Unfortunately, the LUH has just encountered its first spot of trouble. The Associated Press reports that during flight tests in Southern California in 80-degree weather, cockpit temperatures in the UH-72A Lakota rose above 104 degrees, the designated critical point for communication, navigation and flight control systems…
A July 2007 report to the Army said that no cockpit equipment failed during testing, but the aircraft is considered “not effective for use” in hot environments until the military adds air conditioners to the helicopters. Civilian helicopters like the EC145 from which the Lakota is derived use air conditioning, and experience no problems with hot environments as a result. In contrast, military helicopters generally do not include air conditioning because adding them reduces available power, and increases their maintenance overhead.
The issue is the first example of the Army mis-estimating the factors involved in taking a commercial off the shelf helicopter and adapting it for military use – an issue that has plagued the Bell 407-derived ARH-70A helicopter almost from its inception. While the LUH program was designed to buy helicopters solely for use at home and far away from combat zones, there had been talk of changing that and creating a more flexible fleet of UH-72 helicopters that could fill various roles as needed. The latest issue, and the proposed resolution, makes that flexible fleet future less likely.
UH-72 Lakota: Hot n? High
LUH-72 Issues
The issue is not that EC sold the Army a bad bird. The issue is that bean counters at higher levels within DA considered the A/C a luxury item and deleted it. The A/C does not keep up out there, because there is not one. There is a ventilation system, but not an A/C like the rest of us are used to. Not to mention 2 other key issues. The avionics are not certified to work above 95F OAT and the doors cannot be open in flight except when performing hoist ops. The TH-67 initially came with A/C. The Army then paid to have them removed before acceptance. Due to airframe issues caused by the doors being removed multiple times per day, they then paid to have A/C reinstalled on the initial fleet and all future deliveries.
The AH-1 and the AH-64 systems were sold as an Environmental Control Unit (ECU). These 2 aircraft have no window that can be opened in flight. The OH-58D started out with an ECU, but some nitwit changed the wording to reflect an A/C. Yet, it is loaded with avionics that constantly overheated during Desert Storm.
Early OH-58Ds still have a mount for the A/C on the power accessory gearbox. It was direct drive, and not piggybacked off of the TR driveshaft like the TH-67.
There are a lot of missions in the hot months due to heat injuries of course. Too bad the bean counters valued a few dollars over people's lives.
Fortunately, many of these aircraft are going to VIP units. It will not take but a few VIP flights before we get an A/C. I just wonder how much more it will cost for it to be installed as an add-on.
On another note, as readers posted, this is not the 1st venture into FAA certified aircraft by the Army. There are currently about 200 N numbered (FAA registered) TH-67s at mother Rucker. And, they have not been maintained to FAA standards; but that is a whole other issue.
Air conditioning is standard in commercial versions of the aircraft, which have not had overheating problems. But the military usually avoids air conditioning in military aircraft to reduce weight and increase performance.
"We don't need air conditioning in the Blackhawks, so we didn't think it would be an issue" in the Lakota, McCuin said. "But when we got the helicopter into the desert, we realized it was a problem."
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