Use a helicopter to spray pesticides

Although the use of spraying helicopters costs much more than the manual spraying method of farmers, but if comparing those costs with the results it brings as a result of killing the epidemic, saving crops on the surface wide or even a forest that is not damaged by pests will certainly be much more profitable.

Some countries around the world often use aircraft to spray pesticides, limiting a lot of damage. Russia uses AH-2 aircraft to spray. AH-2 is a propeller type, small speed, take-off road without length. Their fields are large, there is an airport on each area for aircraft to take off taking medicine.

In the early 80s of the last century, Vietnam imported 12 Soviet AH-2 aircraft, left at Vinh airport, but was hit by a big storm, destroying all of them, only recovering 2 so Do not use to spray medicine. On the other hand, the field in our country is small, using AH-2 spraying many places inappropriate.

In 1975, after recovering the number of American helicopters obtained at Bien Hoa airport, Comrade Nguyen Hong Nhi, the 372th Division Chief suggested that we make some aircraft for agriculture. Engineering Department Division has been working on improving an UH-1 helicopter for insecticide spraying. The initial work for us was no less difficult, despite being a technical soldier, but being an airplane technique, not familiar with the field and not understanding anything about spraying techniques.

UH-1 helicopter (Photo: mnangmuseum)

The design and manufacture of helicopter-based spraying equipment system is relatively simple, the medicine container is located in the abdominal cavity, the spraying system is installed in the lower abdomen, the rear side, the control system and the signal light effect in the cockpit for easy control of the pilot.

The principle of spraying is to use the exhaust gas of the engine, creating the pressure difference in the container from 0.2 to 0.3 KG / cm2, the difference is determined by a pressure sensor installed in the tank. contains medicine. When spraying, the pilot sees a green light, signaling in the tank that the medicine is turned on, the valve will open, the medicine is in the container under the pressure of the booster, through the valve running down the nozzle, spraying out . When the medicine runs out, the red light turns on, ending spraying.

The most difficult of designing and manufacturing spraying systems is the manufacture of nozzles. The requirement for spraying nozzle must reach blindness, that is, the size of the medicinal seed must be very small, the density of medicinal seeds must reach 15 to 20 seeds / cm2 to meet the requirements of killing.

To ensure these requirements, after fabrication, we invite the Southern Plant Protection Department to visit Bien Hoa airport, monitor and evaluate the results, determine the quality through water spraying test. . The officers of the Sub-Department have brought many 2x4cm glass panels to the airport, placed them on the runway and let the helicopters fly over to spray. Based on the quantity and size of water particles to assess the quality of the device. The first time the results were not good, the water particles were big, new to the dew, sparse density.

We adjusted the nozzle to continue testing to spray. Experiments must be done again and again until blindness is achieved. At that time, the officials of the Southern Plant Protection Department determined to meet the technical requirements of spraying.

At this point, the improvement of UH-1 helicopters for new pesticide application has been completed.

The Southern Plant Protection Department said that the use of spraying helicopters compared to propeller aircraft has the following advantages:

High mobility, no need for an airport, just need to land about 20 x 20m in the middle of the field, helicopters can go up and down to get the spray to fly.

When spraying, helicopters can fly low, under the effect of helicopters' wind created to turn the leaves to flip over and over, the drug can cling to both the upper surface, the underside of leaves and down to the stump, effectively kill higher worms and kill outbreaks quickly, not to spread to other places.

Nowadays, materials for making pesticide sprayers on the market are very available, we can produce them ourselves, not buy from foreign countries, and lower prices.

The installation of spraying equipment on helicopters is simple, easy, when it needs to be removed quickly, does not interfere with other activities.

The whole system is sealed, does not affect the health of the sprayer.

Using spraying helicopters can kill insects and other worms, limit the damage to crops.

The work of technical improvement has just been completed, meeting the occasion in Ba Tri district, Ben Tre province with rice borer, Southern Department of Plant Protection proposed 372 Division for helicopters to spray, thereby assessing actual results. Mr. Nguyen Hong Nhi, I and some officials from the Plant Protection Department in the South went to follow.

Nhi and I both sat on the helicopter, flying a few flights to see if fitting the control system in the cockpit was appropriate. The results obtained by the Southern Plant Protection Department are very good. After that, at the request of the localities, the Division also organized many flights to spray pesticides in some parts of the southern provinces, contributing to protecting crops for farmers to achieve good results.

Unfortunately, during that time, due to the need to fight on the southwestern battlefield, all helicopters had to focus on combat missions, the spraying of pesticides did not continue. And devices that have been researched and produced also turn into waste.

Although the use of spraying helicopters costs much more than the manual spraying method of farmers, but if comparing those costs with the results it brings as a result of killing the epidemic, saving crops on the surface wide or even a forest that is not damaged by pests will certainly be much more profitable. On the other hand, it also prevents the health of farmers when directly spraying on the field.

Currently, our army is using some types of helicopters, if the Ministry of Agriculture and Rural Development - Ministry of Science and Technology and the Ministry of Defense combine production of some pesticide spraying equipment, When there are epidemics, mounting on helicopters to spray drugs will put out the disease on a large scale. This is also a combination of economic tasks with defense.

Plants of the Air Defense - Air Force, such as A-42, A-41, can produce this equipment, if permitted by competent authorities.

For the sake of the country, even though I am 73 years old this year, I am willing to transfer the technology and convey the experiences that I have made where these devices are manufactured, without a cost. Come on.