According to the report on the website of the US "Star and Stripe" on January 28, more and more US and allied military personnel and contractors use phones and tablets to provide real-time maintenance advice to the Ukrainian army on the battlefield in encrypted chat rooms (usually through interpreters). According to the report, a soldier in the front line of Ukraine had trouble firing a 155mm caliber howitzer. So he asked a member of the US military maintenance team at a base in the southeast of Poland at the other end of the phone, "What should I do? What choice do I have?" The team member responded quickly and asked the Ukrainian to take down the rear of the howitzer, manually adjust the firing pin, and the shell could be fired. He did it and succeeded. It was reported that this exchange was one of the measures taken by the United States to expand the military aid line, with the aim of providing repair suggestions to the Ukrainian army in the fierce battle. For fear of being dragged into direct conflict with Russia, the United States or other NATO countries will not send troops into Ukraine to provide field assistance, so they turn to virtual chat rooms. The above-mentioned remote maintenance team said that the Ukrainian army on the front line frequently requested the repair of howitzers. The need to help operate weapons is also increasing. An officer said that one of the key issues is that the Ukrainian army has used these weapons to the limit, launched them at an unprecedented frequency, and continued to use them when the US military would have sent them for repair or elimination. The officer said: "They are using these weapons in ways we didn't expect. We are actually learning from them to see how much 'devastation' these weapon systems can withstand and where the limit is." Sometimes video chat is impossible. An American serviceman said: "Many times, if they are at the front line, they will not play video because the signal is not very good. They will take pictures and send them to us through chat, and we will sit there to analyze." He said that they have received photos of damaged howitzers, and the Ukrainian people will say: "This' M777 'exploded, what should we do?" He said that the Ukrainian people have recently mastered a new skill, You can reassemble the cracked guns. The US military said: "They didn't do titanium welding before, but now they do." He also said: "What was destroyed two days ago can be used now."