Air Force in case of a missing plane - either of India or other countries.
Since this signal did not come from YSR's chopper, the Air Force decided to press in the Sukhoi-30 fighters that have very sensitive radars and capabilities to reconstruct a thermal map of a wide area. The Sukhois can catch any unusual event in difficult terrain.
In 2005, it was a Sukhoi that caught an unusual activity in the deep forest area of Belgaum where an Indian Navy plane had gone missing for four days. Based on the Sukhoi's inputs, troops were able to locate the aircraft after five days and found a survivor who was still strapped to his seat.
The government has also pressed in the aircraft of National Remote Sensing organisation (NRSA ) that can fly at very low altitude and has good night vision.
The problem, according to experts, is that in case of an emergency landing or crash of a helicopter in dense forest, the `disturbance' in the area will be hardly 200-500 metres. Such a small disturbance is hard to locate by overhead flying planes. It all depends on how big a `footprint' the aircraft leaves behind when it goes down, said an expert.
The only hope is to physically look out for the helicopter through dense combing operations. That is why the Army has pressed in its elite troops that have what is called `deep instincts' to locate and rescue personnel.
Reports also indicate that the pilot may have deviated from the approved flight path in order to avoid rough weather conditions. This has made the search operations difficult. If the pilot had stuck to the flight path, it would have been easy to pin-point a rough area where it went down by calculating the flight duration.