Rahul Mehta wrote:One reason why "so much was done" was to cover up the fact that "nothing was done"
Allow me to explain.
1. Blackbox etc transmit the signal which can give location of the chopper within minutes. So location was known minute the chopper crashed.
2. The location was kept hidden from public, and a small team was sent to check that accident was successful, and if not, ensure the success of the accident.
3. And meanwhile, to show that "hectic" efforts are being made to locate YSR, Sukhoi plane was called, and 100s of commandos were dispatched and so forth.
Conspiracy theories are a dime a dozen. They come crawling out like unwanted bed bugs
What sort of "blackbox" are you referring to, that """ which can give location of the chopper within minutes """?
A bit of restraint and understanding of facts is called for.
The helo VT-APG, carried a dual frequency Emergency locater transmitter (121.5 vhf distress / 243.0 uhf distress)
There is a DGCA circular to say that 121.5 MHz would not be monitored from Feb 2009 onwards. So that left the helo with only 243.0Mhz.
So if there was indeed an automatic ELT transmission from the helo on impact or otherwise, it would have automatically been picked up on the satellites and there after this transmission would have triggered an international response with ICAO and others getting involved.
A NOTAM would have very quickly been issued and international and other flights transiting overhead the vicinity would have been alerted to keep a special watch for any distress signals. Many international flights overflying India on their way to and from eastern destinations would have easily been able to pickup such a signal and there would have been an immediate response and activation of emergency services. Distress frequencies are often automatically and continuously guarded on aircraft radio sets. The alarm from such a distress signal pickup cannot be ignored and will invariably set off a chain reaction that starts when the pilot picking up such a signal reports it to the ATC.
243.0 MHz is a line of sight transmission and the line of sight from 35-45,000 ft is some hundreds of kilometers. Per your conspiracy theory, pilots of many nationalities randomly flying overhead would have to be paid off.
You don't seem to understand or appreciate the immediate response that results when a distress signal is monitored.
Pilots respond instantaneously and instinctively to the distress of another pilot. The airwaves would have been filled with this news and the resulting chatter between pilots warning other pilots to watch for and monitor the distress would have been enormous.
Since the emergency services did not respond to a satellite alert, ergo, there was no transmission from VT-APG, impact or otherwise.
406 MHz transmitter was not carried or fitted on this helohttp://126.96.36.199/search?q=cache:LEZ ... clnk&gl=in
3. Indian Ground System
A typical ground system consists of an antenna to receive the signals from the satellites, a RF (Radio Frequency) system to strip the signals from the downlink frequency (1544.5 MHz), computers to determine locations, and collate & distribute satellite derived information to the appropriate agencies. The antenna, RF system and processing computers are generally grouped together to form a LUT. The computers, which collate and distribute location information to Rescue Coordination Centres (RCCs) are generally grouped together to form a Mission Control Centre (MCC). Fig 2 represents the Indian LUT - MCC block diagram.
Two LEOLUTs (Low Earth Orbiting LUTs) were set up by ISRO, one each at Bangalore (1989) and Lucknow (1990). The Indian Mission Control Centre (INMCC), responsible for coordination with the rescue coordination centers, and other international MCCs is co-located with the Bangalore LUT. The Indian GEOSAR (Geo-stationary Earth Orbiting SAR) system with one GEOLUT at Bangalore and Indian satellite INSAT-2A became operational in 1992. The INMCC is connected with 4 RCCs of the Airports Authority of India (AAI) situated at 4 metro airports (Chennai, Mumbai, Delhi and Kolkata) and Maritime Rescue Coordination Centres (MRCCs) of Coast Guard situated at Chennai Mumbai. The INMCC operates 24h a day, 7 days a week and relays the distress alerts to RCCs and MRCCs using Aeronautical Fixed Telecommunication Network (AFTN) communication system provided by the Airport Authority of India (AAI). INMCC also implemented Internet based data communication system using “FTP” and “Email”, which is already operational with external MCCs.
As the satellites orbits the earth, they receive any signal being transmitted in the emergency bands by distress beacons operating on any (or all three) of the distress frequency bands 121.5 MHz, 243 MHz and 406 MHz. Once received, the signals are immediately retransmitted back to earth in a process referred to as the "bent pipe" (repeater) mode. In this mode, the satellite must be in the visibility of a LUT for the signals to be received and processed, or else the information is essentially lost. Because the 406 MHz signals contain identifying data, they can easily be stored and then later processed. By tagging each unique 406 MHz signal with the time, the ground based computers can determine locations anywhere in the world. Hence, the storing and subsequent transmission of 406 MHz data is referred to as the "global" mode.
The location of beacons is determined by Doppler principle using the relative motion between the satellite and the beacon. With the precise measurement of Doppler and the knowledge of satellite orbit, position of distress signal can be estimated. The accuracy of Doppler location is within 20km for 121.5/243 MHz beacons and within 5 km for 406 MHz beacons. The new generation 406 MHz beacons are capable of providing GPS location within 100 m accuracy.
2.1 User Services
INMCC, ISO 9001/2000 certified, provides operational support through an organised system as per international Cospas-Sarsat standard. The system is designed to operate automatically with minimum operator interaction - manned only during office working hours (09:00 – 17:30 hrs, local time), Monday through Saturday. The availability of system is maintained higher than Cospas-Sarsat specifications (LUTs > 95%, INMCC > 99% in a year). INMCC at Bangalore provides following services to user community:
Satellite based distress-alerting services to marine, air and land based users in the sub-continent, 24 hours a day, 7 days a week and 365 days in a year.
Maintenance and operation of national beacon registration database to provide information on vessel, aircraft or person in distress to national and international SAR agencies
Necessary training to rescue agencies and organize system awareness and promotional activities for various user communities/segments
Support and planning of beacon and system test exercises as per requirements
Allocation of serial numbers, maintenance of an inventory, and necessary support and guidance to users for beacon coding