Friday 9th - Ian's Box Experiment

Another duel purpose flight today as we attempt to map out surface heat fluxes and then sample an air parcel, at three levels, before flying downstream and resampling (hopefully) the same air parcel again. The intracicies of this were again explained to a slightly confused audience by Ian at the morning briefing, before all involved in the flight headed off to the airport.

 
Diagram

The Sea Below

 

Flight manager Alan contraversially failed to cause any delays to takeoff, and we were soon away, again sticking to fairly low levels to prevent the turbulence probe from icing up. The first leg, completing a circuit of the box mapping out the heat fluxes went without a hitch, though after the spectacular flights of late the poor visibility and grey sea were a little disappointing. Having completed the first lap of the box, and back at our starting point, we flew the first leg of the box again at 100ft, 1500ft, and at the top of the boundary layer. The turbulence probe quickly iced up once we reached 1500ft, although by this point turbulence data was less essential. The plane then flew downstream to the opposite side of the box, repeating the profiles just completed. This done, we ascended for a dropsonde leg through the middle of the box, everyone relieved to be able to move about after a substantial amount of time strapped in. All of the dropsondes launched perfectly, and the plane and a satisfied crew returned home with more good data in hand.