Boeing 747 is a type of airplane that is used to transport people and things from one place to another. Sometimes, unfortunately, these airplanes can be involved in accidents, which can cause damage to the main body of the plane, called the "hull." When such accidents happen and the damage to the hull is so severe that it cannot be repaired, we call it a "hull loss."
Let's imagine you have a toy airplane made of Lego. Normally, you can build and rebuild your Lego airplane whenever it gets damaged. But sometimes, if you accidentally step on it or it falls from a high place, it might break into so many pieces that you cannot put it back together. In that case, you might say, "Oh no! My Lego airplane has had a hull loss!"
Similarly, when a Boeing 747 airplane is involved in a serious accident, like crashing into something or having a very bad landing, the damage can be so severe that the entire hull of the airplane is destroyed. This means the airplane becomes useless and cannot be fixed anymore. It's like when your Lego airplane gets smashed into many small pieces that cannot be put back together.
Hull losses are very rare because airplane manufacturers, like Boeing, design their planes to be very safe. They have many special features, such as strong materials, safety equipment, and backup systems to prevent accidents. However, accidents can still happen due to things like bad weather, human errors, or technical problems.
So, when we talk about Boeing 747 hull losses, we mean the very unfortunate accidents where the airplane's main body is so damaged that the plane is no longer usable and cannot be repaired. These accidents are very sad and can cause a lot of harm, but thankfully they are very uncommon.