(the NASA Gulfstream V, outfitted with aerogephysical instruments to map the ice sheets. Credit: David Porter, LDEO)
After a few delays, Ryan and I arrive in hot and muggy Houston, finding our crates and large boxes already in the hangar and ready to be unpacked so we can build them up again. A few modifications are needed to be made to the rack after inspection by engineers at NASA, each with their own expertise and eye on a specific aspect of each team’s instrument.
After each of the three teams have integrated their equipment on the Gulfstream V, each team needs to test their equipment under a range of flight conditions. These are designed to be progressively more rigorous, in terms of stresses and possible scenarios. Since this every team has flown with NASA OIB in the past, there are several of these tests that work like clockwork and the boxes can be ticked off quickly. However, being on a new type of aircraft this year (in the past we have used NASA DC-8, P3, and C-130), working with a new NASA Space Center (Johnson this year, Armstrong and Wallops in the past), as well as constant upgrading of each instrument team to extend their capabilities, improve reliabilitity, and reduce uncertaintlies, means that issues always crop up. Flying the “shakedown” flight at home, where we have access to the right parts, tools, and NASA expertise, means that fixes are quicker and better when discovered before we get into the field.
For 2019 Antarctic season, the radar team from University of Kansas CReSIS, needed several high roll maneuvers for side-lobe characterization. These flight conditions are useless, and actually potentially damaging, for the Lamont Gravimeter Suite, so we kept our system off. On the other hand, the laser team ATM needs are similar, so we combined out shakedown segments into a single flight. For gravity, we want a straght and level segment as long as we can (at least 15 km) crossing a geological gradient at 90-degrees to the flight direction.