[brovonov]

Lower, according to the report

"Two samples from the air induction elbow were subjected to testing, using a heat-flux differential scanning calorimeter, to determine their glass transition temperature. The measured glass transition temperature for the first sample was 52.8°C, and 54.0°C for the second sample"

Yeah, they might have used ABS-CF filament, but unless they got it from a good brand that uses good resin and proper printing parameters, the actual Tg will be lower, plus the stress from the vibration/load could have made the part fail if it was not for the heat later in flight.

[CarVac]

Some manufacturers fudge the Tg.

Polymaker Polylite ABS has a claimed Tg of 101°C but the HDT curve clearly shows it starting to lose strength at 50°C, for example.

[brovonov]

Polymaker's ABS is dubious too because it is blended with PETG. They are coming out with a Pro version that has a higher Tg and requires way higher chamber temps to print properly.

[zuppy]

by the glass transition temperature, i'm willing to bet it was printed with pla (probably pla-cf).