In the last year, Pakistan has received over 70 UH-1 transport helicopters from the United States, as well over a hundred of night vision goggles (NVGs). Pakistan has always had a dozen or so UH-1s, and is thus familiar with the helicopters. The UH-1's the United States has sent are used, but in good condition. The U.S. Army is phasing out the UH-1, so the ones that are in the best shape are being shipped to Pakistan. Along with the helicopters and NVGs (Night Vision Goggles), has come training on how to perform air assault operations, both day and night. This is a capability the Pakistanis want to use against tribesmen along the Afghan border. The tribal gunmen do not usually operate at night, and can be more easily defeated with air mobile operations. Normally, when one group of tribesmen are attacked, they quickly radio for reinforcements, which arrive soon in pickup trucks and other vehicles. Often the tribal gunmen will start moving the minute they see army trucks traveling through the area. Going after a compound or village full of tribesmen via a helicopter assault defeats the tribal reinforcement system. If you can go in at night, you are likely to encounter less resistance, and be out of there with your prisoners before more armed tribesmen arrive, or even know you were there. This capability gives the army a psychological edge over the tribesmen as well, which is important in a region where much of the conflict is bluff and bluster. The American trainers were needed mainly to provide useful tips on large scale helicopters movements, and the use of the NVGs by the helicopter pilots. Night navigation in a helicopter can be tricky, even with the NVGs, but the Pakistani crews got up to speed quickly.