The recent disappearance of Malaysian Airlines flight MH370 and AirAsia Flight QZ8501 makes me think, "Can we really lose a track of an plane with the technology we have today?"
To answer this question, let's study how airplane is normally tracked!
The ATC - Air Traffic Control monitors the Airspace using two radars, primary and secondary.
The primary radar can detect and report position of anything that reflects it's transmitted radio signals including aircraft, birds, weather, land features, etc. Its targets don't have to co-operate, they only have to be within its coverage and be able to reflect radio waves. This radar only indicates the position of targets but it does not identify them.
Today the primary radar is just used as a backup or complementary system to the secondary radar.
This new radar relies on targets equipped with a transponder. The transponder is a radio receiver and transmitter which receives on one frequency (1030 MHz) and transmits on another (1090 MHz). Along with the position of target.
The secondary radar can request the altitude as well as the identity of the aircraft using the (IFF) Identification Friend or Foe System. Also, by monitoring successive transmissions, the speed and direction of the aircraft canbe determined. But once an aircraft is more than 240km (150 miles) out to sea, radar coverage fades away.
The only way ATC keeps in touch with the aircraft is high frequency radio.
So the answer is - Yes! We can lose a plane with the technology we have today.Wait, what about GPS? The aircraft uses GPS to show pilots their position on the map but this data is usually not shared with ATC.
Well, there's this new technology called as ADS-B, which means Automatic Dependent Surveillance Broadcast. ADS-B will help the aircraft to determine its position using GPS and relay data to the ground and other planes.
Unfortunately, as of now only 65% of all passenger aircraft are equipped with ADS-B.
The last option to track a plane in case of a plane crash is the Blackbox or Flight recorder. Each recorder has a device fitted to it known as an Underwater Locator Beacon (ULB). The device is activated as soon as the recorder comes into contact with water and it can transmit from a depth as deep as 14,000 feet. And the maximum detection range for 10 kHz transponder is 17-22 km in good conditions.
Also, to help investigators find them; a Black Box is not actually black at all, but bright orange!