Malaysian officials have confirmed that a consignment of lithium-ion batteries was in the cargo hold of Flight MH370. “These are not regarded as dangerous goods,” said the CEO of Malaysian Airlines, Ahmad Jauhari Yahya, “and were packed as recommended by the International Civil Aviation Organisation.”

Little attention has been given to what was in the cargo hold of the Boeing 777, yet this would automatically be of interest to accident investigators. In this case the continued emphasis by the Malaysians on actions by the pilots and suspicions of a hijacking seem to have skewed the priorities.

The International Air Transport Association, IATA has pointed out that millions of lithium-ion batteries are safely carried by air every year. (The International Civil Aviation Organisation, ICAO, sets recommended safety standards while IATA represents airlines)

In the U.S., however, the Federal Aviation Administration’s Office of Security and Hazardous Materials Safety keeps a list of incidents involving these batteries. They include:

The hands of a passenger on a Southwest Airlines flight burned when spare lithium-ion batteries for a cell phone melted the zip-top bag in which they were carried, breached the passenger’s carry-on bag and produced smoke and flames.

A package of 18 lithium-ion batteries melted through their plastic wrap and set fire to their outer package at the UPS flight center in Louisville, Kentucky.

A FedEx pilot was taking the jump seat in the cockpit of a flight from Memphis when a lithium-ion battery in a flashlight carried in his backpack caught fire while the airplane was still at the gate.

The FAA cautions that their published list of scores of incidents does not represent all the information collected nor “all investigative or enforcement actions taken.”

As became apparent during a National Transportation Safety Board hearing last year into fires in the larger lithium-ion batteries used to power the systems of the Boeing 787 Dreamliner, even the manufacturers concede that the technology has not matured enough for them fully to understand how spontaneous meltdowns occur, either in a single cell or when one cell meltdown breaches its casing and spreads to another cell.

We don’t know what else was in the cargo bays of Flight MH370 but during any investigation by the NTSB everything on the cargo manifest would be carefully scrutinized and, given their record and the NTSB’s recent technical investigation of them, lithium-ion batteries would receive particular scrutiny. At the very least, until proved otherwise, cargo should be given equal weight with other scenarios as the possible cause of an accident.

International flights most likely to be carrying lithium-ion batteries are those originating in the countries that manufacture them, which include Malaysia, Taiwan and Japan.

Meanwhile, the search for the wreckage of the 777 ended a second day without finding any. This hunt involves an unusual alliance of intelligence, military and civilian resources.

Crucial to the first step of the search are the most heavily veiled of assets, the satellites. The search is being conducted in a part of the world, Asia, where the United States and China are devoting their most secret resources to watching each other.

Air Commodore John McGarry of the Royal Australian Air Force was carefully cryptic when discussing the images which have now concentrated the search far out into the ocean southwest of Australia. “The imagery has been progressively captured by satellites passing over various areas,” he said. No indication of whose satellites they were.

DigitalGlobe Inc, a Colorado company working for the U.S. government collected the images on Sunday. They passed them to the Australians, who released them late Wednesday EST.

The clock here is ticking with some urgency: beacons attached to the Boeing 777’s flight data recorders are already nearly half way through their effective battery life of 30 days. Not only that, but the pings sent out from the beacons to guide searchers to the location have an effective range of only five miles.

This might seem to be an inexcusably long lag in response time but it’s not as simple as that. Commodore McGarry pointed out that the output from the satellite has to be analyzed frame by frame, and covers a large area.

Just how seriously this information was treated is indicated by the fact that ships and airplanes began to be moved into the southern Indian Ocean on Tuesday.

Last week the Chinese released a satellite image of what they suggested might be wreckage from the Boeing 777 in the South China Sea. It was soon clear that it was not, and the Chinese then said that releasing the image had been a mistake.

The resolution of the images that are publicly released is probably a lot less than in the originals. The Chinese images were notably indistinct and those released by the Australians this week are little better. Sharpness of the image is an indication of how advanced the satellites are and the publicly released quality is quite likely degraded for security reasons.

The effectiveness of the search is heavily dependent on military airplanes given the mission of first confirming that what the satellite has pinpointed is actually the wreckage. There is a large area to be scoured and the amount of time the airplane can spend over its assigned zone is critical.

In the current search there is a marked disparity between the Australian and United States resources. The Australians are able to spend only two hours in the search zone. They are using Lockheed Orion P3s, which have been in service for 30 years and are derived from a 1960s airliner, the Lockheed Electra. Their fuel reserves allow them four hours to get there and another four to return. The United States is deploying the Orion’s successor, the Boeing P8 Poseidon that is derived from the Boeing 737 and can spend four hours in the search zone.

The age of the airplane does not, however, determine the sophistication of the search equipment on board. In their normal assignments they are submarine hunters. They are loaded with state-of-the art sonar and radar equipment. The search for the remains of Flight 370 is not simply a case of binoculars out of the window, although they play a part. Radar can sweep the zone as the airplanes fly a pattern of grids.

Right now 29 airplanes and 18 ships are involved in combing the area where on Sunday the satellite found the debris. The Boeing 777 disappeared eight days before. If the debris is from the airplane, currents and winds would have carried it far from the point of impact. That means that there will be two debris fields, one shifting all the time and one at the bottom of the ocean at a point yet to be found.

The Australians speak with awe of what they call the Great Southern Ocean. It is a remote and hostile place. Wave heights can be forty feet or more, the ocean bed is deep, between 10,000 and 15,000 feet, and the weather can be awful. The planet has few more inhospitable places than where MH370 likely went down.