HU-25C Guardian 09/24/15

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Flight Number: 
OIB2015 Arctic Northwest Coastal A
Payload Configuration: 
ATM & DMS
Nav Data Collected: 
No
Total Flight Time: 
3.7 hours
Flight Segments: 
From:BGTLTo:BGTL
Start:09/24/15 13:03 Z Finish:09/24/15 16:48 Z
Flight Time:3.7 hours
Log Number:15F005PI:John Woods
Funding Source:Thomas Wagner - NASA - SMD - ESD Cryosphere & International Polar Year
Purpose of Flight:Science
Comments:The HU-25 Falcon completed its second data flight for OIB Arctic out of Thule today. Next flight is scheduled for Friday, September 25.
Flight Hour Summary: 
15F00516F002
Flight Hours Approved in SOFRS100
Flight Hours Previously Approved 67.4
Total Used32.665.3
Total Remaining 2.1
16F002 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining Miles Flown
10/05/15OIB2015 Arctic Sea Ice CentralScience3.63.663.8
10/05/15OIB2015 Arctic Sea Ice EastScience3.87.460
10/06/15OIB2015 Arctic Ice-Sat2 NorthScience411.456
10/07/15OIB2015 Arctic Transit Thule to KangerlussuaqTransit213.454
10/08/15OIB2015 Arctic Southwest Coastal AScience3.817.250.2
10/08/15OIB2015 Arctic Thomas-Jakobshavn 01Science3.720.946.5
10/09/15OIB2015 Arctic Umanaq BScience3.924.842.6
10/13/15OIB2015 Arctic Jakobshavn Eqip StoreScience2.927.739.7
10/13/15OIB2015 Arctic Southeast Coastal AScience3.631.336.1
10/18/15OIB2015 Arctic Southeast Coastal BScience4.135.432
10/19/15OIB2015 Arctic Helheim-KangerdlugussuaqScience3.739.128.3
10/19/15OIB2015 Arctic Helheim-Kangerdlugussuaq Gap BScience3.94324.4
10/20/15OIB2015 Arctic Jakobshavn Mop-UpScience3.746.720.7
10/20/15OIB2015 Arctic Southwest Coastal BScience3.750.417
10/21/15OIB2015 Arctic Southwest Coastal CScience3.453.813.6
10/21/15OIB2015 Arctic K-EGIG-SummitScience3.757.59.9
10/22/15OIB2015 Arctic Mopup SouthScience259.57.9
10/22/15OIB2015 Arctic Ferry BGSF-CYYRFerry2.261.75.7
10/23/15OIB2015 Arctic Ferry CYYR-KRICFerry3.3652.4
10/23/15OIB2015 Arctic Ferry CYYR-KRICFerry0.365.32.1
15F005 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining Miles Flown
09/15/15OIB #1Check2.72.797.3
09/20/15OIB #2, 3, 4Ferry2.75.494.6
09/21/15OIB #2, 3, 4Ferry2.37.792.3
09/21/15OIB #2, 3, 4Ferry29.790.3
09/23/15OIB2015 Arctic North Central Gap 02Science3.913.686.4
09/24/15OIB2015 Arctic Northwest Coastal AScience3.717.382.7
09/25/15OIB2015 Arctic Northwest Coastal BScience3.821.178.9
09/28/15OIB2015 Arctic Sea Ice WestScience3.724.875.2
09/30/15OIB2015 Arctic North Central Gap 01Science3.928.771.3
09/30/15OIB2015 Arctic Zachariae-79NScience3.932.667.4

Flight Reports began being entered into this system as of 2012 flights. If there were flights flown under an earlier log number the flight reports are not available online.

Related Science Report: 

OIB - HU-25C Guardian 09/24/15 Science Report

Mission: 
OIB
Mission Summary: 

Mission: Northwest Coastal A (priority: high)

This mission is similar to the Northwest Coastal A mission flown in Spring 2015, but with the uppermost lines shortened to accommodate the shorter range of the Falcon aircraft. These shortened lines are completed by the companion “Falcon Northwest Coastal B” mission.

Weather today was ideal for this mission, with easterly (and thus downsloping and hence drying) flow at Thule and along the upper Baffin Bay coast for several hundred miles to the south.  Skies were almost perfectly clear for the entire flight.  The Lincoln Sea and the entire northern coastal area of Greenland were covered in cloud and fog, and northeastern Greenland was influenced by an offshore low pressure system which covered our science targets in that area with high-level cirrus clouds.

We encountered several problems with the ATM instrument system this morning, including related hardware issues with the precise navigation system and an intermittent power issue with the ATM laser controller.  We were able to resolve all of these issues, but this caused a two-hour delay in our takeoff.  After takeoff we encountered an entirely separate issue, namely a "dirty" start pulse for the ATM laser.  This issue was resolved within 40 minutes of takeoff, altough we are not certain whether we resolved it with electronic adjustments, or whether it resolved itself.  Our theories to explain the issue include a partially fouled nadir window, a very thin cirrus cloud layer just below the aircraft, or perhaps haze, any of which could explain the dirty start pulse under certain conditions.  Our internal discussions will continue.  A dirty start pulse can adversely affect the accuracy of ATM range measurements and hence topographic measurements, but as of this writing we do not know to what degree the early-mission data may be affected.  Data collected after the first 40 minutes was clean.

Despite this early-mission problem, we are developing increasing confidence in higher altitude operations for ATM.  We began the flight at 25,000' MSL, climbing to 30,000' and then 35,000' later in the flight.  

DMS and the FLIR camera performed well all day.

We conducted a ramp pass at 15,000' AGL.

Data volumes:
DMS: 23.3 Gb
Narrow Swath ATM: 18 Gb
FLIR: 1.8 Gb

total data collection time: 3.5 hrs

Images: