KUALA LUMPUR: INITIAL concerns as to who has Malaysia Airlines MH17’s flight data recorders have been replaced with a sense of guarded optimism now that it has emerged that the pro-Russian forces are in possession of the crucial evidence.

Rebel leader Alexander Borodai said the black box from the downed airliner was recovered by his forces yesterday.

A screen grab from a Reuters video clip showed a rescue worker decked out in a Ukrainian Emergency Ministry uniform carrying a black-tipped orange box, consistent with that of a flight data recorder.

Borodai said his forces would hand over the black box to the International Civil Aviation Organisation (ICAO) but stopped short of saying when.

The rebel leader also said he was expecting a team of 12 Malaysian experts and that he was disappointed at how long they had taken to arrive.

He insisted that his forces had not interfered with the crash investigation, despite reports to the contrary by international monitors and journalists at the crash site.

Both Ukraine and pro-Russian rebels had accused each other of firing the Buk SA-11 surface-to-air missile that brought down the Boeing 777-200, tail number 9M-MRD, over Donetsk in eastern Ukraine on July 17 with the loss of all 298 lives on board.

Ukraine had accused Russia of sending sophisticated arms to the rebels, a charge Moscow denies.

The US embassy in Kiev issued a strongly-worded statement yesterday pointing to Russian complicity in arming the rebels.

It said “Flight MH17 was likely downed by an SA-11 surface-to-air missile from separatist-controlled territory in eastern Ukraine”.

It added that over the weekend of July 12-13, “Russia sent a convoy of military equipment with up to 150 vehicles, including tanks, armoured personnel carriers, artillery, and multiple rocket launchers” to the separatists. The statement also said Russia was training separatist fighters in southwest Russia, including on air defence systems.

Immediately after the shootdown, confusion reigned as to the status of the black box. Initial reports said it had been recovered and flown back to Moscow. The Kremlin issued a denial.

However, soon after, the governor of eastern Ukraine’s Donetsk region was quoted as saying that Ukraine’s emergency services had found two black boxes at the crash site of the downed Malaysia Airlines flight MH17.

“The black box was found by our emergency services. I have no information on where these boxes are at the moment,” Kostyantyn Batovsky had told the Interfax-Ukraine news agency.

Investigators were concerned that the integrity of the black box would be compromised, especially if it had fallen into the hands of the faction that had ordered the shootdown.

The flight data recorder measures some 200 individual flight parameters, including the aircraft’s heading, altitude and airspeed. Pitot probes located outside the aircraft would measure the temperature, barometric pressure and humidity, along with scores of other information.

Also recorded would be g-forces, engine settings, revolutions per minute, exhaust gas temperature, fuel burn, fuel and oil pressures and the aircraft’s attitude, or orientation in flight.

More importantly, it would indicate the aircraft’s last position and the forces exerted on the airframe the moment the missile impacted it from 33,000 feet below.

Investigators believe the cockpit voice recorder (CVR) holds the key to new questions that had been raised over the last few days, including why MH17 had diverted from its original flightplan and flown deeper into the conflict area, instead of away from it.

The CVR would record the last few minutes of conversation in the cockpit and would tell investigators if there was a conversation pertaining to a change in the flight route, and if the aircraft had been shadowed by a pair of Ukrainian fighters moments before it was shot down.

This report had been corroborated by testimonies from independent eyewitnesses.

Observers are concerned, however, that answers will not be forthcoming. The BBC had earlier reported, quoting Interfax news agency, that Ukraine’s SBU security service had confiscated recordings of conversations between Ukrainian air traffic control officers and the crew of the doomed airliner, very soon after the tragedy.

Radar recordings the New Straits Times mined from FlightAware.com showed that while recent routes taken by MH17 were further south of the Donetsk region, cutting across the zone above the Sea of Azov, the flight on that fateful day showed a 10° course change to a new heading of 117°, which took it straight above Donetsk.

It has emerged that flight MH17 had initially filed a flightplan requesting to fly at 35,000 feet above Ukrainian territory.

On entering Ukrainian airspace, however, the pilots were instructed to fly at 33,000 feet by local air traffic control “due to other traffic”.

The radar reading showed how the flight broke away from the usual route to move 300 miles to the north.

Data reading of an earlier MH17 flight, flying on July 16, showed that it had flown well inside the Russian border and near the Caspian Sea when it changed its heading to 117°, the track where 9M-MRD was brought down by a surface-to-air missile the next day.