DeHavilland Twin Otter: TNRCC/Baylor University

                                                                                                                                               

 

Endurance: 3.5-4 hrs

Ceiling: 2.5 km

Payload: 3200 lbs

Research Speed: 150 kt

 

 

Aircraft Instrument Package for the Baylor Twin Otter – 2000 Season

 

Parameter

Time Resolution

Method

Det. Limit

Ozone (O3)

5 second poll of

10 second updates

Ultra Violet (UV) Photometry/Absorption

 

 3 ppb

Ozone (O3)

1 second poll of 2 second updates

Sample reacted in a constant concentration nitric oxide (NO) gas stream, (i.e. NO titration), and Chemiluminescence

 3 ppb

Sulfur Dioxide (SO2)

1 second poll of

2 second updates

UV Pulsed  Fluorescence

 

 1 ppb

Nitrogen Oxide (NO)

1 second poll of

2 second updates

Chemiluminescence

 

 2 ppb

Total Reactive Oxides of Nitrogen (NOy)

1 second poll of

2 second updates

Molybdenum (Mo) calalytic sample reduction at 320 oC and Chemiluminescence

 

 2 ppb

Total Nitrates

(i.e. Nitric acid plus particulate and/or aerosol nitrates)

 

1 second poll of

2 second updates

Nylasorb filter then molybdenum (Mo) catalytic sample reduction at 320 oC and Chemiluminescence. The resulting measurement, NOy*, (i.e. NOy less the nitric acid and particulate/ aerosol nitrates) is subtracted from the NOy measurement result.  The difference equals the total nitrates.

 

 2 ppb

Nitrogen Dioxide (NO2)

1 second poll of

2 second updates

UV Photolysis with Chemiluminescence

 

 2 ppb

Carbon Monoxide (CO)

1 second poll of

1 second updates

Vacuum Ultra Violet, (VUV) Fluorescence

 

2 ppb





Light scattering               (red, green and blue wavelengths)                  (particle scattering (bsp) and backscatter)

 

5 seconds

 

Integrating  Nephelometer

1 * 10 x e-6 m-1

Particle Sulfate (SO4)

 

Semi-continuous

 2 minute updates

 Flash Volatilization            

5 ug/m3

Particulate matter less than 2.5 microns  in diameter (PM 2.5)

 

Mass

 

* Elements

 (38-40 see list)

 

Sulfate: SO42-  

Nitrate : NO3-

Chloride: Cl-

 

discrete filter

(47 mm Teflon and

37 mm Quartz)

URG Filter Pack

 

 

Gravimetry

 

X-Ray Fluorescence

 

 

Ion Chromatography

Ion Chromatography

Ion Chromatography

 

 

 

15 ug/filter

 

0.01B 0.86

ug/filter

 

1.5 ug/filter

1.5 ug/filter

1.5 ug/filter

Volatile Organic Compounds (VOC)

discrete grab in

SS canister

TNRCC OAL Gas Chromatography/Mass Selective Detector (MSD)   

 

0.2 ppbv

Volatile Organic Compounds (VOC)

discrete grab in

SS canister

On-Site Gas Chromatography/Mass Spectroscopy      

10 pptv

Altitude 

5 seconds

 

Barometric Pressure

Transducer

1 hPa

Latitude and Longitude

5 seconds

 

Global Positioning System (GPS) Garmin Model 150 Interfaced to the Air Data Computer

0.04 seconds of Latitude and/or Longitude

Wind Direction

5 seconds

Shadin ADC 200

5 Degrees

Wind Speed

5 seconds

Shadin ADC 200

5 Knots

(5.76 mph)

Outside (Ambient) Air Temperature

5 seconds

Type AT@ Thermocouple

0.01 Degrees Celsius

Cabin Air Temperature

5 seconds

Type AT@ Thermocouple

 

0.01 Degrees Celsius

Dew Point

5 seconds

Chilled mirror optical hygrometer

(Buck Model 1101B)

 

0.001 Degrees Celsius

Relative Humidity

5 seconds

From the inlet of the TSI 3 wave Nephelometer

0.1%