"On August 1 last year,

“On August 1 last year, a Boeing 737-838 (VH-VZR) operated by Qantas performed a “tailstrike” while taking off from Sydney airport. Today, the Australian Transport Safety Bureau (ATSB) has concluded that the strike was caused by the co-pilot fat-fingering the plane’s takeoff weight: instead of typing the plane’s actual weight of 76,400kg into the iPad, he accidentally typed 66,400kg. As a result, the plane didn’t have quite enough thrust to clear the runway without clipping the ground with its tail.”

This is why physical keypads are nice.

And checksums.

@Terris_Linenbach : Interesting suggestion. Might have something with the conservatism inherent in FAA safety rules, and overblown fear of the wheel sensor producing a wrong number.