May 8, 1998 1st Flight
Crew: Streibel, Miller, Arnott, Poellot
{return}
144437 Takeoff, cirrus mission. Altimeter setting 29.91, no clouds other than high scattered cirrus.
144715 Resetting LiCor zero to 5.00.
145810 Cleared direct to CART. Will start at 28,000'.
150100 Approaching CART, 15 miles out, cirrus appears to be in two layers, one at our altitude and one higher.
150234 The EG&G oscillating some today. The cryo looks good, LiCor a slight offset.
150256 Getting into cirrus particles, 300-600 mm, possible rosettes. Note: we're not at cloud base at 28,000'.
150518 Passing under an old contrail 2 miles north of CART. Turning west ñ winds are 260/107.
150730 Heading upwind, paralleling old contrail we had passed under.
150850 Bullet rosettes up to 800 mm. Descending from 28,000 to 27,000' to see if we can get to base.
151100 Noticed the cryo is venting LN2 will reset.
151250 About 4.5 miles downwind of CART, heading 240.
151400 Lining up on 260 heading inbound, 1.5 miles to go.
151448 CART, 27,000'
151525 Will turn off cryo to reset. In fairly thick cirrus at 27,000'. Actually concentrations are only a few per liter, but particles are fairly large. Seeing a halo.
151655 Turning and climbing to 28,000'.
152100 3.5 miles from CART, heading 260, level 28,000'. Turning cryo back on. Still seeing bullet rosettes in 400-800 mm size range.
152224 CART, 28,000'.
153015 CART, 29,000'. We are blocked by traffic from climbing.
153700 Trying to get cryo working. The EG&G is oscillating again.
153758 CART, 29,000'. Cirrus is thin above.
153950 Particles have gotten smaller, 200 mm or so. Higher concentrations on 2d shadow/or small particles.
154330 In spiral descent.
154520 Cryo hygrometer working again.
155300 The ozone internal pump has stopped.
155405 Descending through 23,500', still in cloud. Particles are 200-500 mm. Good halo. Particles are bullet rosettes. At 23,000' we're not out the bottom of cloud, but airspace is restricted below us. We're going to revert to step climb pattern.
155913 CART, 23,000', heading 260.
…
162600 CART, 27,000'. Wind 256/100. Fairly low concentrations, still have halo.
162910 At 28,000', in very light turbulence.
162930 (approx.) Narrow patch of high particle concentration, coincident with start of EG&G oscillation.
163249 CART, 28,000'
163936 CART, 29,000'. Concentrations about 20/L, fairly small, 100-300 mm, a few larger ones. Getting closer to cloud top.
164617 CART, 30,000'. In cloud, mixture of particle sizes, mostly small. Shadow/or running 40-70/L, mostly around 40-50.
165205 In bound at 31,000', right at cloud top, Tops maybe a little higher over the CART and upwind, than downwind.
165339 CART, .4 miles north. Wind 253/114.
165725 Starting spiral descent from 31,000'.
170125 Adjusted CN airflow higher, which brought the concentrations up a little bit.
170250 Descending through 28,900'. Concentrations a little lower her again. 200-300 mm particles, no halo. Now in the 300-600 mm range, getting a faint halo.
171400 At 25,000', waiting for clearance lower.
171600 Descending.
172003 At 23,000'. Particles 400-700 mm, some larger aggregates. Temperature 23_C.
174258 CART, 23,000'.
174435 End of mission ñ return for fuel.
175500 CR-1 turned off.
175936 Landing
3 hours +15 minutes
3.3 hours