Posts Tagged ‘ping’

What you should Know About Malaysia Flt MH370

March 18, 2014

~~~~~~~~2c ~~~~~~~~2d

I am so sick of these TV experts! Here is what you need to know about Malaysia Flt MH370: Malaysian Airlines operates 17 Boeing 777-200ER Aircraft. Here are some specs:

Maximum weight 656,000 lb
Maximum landing weight 470,000 lb
Cruise speed 560 mph at 35,000 feet
Maximum range 8,892 miles.

At 1241 am Flt MH370 departed Kuala Lumpur International Airport for a flight to Beijing expected to take 5 hours and 49 minutes, 227 passengers and 12 crew members were on board.

At 0107, after take-off and climb toward assigned altitude of 35,000 feet, the plane sends its last ACARS transmission, which gives engine maintenance data to the ground.

At 0119: Someone in the cockpit said “All right, good night” to Malaysian air traffic control. Those were the last words heard from Flight MH370. By this time they would be about 300 miles from Kuala Lumpur.

At 0121: The plane drops off air traffic control screens as its transponder stops transmitting. The Civil Aviation Authority of Vietnam says the plane failed to check in as scheduled at 0121 with air traffic control in Ho Chi Minh City.

At 0215: Malaysian military radar plots Flight MH370 at a point south of Phuket island in the Strait of Malacca, about 300 miles west of its last known location. Phuket is in southern Thailand.

At 0811: Seven and a half hours after takeoff the last signal is received from the plane, according to satellite tracking data. The final communication placed the plane somewhere in one of two corridors: a northern arc stretching from northern Thailand to Kazakhstan, or a southern one stretching from Indonesia to the vast southern Indian Ocean.

So let’s analyze, within minutes of each other ACARS and then the Transponder were shut off. In addition the 777 made a turn to the west. The theories that there was a catastrophic failure makes no sense. The Transponder has triple redundant power and will work off the battery if all else fails. If the jet needed to land quickly, there are long runways all over Vietnam and Thailand, I have landed on most of them. Clearly, no aircraft flies for 7 or 8 hours after a catastrophic failure.

Some seem to think a pilot was despondent and wanted to commit suicide. Seriously, how long does that take? Do you have to fly to the far reaches of the planet to commit suicide?

Some think it was a terrorist takeover like 911. I think if any landmark had been destroyed by the 777, we would know about it. It could have involved terrorists or pirates and that has been my theory from the beginning. At least one of the pilots would most certainly have had to be in on the plot either voluntarily or coerced.

Somalia, Bangladesh, Pakistan and Iran come to mind. Did the 777 have enough fuel to make it to Somalia? Yes it did. The distance between Kuala Lumpur and Mogudishu is 3,896 miles. The distance from Kuala Lumpur to one of the most distant Military Air Bases in Pakistan, Risalpur is only 2,780 miles overflying India. India only operates Air Defense Radar on an as needed basis. You can be sure of one thing, if the pilots were involved, they would make sure they had enough fuel to reach destination.

Air Defense Radar is very good in China, Australia and Vietnam. I think we can rule out those locations or over flight of those countries.

We are down to only two possibilities, Flt 370 crashed or it diverted to some secret location. Both scenarios must be simultaneously investigated. If Pakistan Government Officials refuse to assist in the search for the aircraft, that would be a clue. Iran and Somalia are not going to cooperate. It is becoming more difficult for Somali pirates to hijack ships, they could turn to easy airline targets.

I don’t think the airlines in Iran or Somalia fly any 777’s. Various Airlines in Pakistan fly a total of nine 777’s.

So you will know more than the cutting age television talking heads, here are systems that communicate with outside entities:

ACARS is the acronym for Aircraft Communications Addressing and Reporting System. It’s an automated communication system used by commercial planes to transmit and receive messages from ground facilities (airline, maintenance department, aircraft or system manufacturer, etc). Therefore, along with the general information about the flight (callsign, speed, altitude, position, etc), these messages may contain what we can consider systems health checks.

ACARS is a service: airlines have to pay for it. It looks like Malaysia Airlines subscribed only to engine health monitoring that enabled MH370 to send data to Rolls Royce.  Is it possible Boeing was still getting the data anyway?

ACARS rely on VHF frequencies, in fact you can track planes and decode messages with a simple radio receiver tuned on the proper ACARS frequencies and a software running on your computer or SATCOM (SATellite COMmunication). Although this is still debated, according to several pilots the ACARS transmissions can be switched off by the pilot from inside the cockpit, by disabling the use of VHF and SATCOM channels. This means that the system is not completely switched off, but it can’t transmit to the receiving stations.

SATCOM is a radio system that uses a constellation of satellites used to transmit voice, data or both. ACARS can make use of SATCOM to transmit its data to ground stations. Dealing with ACARS, the SATCOM system used by MH370 was linked to the INMARSAT network. INMARSAT is a British satellite telecommunications company that offers global services through a constellation of three geostationary satellites. The system relies on “pings”.

A Ping is a quite common term for IT Networking. It refers to a utility used to test the reachability of a host on an IP network and measure the round-trip time of the packets .

Similarly to what happens on a Local Area Network, satellites send pings once a hour to their receiving peers that respond to it thus signaling their network presence. Hence, these pings are no more than simple probes used to check the reachability of SATCOM systems aboard the planes.

From the analysis of the time between request and response it is possible to work out the distance of the plane from the satellite allowing investigators to work out two possible locations along an arc. I doubt very seriously that most pilots know their system responds to the pings when it is shut off.

Based on details recently disclosed, the last response to a satellite ping, was sent by the SATCOM aboard MH370 at 08:11 AM Malaysia time, over 7 hours after the loss of contact with the Boeing 777. The jet may have flown up to 59 minutes more or a total of almost 8 1/2 hours. Between 7 1/2 and 8 1/2 hours the jet may have flown between 3,500 and 4,200 miles from Kuala Lumpur.

Finally, if the 777 is located using intelligence, satellite or anonymous tip, don’t expect it to be breaking news. The governments will likely formulate a plan of action before releasing any potentially classified information. Keep your eyes and ears open.