Micronair AU4000 Rotary Atomiser

Micronair AU4000 Rotary Atomiser for Aerial Application

The AU4000 is a precision engineered rotary atomiser designed specifically for use on agricultural aircraft for specialised ultra low volume (ULV) spraying operations.  The large diameter gauze assembly and durable bearings are designed for continuous operation at the high rotational speeds required to produce the small droplets necessary for environmental health, migrant pest, forestry and similar ULV spray applications.

The atomiser is driven by the airflow past the aircraft through five highly efficient fan blades.  These are adjustable in pitch, enabling the rotational speed to be varied to produce the required droplet size.

The atomiser is fitted with an electro-magnetic brake to prevent rotation when flying outside the spray area.  This minimises the drag of the atomiser during long ferry flights and maximises bearing life.

AU4000 atomisers are suitable for installation on a wide range of aircraft types, including modified fast utility aircraft.  Different lengths of fan blades enable the atomiser to be used on aircraft operating at speeds between 80 – 240 km/hr (75 – 150 MPH).
Ideal for Specialised ULV Application

Applications such as environmental health spraying (fly and mosquito control), spraying of migrant pests (locust, armyworm etc.) and forest pest control require the production of a narrow controlled spectrum of small spray droplet sizes.

The AU4000 atomiser uses a large diameter rotating woven wire cylinder to produce the spray droplets.  The large surface area of the gauze allows the atomiser to handle a wide range of flow rates and is not liable to blockage, even with viscous liquids or formulations with a high solids content (such as some biological insecticides).

Precise flow control

The flow to each atomiser is controlled by a variable restrictor unit (VRU).  This provides finger-tip control of the flow by a simple turn of the knob and eliminates the need to dismantle or change individual restrictor orifices.  Overall flow from the aircraft is regulated by boom pressure in exactly the same way as a conventional spray system, with chemical feed to the atomiser from a 3/4″ (19 mm) id hose or 7/8″ UNF fitting.  Every atomiser is supplied with a diaphragm check valve and a secondary shut-off valve inside the unit.  These ensure immediate and precise liquid shut-off at the end of each spray run and eliminate the risk of chemical leakage on the ground.

Optional Atomiser RPM to GPS Interface

The AU4000 is compatible with the optional Micronair RPM Indicator to GPS Interface which measures the rotational speed of up to ten atomisers and transfers this data to any compatible* GPS guidance system via a serial (RS-232) port. Atomiser RPM is shown on the GPS display screen and can also be included in the GPS log file. Logged RPM can be reviewed after flight alongside other application parameters using the GPS log replay software.

*Consult your GPS system supplier for compatibility details. Both the GPS processor and the PC based log replay system must be running the necessary software. The GPS system unit must have one free serial port.

Spray Pod System

Micron Group manufactures a completely self contained spray system consisting of a pair of underwing pod tanks fitted with AU4000 atomisers, pumps and controls. The system can be installed on any high-wing aircraft with suitable under-wing pylons. The only permanent modification to the aircraft is the installation of electrical wiring to a removable control panel in the cockpit.


AU4000 Brochure (English) (PDF 225 Kb)

AU4000 Handbook (English) (PDF 1118 Kb)

Micronair Aerial Product Range Brochure (English) (PDF 1419 Kb)

Boom Clamp Dimensions & Templates (PDF 337 Kb)

Public Health Catalogue Micron-IK (English) (PDF 3578 Kb)

Public Health Catalogue Micron-IK (Español) (PDF 2300 Kb)

Public Health Catalogue Micron-IK (Français) (PDF 2301 Kb)

Public Health Catalogue Micron-IK (Português) (PDF 2894 Kb)

Public Health Catalogue Micron-IK (русский) (PDF 3190 Kb)

Public Health Catalogue Micron-IK (Arabic) (PDF 7072 Kb)


Weight:  2.8 kg (6.4 lb) without mounting clamp or block. 
Mounting: By mounting clamp or block types available to suit Micronair installation kits and popular boom sections.  
Liquid throughput: 0 – 30 L/min (0 – 8 USG/min) per atomiser
Flow control: By variable restrictor unit (VRU).
Liquid shut-off: By diaphragm check valve and internal secondary shut-off. 
Rotational speed:  Adjustable five bladed fan running at 2000 – 10000 rpm (maximum)
Operating airspeed:  80 – 240 Km/Hr (75 – 150 MPH)  
Droplet size:  Variable between 30 – 400 microns VMD 
Brake: Electro-magnetic brake 24V DC 20 W 

Note: Above figures are for guidance only.  Performance will vary according to chemical formulation and conditions of use.  See AU4000 Handbook for full details.