Less than a week later, on July 19, a civilian Mi-8 operated by a Russian company crashed at the NATO base in Kandahar, killing 16 passengers. The two crashes were the latest in a spate of fatal aviation incidents in southern Afghanistan in mid-July, underscoring the dangers faced by civilian aviators working on behalf of the U.S. and NATO in the contested region -- and by their passengers. The incidents also highlight the murky role Eastern European military contractors, who some might call "mercenaries," play in world conflicts.

The collapse of the Soviet Union in the early 1990s left thousands of former military helicopters scattered across the former Soviet republics. With the steady expansion of military and humanitarian operations in the Balkans, the Middle East, Central Asia and Africa over the past two decades, these abandoned helicopters found a new role. Small operators snapped up the choppers, and then offered them to NATO, the EU, the U.S. and aid agencies on a contract basis. Contract aviators also filled a niche staffing custom air forces, bought whole by embattled governments such as Chad's.

The demand for Eastern Europe's contract air forces stems from many Western nation's inadequate investment in helicopters, particularly heavy-lift models. "It is difficult to think of even a single mission that has enjoyed good quality -- or even adequate -- air support," Helmoed Römer Heitman wrote in the July issue of the Journal of International Peace Operations (JIPO).

Contractors have helped alleviate helicopter shortages, but not without paying a price -- in blood. Few contractors equip their choppers with the same defensive systems -- guns, flares and electronic jammers -- that are standard fit on government military aircraft in combat zones. "I don't think clients have requested any armament or other defensive measures which would significantly add to the cost of the contract," Doug Brooks, president of the Washington-based International Peace Operations Association, told World Politics Review.

In Africa, contract aviators face all the dangers associated with waging a major air war. Chad's air force is equipped with Soviet-designed Mi-35 attack helicopters and Su-25 jet bombers, most of them sourced from Ukraine. Many of the pilots are Ukrainians working under contract.

Chad's aircraft have been heavily involved in fighting that pits Chadian troops and militia against soldiers and militia from Sudan. The Su-25s even penetrated Sudanese airspace several times this summer while pursuing Sudanese militiamen. The latter managed to shoot down one of the Mi-35s last year, injuring its two Ukrainian crew. The wounded contractors reportedly hitched a ride back to their base on a military aircraft belonging to the EU peacekeeping force stationed in eastern Chad.

Contractors' involvement in military campaigns is often under-reported in the press, despite the high level of scrutiny directed at U.S. firms once or currently operating in Iraq -- including the former Blackwater, now known as "Xe." The lack of press coverage is consistent with the broader absence of strict government oversight. Pecotox Air, the Moldovan company whose Mi-26 was shot down in Afghanistan, managed to win its NATO contract despite being banned from EU airspace for safety reasons. The company has also been fingered in an arms-smuggling probe by the Stockholm International Peace Research Institute (SIPRI).

Indeed -- and perhaps not coincidentally -- the very countries where many aviation contractors are based are also responsible for much of the world's illicit arms trade. Sudan's separatist southern region sources its heavy weaponry from Ukrainian firms, via Kenya. SIPRI cites Russian, Ukrainian, Moldovan and Kyrgyz aviation firms as being connected to arms smuggling.

This absence of oversight is particularly vexing for aid agencies that rely on contract aviation in conflict zones. "No neutral authority exists to which donors and aid agencies alike can turn for unbiased counsel on sourcing aircraft and aviation services," Angelie Petersen wrote in JIPO. "Nor is there any internationally accepted resource for implementing or monitoring a code of conduct or operational standards in humanitarian aviation specifically. The lack of organized air logistics leaves the entire aid and donor community extremely vulnerable, not to mention the people they aim to serve."

The same might be said of the U.S. and NATO -- and of the diplomats and peacekeepers working to restore peace to Central Africa. Heavy reliance on ethically dubious contract air forces means greater risk for crews and passengers and for the operations they support -- and less accountability, when incidents occur and lives are lost.

**David Axe is an independent correspondent, a World Politics Review contributing editor, and the author of "War Bots." He blogs at War is Boring. His WPR column, War is Boring, appears every Wednesday.