Last year, alarmed at how vulnerable their peacekeepers were without helicopters, Ireland hurriedly leased two Mi-8 helicopters from a Ukrainian firm, for use in Chad (where a battalion of Irish were serving along the Sudan border). This was done in a hurry, as the news stories of how constrained the Irish troops were without a few of these aircraft for support, were arousing public anger. The original lease period was for ten months, which was later extended to 16 months.
At first, the Irish government was told this would cost $4.5 million. But later it was discovered that the total cost would be closer to $6.5 million (about $6,600 per helicopter per day). It was also discovered, after the helicopters were in Chad for a few months, that they were only licensed to carry cargo, not personnel (except in emergencies, like medical evacuation, or whenever the senior Irish officer in Chad wished to risk his career by insisting the choppers carry some of his troops.)
The haste with which the Irish Army made the lease arrangements was caused by another leasing deal, with a West European nation, that fell through at the last minute. The Ukrainians warned that it would be expensive to get two helicopters to the middle of nowhere (a description that fits eastern Chad) and maintain them there. Basically, it cost the Irish $3,100 per flight hour, plus the cost of war risk insurance.
The 11 ton Mi-8 is a 1960s design. This chopper is about twice the size and weight of the Vietnam war era American UH-1, but only hauls about 50 percent more cargo. Thus the Mi-8 can carry 24 troops, or four tons of cargo. The UH-1 was replaced by the UH-60 in the 1980s, while the Mi-8 just kept adding better engines and electronics to the basic Mi-8 frame. The larger interior of the Mi-8 is popular with many users. The Mi-8 can cruise at about 200 kilometers an hour and stay in the air for about four hours per sortie. Over 12,000 Mi-8s have been built, and nearly 3,000 have been exported.
A few years earlier, in an attempt to avoid a situation like Chad, the Irish military has bought six AW139s. Think of this as a modern version of the Mi-8. The eight ton AW139 can carry up to 15 passengers, and get by with just one pilot. Cruise speed is 288 kilometers an hour and endurance averages 3.2 hours. The AW139 is basically a civilian helicopter, while the Mi-17 is built to military standards. A military version of the AW139, the AW149, is in development, but won't be available for another 4-5 years. The AW139s were not sent to Chad because it was believed they were not robust enough to tolerate the harsh environment. The Mi-8s, on the other hand, had been operating in places like Chad for decades.