Simultaneous inboard and outboard, inflight measurements of ultrafine particle concentrations

Figures & data

Figure 1. Schematic representation of CPC comparison experiments.

Figure 2. Example of a single diameter ammonium sulfate aerosol sampled by the two candidate CPCs at five different concentrations spanning three orders of magnitude.

Table 1. Summary of all flights and data coverage from cabin sampling.

Project name	Flight No.	Date	Inboard CPC	Outboard CPC	AMS	Pressure correction	Approach UFPs
VANAHEIM	B983	13 October 2016	Some	Yes	No	Yes	No
	B985	17 October 2016	Yes	Yes	No	Yes	No
	B986	17 October 2016	Yes	No	No	N/A	N/A
	B987	18 October 2016	Yes	Yes	No	Yes	Yes
	B988	20 October 2016	Yes	Yes	No	Yes	Yes
	B989	20 October 2016	Yes	Yes	No	Yes	No
	B990	21 October 2016	Yes	Yes	No	Yes	Yes
	P153 (transit)	21 October 2016	Yes	Yes	No	Yes	Yes
MOYA	C003 (transit)	27 February 2017	Yes	Some	Yes	No	Yes
	C008 (transit)	03 March 2017	Yes	Some	Yes	No	No
CLARIFY	C040 (transit)	26 August 2017	Yes	Yes	Yes	No	Yes
	C041 (transit)	26 August 2017	Yes	Yes	No	No	Yes

Figure 3. Time series of particle number concentration inboard and outboard and altitude from flight B989. Also shown are the take-off and landing times. X-axis is limited to 6 × 10⁴ cm⁻³, not the full scale of the 3786 CPC range.

Figure 4. Time series of particle number concentration inboard and outboard and altitude from transit flight P153, with minimal science activity on board. Also shown are the take-off and landing times.

Figure 5. Organic mass spectra from flight C003 during take-off (top) and landing when both CPCs were high (bottom).

Figure 6. Time series of particle number concentration inboard and outboard, altitude, and AMS organic mass concentration from flight C008 showing a fume event. The insert is an expanded section of the flight on approach/landing. Vertical dashed lines denote take-off/landing.

Figure 7. Mass spectra from in cabin and external air during flight C040. Note that the AMS was switched from cabin to ambient and back to cabin during a profile in the middle of the flight.