The In-flight Aerosol Spectrometer 11-S

Ultralight airplanes, helicopters, helium balloons or jets – the GRIMM aerosol spectrometer 11-S (Sky-OPC) was especially developed for compensating the changing air pressure during the operation in high and changing altitudes and delivers precise measurement values in real-time. The particle measurement and calibration procedure is the same as for the 31 size channel spectrometer 11-R. The built-in differential pressure sensor, which is combined with an external pump, provides full flexibility when measuring in the troposphere.
Flying speeds of a slow flight microlite or a fast jet do not present a problem for the 11-S. The GRIMM sample probes are especially geared to the type of aircraft and therefore ensure individual measurements without limitations.
This allows customers to create vertical profiles of aerosols in various altitudes. It can even be combined with gas sensors to explore the source of aerosols in the clouds.


  • Real time measurements of aerosol particles and droplets
  • Sample flow independent on atmospheric pressure
  • Easy to install and maintain due to docking station
  • 31 size channels within 6 seconds
  • Fast scanning down to 1 second
  • Particle number and mass distribution and PM values
  • rinsing air for protecting laser and detector in optical cell
  • Optional pressure, humidity and temperature sensors
  • total inlet flow (1.2 L/min) analyzed in optical cell
  • easy and secure handling due to docking station
  • self-test of all optical and pneumatic components for highest quality standards


  • Airborne measurements with airplanes, helicopters, balloons...
  • Tropospheric research
  • Vertical Profiling
  • Measuring cloud droplets
  • Fixed station monitoring
  • Sciencitfic aerosol studies

Technical Data

measured values

particle size and mass distribution

particle size range

0.25 - 32 μm

size channels


particle number

0 - 3 000 000 particles/liter

dust mass

0 μg/m3 - 100 mg/m3


>97% of total measuring range

particle detection principle

light scattering at single particles with diode laser; detection volume aerodynamically focused, no border zone error

time resolution

6 s (standard), 1, 2, 3 s (fast mode)

volume flow rate

1.2 L/min, with external pump volume controlled by critical orifice

rinsing air

0.4 L/min, with internal pump volume controlled by critical orifice


PC with GRIMM software


RS-232, PCMCIA memory card

analog input

1 port (0 - 10 V) for external sensors

power supply

in: 12 VDC, 24 VDC optional

operating conditions

0 to +40°C (32 - 104°F), RH < 95%, non-condensing, non-corrosive, or explosive gases

absolute pressure range
120 - 1100 mbar

storage and transport

-20 to +50°C (-4 - 122°F), RH<95%

dimensions (hxwxd)

docking-station 7.2 x 18.2 x 25.5 cm (2.8 x 7.2 x 10 in)
spectrometer 6.0 x 16.0 x 25 cm (2.4 x 6.3 x 9.8 in)
complete: 7.2 x 18.2 x 25.5 cm (2.8 x 7.2 x 10 in)


docking-station: 1.3 kg (2.9 lbs)
spectrometer: 1.6 kg (3.5 lbs)
complete 2.9 kg (6.4 lbs)


1119Sky Straight connection pipe, length 15 cm


External membrane vacuum pump, 230V / 50Hz or 115V / 60Hz, 65W, 6.0L / min, 100mbar (U01N86KN18) only for SKY OPC


External diaphragm vacuum pump, 24 VDC, max. 11.6 W, 8.0 l / min, 230 mbar (X412991) only for SKY OPC


External piston vacuum pump 12 VDC, 15.8 l / min, 39 W, -800 mbar max. (U0180061068) only for SKY OPC

1144C Carrying case with foam inserts for 11-S
1152 Isokinetic sampling probe for flow rates from 2 to 25 m/s


external sensor for temperature and relative humidity


capillary diluter (1:10 or 1:100)


GRIMM developed a powerful software to visualize, process, and import as well as export your valuable measurement data.
This easy-to-use program is compatible to Windows XP and all later versions.

Please contact us for your for free trial version if you already own a GRIMM measurement device or more information if you are in the process of finding your measurement solution.


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