October 19, 2018:
In September 2018 the U.S. Air Force finally found a replacement for its aging UH-1N transport helicopters. The new helicopter is the MH139, a militarized version of the AW139. The air force will pay $29 million each for 84 helicopters. The MH139 is similar to the HH139 version of the AW139 already in use by the Italian Air Force. The existence of the HH139 cuts the cost of meeting the U.S. Air Force requirements (lots more electronics) for the MH139.
The AW139 is widely used for SAR (search and rescue) and Medevac (medical evacuation) missions and has been ordered by dozens of nations because of those capabilities. AW139 transport helicopters are built by Anglo-Italian firm AgustaWestland, which has a major plant in the United States that manufactures nearly a quarter of all AW139s. The standard AW139 cost $20 million and up each depending on accessories and support contracts.
These eight ton choppers carry up to 15 passengers and can get by with just one pilot. They have a very large cabin and can hold up to four stretchers, which is one reason it is so popular for medevac. Cruise speed is 288 kilometers an hour and endurance averages 3.2 hours. The AW139 competes with the U.S. UH-60 and another European helicopter, the slightly larger NH90. Entering service in 2003 nearly a thousand AW139s have been delivered or are on order so far.
The decision to buy the MW139 ends an awkward situation for the Air Force. That was because the search for a UH-1N replacement had been something of an embarrassment. In 2013 the air force decided to refurbish some or all of its UH-1Ns for another decade or more of service. Six years of failed efforts to find an affordable replacement, and growing budget cuts, gave the Air Force little choice. At the same time, the air force was encouraged by successful efforts by the U.S. Marine Corps to keep similar UH-1Ns flying. The Air Force currently has 62 UH-1Ns, used mainly for patrolling the large tracts of land surrounding ICBM silos and providing transportation. The main difference between the basic Vietnam War era UH-1 and the UH-1N was the use of two engines in the latter. This made the five ton UH-1N safer and more reliable, which was the main reason the Air Force went with this model. The UH-1N could also carry a few more passengers.
Since 2007 the Air Force has been looking for 80-90 new helicopters to replace the UH-1Ns. That search failed because new birds that could match the UH-1Ns were too expensive. It's turned out to be cheaper to rebuild the UH-1Ns, at least until an affordable replacement could be found. The air force revived the search in 2015 with orders from the Air Force commander to find a replacement or else. Thus encouraged the AW139 was eventually found to be what earlier searches had failed to locate. But since the first MH139s won’t arrive until 2021 the UH-1Ns will still be flying for another five years or so.
The Marines have long used UH-1Ns and came up with a remanufacturing program for them, which converted UH-1Ns to UH-1Ys. In the end the marines decided to buy 92 newly built UH-1Ys for $27 million each. The Marines offered 25 of their UH-1Ns to the air force as a source of spare parts or, after refurbishment, to replace losses.
Meanwhile, the U.S. Army and Navy have largely replaced all their UH-1 transport helicopters, mainly with the UH-60 starting in the 1980s. This 10.6 ton helicopter could carry more and was safer to operate. In 2007 the 3.6 ton UH-145 was introduced, this replaced the remaining UH-1s in army service (by reserve units who did not need something as large as the UH-60). Only the Marines and Air Force still uses the UH-1, in the form of the twin-engine naval version. The UH-60 was offered as a replacement for the air force UH-1Ns but lost out to the cheaper and popular (with similar users) AW139.
The half-century old UH-1 ("Huey") is fading away but is still widely used. Over 16,000 UH-1s were built and over 4,000 were lost during the Vietnam War. Over a thousand UH-1s are still in service. The UH-1 was actually a military version of a civilian helicopter (Bell 204) design. Both remained in production through the 1980s, with over 12,000 204/205s being produced. The 4.3 ton, single engine, UH-1 could carry 2 crew and 11 troops and was the first military helicopter to use gas turbine (jet) engines. This allowed a lighter helicopter to carry more weight. The UH-1 served the army for 50 years, although since the 1990s most served in reserve units. The twin-engine UH-1 was originally developed for the Canadian military and later adopted by the U.S. Navy, Marines, Air Force, and many foreign countries who were willing to pay a premium for the additional safety of two engines.