AO2:
20100330: 
Opened up AO2 thermistor to check on signal issues.
Found all teflon wires on instrument side to be fine.
Found + and red dot wires (pos and inst gnd?) to be touching 
on thermistor side (stiff wires).  
Moved these two apart, and reconnected sensor.
Turned on O2, Pump and Cyl boxes, and checked reading in AO2 software.
At temps estimated to be roughly 5 degrees C, 
sensor still reads 100C.  
This did NOT fix sensor problem.
May be an extreme calibration issue due to extreme heat cycling, 
or may have harware issue on instrument side.

100331: Day of Flight

20:39:00-20:39:45 BreathTest1.  Conclusion: no visible leak.

21:06 Layer of clouds. O2 and CO2 signals spike, stay noisy
22:35 Forced cal early to get whole upcoming profile of ITCZ from 41K down.
23:20 Noticing that deltaCO2 41Kft-1Kft was ~1 ppm, deltaO2 ~15 per meg.
	Very small gradient for that great an altitude difference
	But expected in highly convective region--ITCZ.

01:50~ Delayed cal a bit to get more of approach to Pago Pago

MED:
System still leaks during overnight leakcheck.
why is the total leakrate the same for the system if MEDPSA issues is solved?
When the system's off, bypass is disengaged, and MEDPSA and Pup are in a connected 
(tho, with pump in between) section of the system.  
That still rises to ambient by the time I turn on MEDUSA in the morning of the flight, 
but the section downstream of the flask has leaked at a much lower rate.   
When you turn the system on, it engages bypass, 
and the system equilibrates with the section of tubing just dnstrm of the pump.

At rest, and open, Pressure Meter values:
PUp: 756
Pdn: 769
Pbyp: 785

Substantial offsets now.  We should have PCs recalibrated for HIPPO4.

21:13 Closed flasks 1-6