Hi Framer, totally agree it would be good to have an idea of the likely temperature. The following is a simplified formula which may help:
TAT = SAT (1 + [0.2 x M2])
where,
TAT and SAT are expressed in degrees Kelvin (Kelvin = Celsius + 273.15)
M2 = Mach no squared (sorry, couldn't work out superscript on iPad)
0.2 is a simplified factor which includes ratio of specific heats and assumes an empirical recovery factor for the probe of 1.0.
So, 220 KIAS at 10,000 ft in an ISA atmosphere:
SAT = -4.8 degrees Celsius = 268.4 degrees Kelvin
M = 0.4
Using the formula above,
TAT = 277 degrees Kelvin = 4 degrees Celsius
From the MEL, I guess that means the flight deck could be at around 29 degrees Celsius. From what I hear anecdotally, the flight deck does get quite uncomfortable so that could be correct. Hopefully the maths is correct........