Restoring Ancient Loa crossbow

Lieutenant Pham Vu Son and his colleagues from the Vietnam Military History Museum in collaboration with the Southeast Asia History Research Center have conducted research and reconstruction of the shape, size and operation principle of the nose. Co Loa name and the machine to shoot cross-continent Chau Chau more than 2,000 years ago.

This result also contributed to decoding the power of the 'magic crossbow' in the history of fighting against foreign invaders in Vietnam and bringing to the team the second prize of the Xth National Technical Innovation Contest (2008-2009).

Restoration of a cross-shot machine of Chau Chau

Senior Lieutenant Pham Vu Son said, since 2005, when exposed to the copper arrows collected by the Vietnam History Museum from the excavation of Cau Vuc vestige in Co Loa citadel (Dong Anh, Hanoi), he and colleagues are surprised and excited. Because, in addition to the legend of the miraculous power of arrows and magic crossbows, the captured arrows also have three edges, completely different from the previously collected arrows.

This difference led the research team of the Vietnam Military History Museum and Dr. Nguyen Van Viet, Director of the Center for Southeast Asian History to conduct an experimental study, verifying the 'power' of the nose. Co Loa's name and the name of Dong Son culture. 'If we can prove the legend, we will partly understand more about Vietnamese military art over 2,000 years ago,' said Lt. Pham Vu Son.

Since then, the research team has begun to collect materials for images of crossbeams, crossbows in collecting documents from Dong Han, Tong (China) and drawings on Ngoc Lu drums (dating back to more than 2,000 years ago, at the same time as the birth of An Duong Vuong's legendary crossbow) .

Through spectral analysis, the research team found that the composition of the Co Loa copper arrow has 95% in bronze; lead 3.4 - 4.2%; tin 1 - 1.1%. According to the explanation of the research team, the name is made from copper alloy because it has a high hardness, can be honed, honed to form parts of the blade, sharp, sharp, high damage. Tin and lead will make the arrow mold very dry, not sticking.

Experimental arrow shooting of Loa and a cross-firing machine at the Vietnam Military History Museum.Photo provided by Vietnam Military History Museum

This is the basis for the research team to find materials to make copper arrows. The casting of the arrow complies with the traditional manual method and is carried out by the bronze casting artists of Dai Bai village (Gia Binh district, Bac Ninh). In addition, the arrow body is also made from the old body by the research team, because the body of areca has no burning, it is possible to make the arrow body of a certain length, the wood is flexible, straight, without shrinkage, warping. The whole arrow is 80 cm long, 0.8 cm diameter, weighs 80-100 g.

During the construction of the arrow, the research team also sought to build prototypes of the inter-European crossbow machine (firing multiple names at the same time). From the crossbows collected in Hoa Binh, Nghe An and models of crossbows on Angkor Wat reliefs (Cambodia), the research team has collaborated with workers who make crossbows of Muong try to build personal crossbows and crossbows in Van Lang - Au Lac. Initially recovering a kind of cross-shot machine that can fire one and many copper arrows at the same time.

Decode power 'magic crossbow'

After completing all the arrows and shooting machines, the research team conducted a test shot and verified the strength and power of the arrows fired at the place to build the crossbow machine in Hoa Binh. Initially, the steles were made of banana stalks, porous plaques located at a distance of nearly 100 meters, when shot with a machine, the arrow passed through the target. The distance of the stele is translated to verify the damage effect of the arrow. The test results show that the arrow can fly about 100 - 120 m, but the damage range, the arrow is the most powerful at a distance of 60 - 80 m.

In addition, the An Duong Vuong's 'magic crossbow' is mainly used to fight against city attacks, the opponent must pass a deep trench around the city, so the study of the characteristics of people standing up from above also be noted. According to the researchers, usually the line of sight to shoot about 10 degrees compared with the straight line will bring the highest efficiency.

Through studying the marks left on the beer after each shot, the team found that the three-sided warhead while flying to twist to reduce the resistance of the air, the projectile was stable, when hitting the target within Nearly there is the possibility of 'skewers' causing mass damage.

In addition, the three-sided arrow creates a large tear in three directions, causing rapid bleeding, massive casualties for the enemy. This is an important trait that makes the opponent panic and lose his temper while attacking and is a factor in the 'miracle' of An Duong Vuong crossbow compared to contemporary weapons and even with the type of crossbow only fired by arrows with two normal edges.

The verification of the effectiveness of the Co Loa arrow arrow and the inter-continental cross-shot machine was also carried out at the Vietnam Military History Museum. This study was also awarded the Second Prize by the Organizing Committee of the National Technical Innovation Contest.