COB Basic Cooling Rate LWFPA MWFPA Time Degrees K 6Hrs to achieve operating temperature

Cycling the Stirling Cooler: FPA Temperature Response Deg. K LWFPA MWFPA ColdFinger Elapsed Time (Minutes) Stirling Off Stirling On Nominal T Max. Operating T Summary: 1.Stirling cooler turned off for one hour 2.Detectors still responsive for 30 mins mins then required to re-attain operational temperature FPA In-Op FPA Re-stabilized

Stirling Off – On Noise Samples Channel 5 All Port 2 LWIR (Ch  m) Stirling “On” Stirling “Off”

60 Hz Stirling Noise Blow-Up Zoom LWIR (Ch  m)

NET (3.7µm to 13.0µm) Degrees Cooler On Cooler Off Old MAS 4.0 µm

NET (13.0µm to 14.5µm) Degrees Cooler On Cooler Off Old MAS µm

NEdT eMAS vs Old MAS Degrees Cooler On Cooler Off Old MAS MAS Flight µm

µm 40C30C 20C / Controller Off 15C / / / / / / / / / / / / / eMAS NEdT (Varying with Target Temp) Extended-Area BB Target Temperature (cooler on)

MAS SWIR Spectrometer MAS VNIR Spectrometer New eMAS-IR Spectrometer installed on optical bench

IR Spectrometer

COB Internal Wiring: Possible source of microphonics?

IR Noise Investigation Issue: 60Hz coupling mechanism: electrical or mechanical? Tests completed: 1.Turn off Stirling: noise disappears 2.Turn off scan motor (digitizer running): noise remains 3.Blank-off COB window (obviates any fore-optic vibration effect) noise remains Tests remaining: 1.Run Stirling from external controller - electrical isolation test 2.Isolate various grounds from digiti9zer to scanhead 3.Shake table test (induce 60Hz vibration with COB cold, Stirling off) 4.Procure active compensator (~12 weeks, plus controller development)

Other Required Tests Investigate NEdT dependency on scene temperature Investigate linearity of radiometric response Temperature chamber test: - View cold EABB plate (linearity test) - Simulate forced air cooling of Stirling Simulate flight operation timeline (~40 min gap in Stirling power) Will attempt to accomplish these before test flights on 8/20 – 8-31

Test Flight Plan (22 ER-2 hours available) Implement engineering data telemetry on ER-2/NASDAT 2-Hour FCF (may extend) 1 or 2 6-hour missions: Lake Tahoe ASTER Buoys Satellite under-passes Open ocean High clouds

Notional Flight Timeline In Lab: Scan head in tail cone, on cart; connected to AC unit on support cart. Tail cone and AC carts wheeled as close to ramp as possible (AC unit on extension cord) Disconnect AC cart from scan head (at hangar door?) Mate tail cone to aircraft (AC now off) Engine start eMAS power on by pilot (no cooling) 0+00 Launch (cooling begins) 0+20 Aircraft at altitude 0+?? LWIR bands operational.

New Motor/Mirror Assembly Port 2 Dewar Location (temporarily removed) SDL IR Spectrometer Housing Port 1 Detector eMAS Scan Head SDL Electronics Package

SDL IR Spectrometer Housing Sterling Cooler SDL Electronics Package eMAS Scan Head Cooling Air Plenum (Ducting Removed)

New Motor/Mirror/Encoder Unit

Interim Digitizer (upgraded MAS unit)

BB ControllerPower Module Cryo Controller LINUX CPU Data SSDs Motor Controller PCB Backplane ESS Module Interim Digitizer (upgraded MAS unit)

Other Issues Can eMAS-IR and eMAS-HSI fit in same pod as CPL? Apparent total pod-weight issue Need exact weight of Brandywine system.